Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 64
Filtrar
Mais filtros

Base de dados
Tipo de documento
Intervalo de ano de publicação
1.
Gut ; 72(5): 918-928, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36627187

RESUMO

OBJECTIVE: Gestational diabetes mellitus (GDM) is a condition in which women without diabetes are diagnosed with glucose intolerance during pregnancy, typically in the second or third trimester. Early diagnosis, along with a better understanding of its pathophysiology during the first trimester of pregnancy, may be effective in reducing incidence and associated short-term and long-term morbidities. DESