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1.
Inorg Chem ; 63(6): 3063-3074, 2024 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-38285631

RESUMO

Phenanthroline diamide ligands have been widely used in the separation of trivalent actinides and lanthanides, but little research has focused on extractants with asymmetrical substitutes. Two novel asymmetrical phenanthroline-based ligands N2,N2,N9-triethyl-N9-tolyl-1,10-phenanthroline-2,9-dicarboxamide (DE-ET-DAPhen) and N2-ethyl-N9,N9-dioctyl-N2-tolyl-1,10-phenanthroline-2,9-dicarboxamide (DO-ET-DAPhen) were first synthesized in this work, whose extraction ability and complexation mechanism to trivalent actinides [An(III)] and lanthanides [Ln(III)] were systematically investigated. The ligands dissolved in n-octanol exhibit good extraction ability and high selectivity toward Am(III) in acidic solutions. The complexation mechanism of the ligands with Ln(III) in solution and solid state was analyzed using slope analysis, 1H NMR spectrometric titration, ESI-MS, and calorimetric titration. It is revealed that the ligands complex with Am(III)/Eu(III) with 1:1 stoichiometry. The stability constant (log ß) of the complexation reaction of Eu(III) with DE-ET-DAPhen determined by UV-vis spectrophotometric and calorimetric titration is higher than that of DO-ET-DAPhen, indicating the stronger complexation ability of DE-ET-DAPhen. Meanwhile, the calorimetric titration results show that the complexation process is exothermic with a decreased entropy. The structures of 1:1 complexes of Eu(III) and Nd(III) with DE-ET-DAPhen were analyzed through single-crystal X-ray diffraction. This work proves that ligands containing asymmetrical functional groups are promising for An(III)/Ln(III) separation, which shows great significance in efficient extractants designed for the spent nuclear fuel reprocessing process.

2.
Inorg Chem ; 63(23): 10511-10518, 2024 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-38768636

RESUMO

Selective actinide coordination (from lanthanides) is critical for both nuclear waste management and sustainable development of nuclear power. Hydrophilic ligands used as masking agents to withhold actinides in the aqueous phase are currently highly pursued, while synthetic accessibility, water solubility, acid resistance, and extraction capability are the remaining problems. Most reported hydrophilic ligands are only effective at low acidity. We recently proved that the phenanthroline diimide skeleton was an efficient building block for the construction of highly efficient acid-resistant hydrophilic lanthanide/actinide separation agents, while the limited water solubility hindered the loading capability of the ligand. Herein, amine was introduced as the terminal solubilizing group onto the phenanthroline diimide backbone, which after protonation in acid showed high water solubility. The positively charged terminal amines enhanced the ligand water solubility to a large extent, which, on the other side, was believed to be detrimental for the coordination and complexation of the metal cations. We showed that by delicately adjusting the alkyl chain spacing, this intuitive disadvantage could be relieved and superior extraction performances could be achieved. This work holds significance for both hydrophilic lanthanide/actinide separation ligand design and, concurrently, offers insights into the development of water-soluble lanthanide/actinide complexes for biomedical and bioimaging applications.

3.
Bioorg Chem ; 144: 107110, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38224636

RESUMO

Wet age-related macular degeneration (w-AMD) is one of the leading causes of vision loss in industrialized countries. A large body of evidence suggests that inhibitors targeting VEGFR2 may be effective in the treatment of w-AMD. The identification of an oral VEGFR2 inhibitor for the treatment of w-AMD provides an opportunity for a route of administration other than intravitreal injection. While screening potent VEGFR2 inhibitors at the enzyme and cellular levels, ensuring the safety of the compounds was our primary strategy for screening optimal compounds. Finally, compound 16 was identified, exhibiting enhanced inhibition of VEGFR2 enzyme and proliferation of BaF3-TEL-VEGFR2 cells compared to Vorolanib. Compound 16 had a weak inhibitory effect on human Ether-a-go-go-related gene (hERG) channel currents, showing a cardiac safety profile similar to Vorolanib. Compound 16 showed no significant toxicity to human liver cell LX-2, indicating a liver safety profile similar to Vorolanib. The water solubility of compound 16 was found to be higher than that of Vorolanib when tested at pH = 7.4. In addition, compound 16 was found to inhibit VEGFR2 phosphorylation in human umbilical vein endothelial cells (HUVECs) in a dose-dependent manner by WB assay. Furthermore, the in vitro preliminary evaluation of the drug-like properties of compound 16 showed remarkable plasma stability and moderate liver microsomal stability. Based on in vivo pharmacokinetic studies in ICR mice, compound 16 exhibited acceptable oral bioavailability (F = 20.2 %). Overall, these findings provide evidence that compound 16 is a leading potential oral drug candidate for w-AMD.


Assuntos
Degeneração Macular , Camundongos , Animais , Humanos , Camundongos Endogâmicos ICR , Células Endoteliais da Veia Umbilical Humana , Degeneração Macular/tratamento farmacológico , Inibidores da Angiogênese/farmacologia , Receptor 2 de Fatores de Crescimento do Endotélio Vascular
4.
Bioorg Chem ; 143: 107010, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38056387

RESUMO

Alzheimer's disease (AD) is a neurodegenerative disorder characterized by progressive memory loss and deficits in cognitive domains. Low choline levels, oxidative stress, and neuroinflammation are the primary mechanisms implicated in AD progression. Simultaneous inhibition of acetylcholinesterase (AChE) and reactive oxygen species (ROS) production by a single molecule may provide a new breath of hope for AD treatment. Here, we describe donepezil-tacrine hybrids as inhibitors of AChE and ROS. Four series of derivatives with a ß-amino alcohol linker were designed and synthesized. In this study, the target compounds were evaluated for their ability to inhibit AChE and butyrylcholinesterase (BuChE) in vitro, using tacrine (hAChE, IC50 = 305.78 nM; hBuChE, IC50 = 56.72 nM) and donepezil (hAChE, IC50 = 89.32 nM; hBuChE, IC50 = 9137.16 nM) as positive controls. Compound B19 exhibited an excellent and balanced inhibitory potency against AChE (IC50 = 30.68 nM) and BuChE (IC50 = 124.57 nM). The cytotoxicity assays demonstrated that the PC12 cell viability rates of compound B19 (84.37 %) were close to that of tacrine (87.73 %) and donepezil (79.71 %). Potential therapeutic effects in AD were evaluated using the neuroprotective effect of compounds against H2O2-induced toxicity, and compound B19 (68.77 %) exhibited substantially neuroprotective activity at the concentration of 25 µM, compared with the model group (30.34 %). Furthermore, compound B19 protected PC12 cells from H2O2-induced apoptosis and ROS production. These properties of compound B19 suggested that it was a multi-functional agent with AChE inhibition, anti-oxidative, anti-inflammatory activities, and low toxicity and that it deserves further investigation as a promising agent for AD treatment.


Assuntos
Doença de Alzheimer , Fármacos Neuroprotetores , Animais , Ratos , Tacrina/farmacologia , Tacrina/uso terapêutico , Donepezila/uso terapêutico , Doença de Alzheimer/tratamento farmacológico , Butirilcolinesterase/metabolismo , Inibidores da Colinesterase , Acetilcolinesterase/metabolismo , Peróxido de Hidrogênio , Espécies Reativas de Oxigênio , Simulação de Acoplamento Molecular , Relação Estrutura-Atividade
5.
Bioorg Chem ; 150: 107514, 2024 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-38870704

RESUMO

Alzheimer's disease (AD), a progressive neurodegenerative disorder, has garnered increased attention due to its substantial economic burden and the escalating global aging phenomenon. Amyloid-ß deposition is a key pathogenic marker observed in the brains of Alzheimer's sufferers. Based on real-time, safe, low-cost, and commonly used, near-infrared fluorescence (NIRF) imaging technology have become an essential technique for the detection of AD in recent years. In this work, NIRF probes with hemicyanine structure were designed, synthesized and evaluated for imaging Aß aggregates in the brain. We use the hemicyanine structure as the parent nucleus to enhance the probe's optical properties. The introduction of PEG chain is to improve the probe's brain dynamice properties, and the alkyl chain on the N atom is to enhance the fluorescence intensity of the probe after binding to the Aß aggregates as much as possible. Among these probes, Z2, Z3, Z6, X3, X6 and T1 showed excellent optical properties and high affinity to Aß aggregates (Kd = 24.31 âˆ¼ 59.60 nM). In vitro brain section staining and in vivo NIRF imaging demonstrated that X6 exhibited superior discrimination between Tg mice and WT mice, and X6 has the best brain clearance rate. As a result, X6 was identified as the optimal probe. Furthermore, the docking theory calculation results aided in describing X6's binding behavior with Aß aggregates. As a high-affinity, high-selectivity, safe and effective probe of targeting Aß aggregates, X6 is a promising NIRF probe for in vivo detection of Aß aggregates in the AD brain.

6.
Ecotoxicol Environ Saf ; 278: 116404, 2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38705038

RESUMO

Manganese (Mn) is an essential trace element for maintaining bodily functions. Excessive exposure to Mn can pose serious health risks to humans and animals, particularly to the nervous system. While Mn has been implicated as a neurotoxin, the exact mechanism of its toxicity remains unclear. Ferroptosis is a form of programmed cell death that results from iron-dependent lipid peroxidation. It plays a role in various physiological and pathological cellular processes and may be closely related to Mn-induced neurotoxicity. However, the mechanism of ferroptosis in Mn-induced neurotoxicity has not been thoroughly investigated. Therefore, this study aims to investigate the role and mechanism of ferroptosis in Mn-induced neurotoxicity. Using bioinformatics, we identified significant changes in genes associated with ferroptosis in Mn-exposed animal and cellular models. We then evaluated the role of ferroptosis in Mn-induced neurotoxicity at both the animal and cellular levels. Our findings suggest that Mn exposure causes weight loss and nervous system damage in mice. In vitro and in vivo experiments have shown that exposure to Mn increases malondialdehyde, reactive oxygen species, and ferrous iron, while decreasing glutathione and adenosine triphosphate. These findings suggest that Mn exposure leads to a significant increase in lipid peroxidation and disrupts iron metabolism, resulting in oxidative stress injury and ferroptosis. Furthermore, we assessed the expression levels of proteins and mRNAs related to ferroptosis, confirming its significant involvement in Mn-induced neurotoxicity.


Assuntos
Ferroptose , Sobrecarga de Ferro , Peroxidação de Lipídeos , Manganês , Oxirredução , Ferroptose/efeitos dos fármacos , Animais , Manganês/toxicidade , Camundongos , Peroxidação de Lipídeos/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Síndromes Neurotóxicas/patologia , Masculino , Ferro/toxicidade , Ferro/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Humanos
7.
Ann Rheum Dis ; 82(11): 1444-1454, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37567607

RESUMO

OBJECTIVES: Reactivation of anergic autoreactive B cells (BND cells) is a key aetiological process in systemic lupus erythematosus (SLE), yet the underlying mechanism remains largely elusive. This study aimed to investigate how BND cells participate in the pathogenesis of SLE and the underlying mechanism. METHODS: A combination of phenotypical, large-scale transcriptome and B cell receptor (BCR) repertoire profiling were employed at molecular and single cell level on samples from healthy donors and patients with SLE. Isolated naïve B cells from human periphery blood were treated with anti-CD79b mAb in vitro to induce anergy. IgM internalisation was tracked by confocal microscopy and was qualified by flow cytometer. RESULTS: We characterised the decrease and disruption of BND cells in SLE patients and demonstrated IL-4 as an important cytokine to drive such pathological changes. We then elucidated that IL-4 reversed B cell anergy by promoting BCR recycling to the cell surface via STAT6 signalling. CONCLUSIONS: We demonstrated the significance of IL-4 in reversing B cell anergy and established the scientific rationale to treat SLE via blocking IL-4 signalling, also providing diagnostic and prognostic biomarkers to identify patients who are most likely going to benefit from such treatments.

8.
Bioorg Chem ; 134: 106441, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36854233

RESUMO

A novel series of N-methyl-propargylamine derivates were designed, synthesized, and evaluated as isoform-selective monoamine oxidases (MAO) inhibitors for the treatment of nervous system diseases. The in vitro studies showed some of the compounds exhibited considerable MAO-A selective inhibitory activity (IC50 of 14.86-17.16 nM), while some of the others exhibited great MAO-B selective inhibitory activity (IC50 of 4.37-17.00 nM). Further studies revealed that compounds A2 (IC50 against MAO-A: 17.16 ± 1.17 nM) and A5 (IC50 against MAO-B: 17.00 ± 1.10 nM) had significant abilities to protect PC12 cells from H2O2-induced apoptosis and reactive oxygen species (ROS) production. The parallel artificial membrane permeability assay showed A2 and A5 would be potent to cross the blood-brain barrier. The results indicated that A2 showed potential use in the therapy of MAO-A related diseases, such as depression and anxiety; while A5 exhibited promising ability in the treatment of MAO-B related diseases, such as Alzheimer's disease and Parkinson's disease.


Assuntos
Doença de Alzheimer , Peróxido de Hidrogênio , Ratos , Animais , Relação Estrutura-Atividade , Inibidores da Monoaminoxidase/farmacologia , Monoaminoxidase/metabolismo
9.
J Enzyme Inhib Med Chem ; 38(1): 2192439, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36950955

RESUMO

A series of OA-tacrine hybrids with the alkylamine linker was designed, synthesized, and evaluated as effective cholinesterase inhibitors for the treatment of Alzheimer's disease (AD). Biological activity results demonstrated that some hybrids possessed significant inhibitory activities against acetylcholinesterase (AChE). Among them, compounds B4 (hAChE, IC50 = 14.37 ± 1.89 nM; SI > 695.89) and D4 (hAChE, IC50 = 0.18 ± 0.01 nM; SI = 3374.44) showed excellent inhibitory activities and selectivity for AChE as well as low nerve cell toxicity. Furthermore, compounds B4 and D4 exhibited lower hepatotoxicity than tacrine in cell viability, apoptosis, and intracellular ROS production for HepG2 cells. These properties of compounds B4 and D4 suggest that they deserve further investigation as promising agents for the prospective treatment of AD.


Assuntos
Doença de Alzheimer , Doença Hepática Induzida por Substâncias e Drogas , Humanos , Tacrina/farmacologia , Inibidores da Colinesterase/farmacologia , Doença de Alzheimer/tratamento farmacológico , Acetilcolinesterase/metabolismo , Relação Estrutura-Atividade
10.
Immun Ageing ; 19(1): 50, 2022 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-36320075

RESUMO

BACKGROUND: Patients with systemic lupus erythematosus (SLE) are highly susceptible to infection and cardiovascular events, suggesting that chronic antigenic stimulation may accelerate premature aging in SLE patients. Premature aging in SLE is often accompanied with the expansion of cytotoxic CD4 + CD28-T cells. Damage caused by CD4 + CD28- T cells enhances the progressive aging of the tissue function and loss of organism's fitness. The high serum level of IL-15 has been implicated in the pathogenesis of SLE, but its role in CD4 + CD28-T cell-mediated cytotoxicity in nephritic SLE remains unclear. The aim of this study was to investigate the effect of IL-15 on functional properties and associated renal damage of cytotoxic CD4 + CD28- T cell in lupus nephritis (LN). RESULTS: Flow cytometry showed that the number of circulating innate-like CD4 + CD28- T cells was increased in patients with nephritic SLE. Immunofluorescence showed CD4 + CD28- T cell infiltration in the kidney of LN patients, which was correlated with multiple clinicopathological features including estimated glomerular filtration rate (eGFR), proteinuria, the proportion of glomerulosclerosis and the degree of renal chronicity. In addition, a high level of IL-15 and IL15-expressing macrophage infiltration was detected in the periglomerular and intraglomerular tissues of LN patients, which enhanced the innate features, cytokine secretion and migratory capability of CD4 + CD28- T cells, and finally exerted direct TCR-independent cytotoxicity on glomerular endothelial cells in an IL-15-dependent manner in vitro. CONCLUSION: Our study demonstrated that excessive IL-15 potentially promoted cytotoxic CD4 + CD28- T cell-mediated renal damage in LN. This finding may provide new insights into the potential association of premature aging and tissue damage in LN.

11.
Proc Natl Acad Sci U S A ; 116(37): 18550-18560, 2019 09 10.
Artigo em Inglês | MEDLINE | ID: mdl-31451659

RESUMO

Excessive self-reactive and inadequate affinity-matured antigen-specific antibody responses have been reported to coexist in lupus, with elusive cellular and molecular mechanisms. Here, we report that the antigen-specific germinal center (GC) response-a process critical for antibody affinity maturation-is compromised in murine lupus models. Importantly, this defect can be triggered by excessive autoimmunity-relevant CD11c+Tbet+ age-associated B cells (ABCs). In B cell-intrinsic Ship-deficient (ShipΔB) lupus mice, excessive CD11c+Tbet+ ABCs induce deregulated follicular T-helper (TFH) cell differentiation through their potent antigen-presenting function and consequently compromise affinity-based GC selection. Excessive CD11c+Tbet+ ABCs and deregulated TFH cell are also present in other lupus models and patients. Further, over-activated Toll-like receptor signaling in Ship-deficient B cells is critical for CD11c+Tbet+ ABC differentiation, and blocking CD11c+Tbet+ ABC differentiation in ShipΔB mice by ablating MyD88 normalizes TFH cell differentiation and rescues antigen-specific GC responses, as well as prevents autoantibody production. Our study suggests that excessive CD11c+Tbet+ ABCs not only contribute significantly to autoantibody production but also compromise antigen-specific GC B-cell responses and antibody-affinity maturation, providing a cellular link between the coexisting autoantibodies and inadequate affinity-matured antigen-specific antibodies in lupus models and a potential target for treating lupus.


Assuntos
Subpopulações de Linfócitos B/imunologia , Linfócitos B/imunologia , Centro Germinativo/imunologia , Lúpus Eritematoso Sistêmico/imunologia , Linfócitos T Auxiliares-Indutores/imunologia , Adulto , Animais , Autoimunidade/imunologia , Subpopulações de Linfócitos B/metabolismo , Linfócitos B/metabolismo , Antígenos CD11/metabolismo , Estudos de Casos e Controles , Diferenciação Celular/imunologia , Modelos Animais de Doenças , Feminino , Humanos , Lúpus Eritematoso Sistêmico/genética , Linfonodos/citologia , Linfonodos/imunologia , Masculino , Camundongos , Camundongos Knockout , Pessoa de Meia-Idade , Fator 88 de Diferenciação Mieloide/genética , Fator 88 de Diferenciação Mieloide/imunologia , Fosfatidilinositol-3,4,5-Trifosfato 5-Fosfatases/genética , Transdução de Sinais/imunologia , Proteínas com Domínio T/metabolismo
12.
J Immunol ; 192(9): 4069-73, 2014 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-24670801

RESUMO

To prevent autoimmunity, anergy of autoreactive B cells needs to be maintained, together with the suppression of hyperactive B cells. We previously reported that CD4(+)CD25(+)Foxp3(+) regulatory T cells (Tregs) can directly suppress autoantibody-producing autoreactive B cells in systemic lupus erythematosus. In this article, we show that Tregs can also reduce the production of autoantibodies in (NZB × NZW)F1 mouse lupus B cells by promoting B cell anergy, both in vitro and in vivo. This phenomenon associated with a reduction in Ca(2+) flux in B cells, and CTLA-4 blockade inhibited the effects of Tregs on anergic lupus B cells. These findings identify a new mechanism by which Tregs can control production of autoantibodies in lupus B cells and, more generally, B cell activity in physiopathological conditions.


Assuntos
Autoimunidade/imunologia , Linfócitos B/imunologia , Anergia Clonal/imunologia , Lúpus Eritematoso Sistêmico/imunologia , Linfócitos T Reguladores/imunologia , Animais , Formação de Anticorpos/imunologia , Autoanticorpos/imunologia , Separação Celular , Ensaio de Imunoadsorção Enzimática , Feminino , Citometria de Fluxo , Camundongos , Camundongos Endogâmicos BALB C
13.
J Immunol ; 190(7): 3054-8, 2013 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-23447682

RESUMO

Th17 CD4(+) cells promote inflammation and autoimmunity. In this study, we report that Th17 cell frequency is reduced in ob/ob mice (that are genetically deficient in the adipokine leptin) and that the administration of leptin to ob/ob mice restored Th17 cell numbers to values comparable to those found in wild-type animals. Leptin promoted Th17 responses in normal human CD4(+) T cells and in mice, both in vitro and in vivo, by inducing RORγt transcription. Leptin also increased Th17 responses in (NZB × NZW)F1 lupus-prone mice, whereas its neutralization in those autoimmune-prone mice inhibited Th17 responses. Because Th17 cells play an important role in the development and maintenance of inflammation and autoimmunity, these findings envision the possibility to modulate abnormal Th17 responses via leptin manipulation, and they reiterate the link between metabolism/nutrition and susceptibility to autoimmunity.


Assuntos
Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD4-Positivos/metabolismo , Leptina/genética , Lúpus Eritematoso Sistêmico/genética , Lúpus Eritematoso Sistêmico/imunologia , Membro 3 do Grupo F da Subfamília 1 de Receptores Nucleares/genética , Células Th17/imunologia , Animais , Modelos Animais de Doenças , Regulação da Expressão Gênica , Humanos , Leptina/metabolismo , Camundongos , Camundongos Knockout , Receptores para Leptina/genética , Receptores para Leptina/metabolismo , Células Th17/metabolismo , Transcrição Gênica
14.
J Immunol ; 188(5): 2070-3, 2012 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-22291185

RESUMO

Fasting is beneficial in the prevention and amelioration of the clinical manifestations of autoimmune diseases including systemic lupus erythematosus. The mechanisms responsible for these effects are not well understood. During fasting, there is a dramatic reduction of the levels of circulating leptin, an adipokine with proinflammatory effects. Leptin also inhibits CD4(+)CD25(+)Foxp3(+) regulatory T cells, which are known to contribute significantly to the mechanisms of peripheral immune tolerance. In this study, we show that fasting-induced hypoleptinemia in (NZB × NZW)F(1) lupus-prone mice induced an expansion of functional regulatory T cells that was reversed by leptin replacement. The specificity of the findings was indicated by the lack of these effects in leptin-deficient ob/ob mice and leptin receptor-deficient db/db mice. These observations help to explain the beneficial effects of fasting in autoimmunity and could be exploited for leptin-based immune intervention in systemic lupus erythematosus.


Assuntos
Diferenciação Celular/imunologia , Jejum , Leptina/sangue , Leptina/deficiência , Lúpus Eritematoso Sistêmico/imunologia , Lúpus Eritematoso Sistêmico/metabolismo , Linfócitos T Reguladores/imunologia , Linfócitos T Reguladores/patologia , Animais , Diferenciação Celular/genética , Feminino , Predisposição Genética para Doença , Leptina/fisiologia , Lúpus Eritematoso Sistêmico/patologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos NZB , Camundongos Obesos , Receptores para Leptina/deficiência , Inanição , Linfócitos T Reguladores/metabolismo
15.
Toxicology ; 502: 153727, 2024 02.
Artigo em Inglês | MEDLINE | ID: mdl-38216111

RESUMO

Manganese is an essential trace element, but overexposure can cause neurotoxicity and subsequent neurodegenerative diseases. Ferroptosis is a form of cell death characterized by lipid peroxidation and iron overload inside cells, which is closely related to manganese neurotoxicity. Manganese can induce ferroptosis through multiple pathways: causing oxidative stress and increased cellular reactive oxygen species (ROS), resulting in lipid peroxidation; depleting glutathione (GSH) and weakening the antioxidant capacity of cells; disrupting iron metabolism and increasing iron-dependent lipid peroxidation; damaging mitochondrial function and disrupting the electron transport chain, leading to increased ROS production. Oxidative stress, iron metabolism disorders, lipid peroxidation, GSH depletion, and mitochondrial dysfunction, typical features of ferroptosis, have been observed in animal and cell models after manganese exposure. In summary, manganese can participate in the pathogenesis of neurodegenerative diseases by inducing events related to ferroptosis. This provides new insights into studying the mechanism of manganese neurotoxicity and developing therapeutic drugs.


Assuntos
Ferroptose , Doenças Neurodegenerativas , Animais , Espécies Reativas de Oxigênio/metabolismo , Manganês/toxicidade , Estudos Retrospectivos , Ferro/toxicidade , Ferro/metabolismo , Peroxidação de Lipídeos , Glutationa/metabolismo , Doenças Neurodegenerativas/induzido quimicamente
16.
Eur J Med Chem ; 265: 116071, 2024 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-38157596

RESUMO

In this study, a series of carbamate derivatives incorporating multifunctional carrier scaffolds were designed, synthesized, and evaluated as potential therapeutic agents for Alzheimer's disease (AD). We used tacrine to modify the aliphatic substituent, and employed rivastigmine, indole and sibiriline fragments as carrier scaffolds. The majority of compounds exhibited good inhibitory activity for cholinesterase. Notably, compound C7 with sibiriline fragment exhibited potent inhibitory activities against human acetylcholinesterase (hAChE, IC50 = 30.35 ± 2.07 nM) and human butyrylcholinesterase (hBuChE, IC50 = 48.03 ± 6.41 nM) with minimal neurotoxicity. Further investigations have demonstrated that C7 exhibited a remarkable capacity to safeguard PC12 cells against H2O2-induced apoptosis and effectively suppressed the production of reactive oxygen species (ROS). Moreover, in an inflammation model of BV2 cells induced by lipopolysaccharide (LPS), C7 effectively attenuated the levels of pro-inflammatory cytokines. After 12 h of dialysis, C7 continued to exhibit an inhibitory effect on cholinesterase activity. An acute toxicity test in vivo demonstrated that C7 exhibited a superior safety profile and no hepatotoxicity compared to the parent nucleus tacrine. In the scopolamine-induced AD mouse model, C7 (20 mg/kg) significantly reduced cholinesterase activity in the brain of the mice. C7 was tested in a pharmacological AD mouse model induced by Aß1-42 and attenuated memory deficits at doses as low as 5 mg/kg. The pseudo-irreversible cholinesterase inhibitory properties and multifunctional therapeutic attributes of C7 render it a promising candidate for further investigation in the treatment of AD.


Assuntos
Doença de Alzheimer , Inibidores da Colinesterase , Ratos , Camundongos , Humanos , Animais , Doença de Alzheimer/tratamento farmacológico , Doença de Alzheimer/induzido quimicamente , Butirilcolinesterase/metabolismo , Tacrina/farmacologia , Tacrina/uso terapêutico , Acetilcolinesterase/metabolismo , Carbamatos/farmacologia , Peróxido de Hidrogênio/farmacologia , Peptídeos beta-Amiloides , Barreira Hematoencefálica/metabolismo , Desenho de Fármacos , Relação Estrutura-Atividade
17.
Int Immunopharmacol ; 118: 109946, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36931174

RESUMO

Systemic lupus erythematosus (SLE) is a chronic multi-organ autoimmune disease characterized by clinical heterogeneity, unpredictable progression, and flare ups. Due to the heterogeneous nature of lupus, it has been challenging to identify sensitive and specific biomarkers for its diagnosis and monitoring. Despite the fact that the mechanism of SLE remains unknown, impressive progress has been made over the last decade towards understanding how different immune cells contribute to its pathogenesis. Research suggests that cellular metabolic programs could affect the immune response by regulating the activation, proliferation, and differentiation of innate and adaptive immune cells. Many studies have shown that the dysregulation of the immune system is associated with changes to metabolite profiles. The study of metabolite profiling may provide a means for mechanism exploration and novel biomarker discovery for disease diagnostic, classification, and monitoring. Here we review the latest advancements in understanding the role of immunometabolism in SLE, as well as the systemic metabolite profiling of this disease along with possible clinical application.


Assuntos
Lúpus Eritematoso Sistêmico , Humanos , Biomarcadores/metabolismo , Diferenciação Celular
18.
ACS Cent Sci ; 9(8): 1642-1649, 2023 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-37637748

RESUMO

Highly selective hydrophilic ligands were believed to be an efficient way to overcome the massive amount of hazardous organic solvent used in the liquid-liquid extraction process and stood as a new frontier in the Lns(III)/Ans(III) partition. Current reported hydrophilic ligands suffer from harsh preparation conditions, inferior extraction performances, limited available chemical structures, and inability to carry out extraction under high acidity. In this article, we report a simple yet efficient carboxylic group modified phenanthroline-diimide ligand which displayed unexpected Lns(III)/Ans(III) and Ans(III)/Ans(III) separation capabilities in 1.5 M HNO3. Unique dimeric architectures for Eu(III) complexes were observed, which could be the origin of the outperforming selectivity and acid resistance. We believe this crystal engineering approach could inspire a renaissance in searching for new functional groups and coordination modes for efficient, high-acid-tolerance Lns(III)/Ans(III) separation ligands.

19.
Arthritis Res Ther ; 25(1): 28, 2023 02 21.
Artigo em Inglês | MEDLINE | ID: mdl-36803548

RESUMO

BACKGROUND: Ectopic ossification is an important cause of disability in patients with ankylosing spondylitis (AS). Whether fibroblasts can transdifferentiate into osteoblasts and contribute to ossification remains unknown. This study aims to investigate the role of stem cell transcription factors (POU5F1, SOX2, KLF4, MYC, etc.) of fibroblasts in ectopic ossification in patients with AS. METHODS: Primary fibroblasts were isolated from the ligaments of patients with AS or osteoarthritis (OA). In an in vitro study, primary fibroblasts were cultured in osteogenic differentiation medium (ODM) to induce ossification. The level of mineralization was assessed by mineralization assay. The mRNA and protein levels of stem cell transcription factors were measured by real-time quantitative PCR (q-PCR) and western blotting. MYC was knocked down by infecting primary fibroblasts with lentivirus. The interactions between stem cell transcription factors and osteogenic genes were analysed by chromatin immunoprecipitation (ChIP). Recombinant human cytokines were added to the osteogenic model in vitro to evaluate their role in ossification. RESULTS: We found that MYC was elevated significantly in the process of inducing primary fibroblasts to differentiate into osteoblasts. In addition, the level of MYC was remarkably higher in AS ligaments than in OA ligaments. When MYC was knocked down, the expression of the osteogenic genes alkaline phosphatase (ALP) and bone morphogenic protein 2 (BMP2) was decreased, and the level of mineralization was reduced significantly. In addition, the ALP and BMP2 were confirmed to be the direct target genes of MYC. Furthermore, interferon-γ (IFN-γ), which showed high expression in AS ligaments, was found to promote the expression of MYC in fibroblasts in the process of ossification in vitro. CONCLUSIONS: This study demonstrates the role of MYC in ectopic ossification. MYC may act as the critical bridge that links inflammation with ossification in AS, thus providing new insights into the molecular mechanisms of ectopic ossification in AS.


Assuntos
Ossificação Heterotópica , Osteoartrite , Proteínas Proto-Oncogênicas c-myc , Espondilite Anquilosante , Humanos , Fosfatase Alcalina/metabolismo , Proteína Morfogenética Óssea 2/metabolismo , Diferenciação Celular/genética , Células Cultivadas , Fibroblastos/metabolismo , Ossificação Heterotópica/metabolismo , Osteoartrite/genética , Osteoartrite/metabolismo , Osteogênese/genética , Espondilite Anquilosante/genética , Espondilite Anquilosante/metabolismo , Fatores de Transcrição/metabolismo , Proteínas Proto-Oncogênicas c-myc/genética , Proteínas Proto-Oncogênicas c-myc/metabolismo
20.
Food Sci Nutr ; 11(7): 4073-4083, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37457189

RESUMO

To overcome problems of browning and crusting during the pretreatment process and provide theoretical guidance for cantaloupe convection drying at 80°C, the effects of blanching (BL) and ultrasonic (US) treatments were examined. The effects of various BL (5, 10, and 15 s) and US (10, 20, 30, and 40 min) durations on convection drying were tested. The moisture ratio, drying rate, moisture effective diffusivity, color, browning, nuclear magnetic resonance characteristics, and texture were assessed. Compared with the control group, the maximal decreases in the drying time of BL and US pretreatment groups were 40% and 33.3%, respectively. BL and US pretreatments significantly increased the effective diffusion coefficient and shortened the drying time because of the destruction of the cell structure. Low-field nuclear magnetic resonance analysis showed that free water is mainly lost during the initial drying stage, while solidified water is mainly lost during middle and late stages. According to the results of magnetic resonance imaging, the moisture distribution shows that cavitation from US acts on internal tissue, while BL disrupts the structure of external tissue. Texture data define the area enclosed by SC-D as uniform. After BL and US pretreatment, the hardness of dried cantaloupe decreased and the uniformity increased significantly. The best pretreatment process for cantaloupe at 80°C was 10 min of US. These findings provide a reference for testing in the industrial production of dried cantaloupe and are deeply relevant for practice.

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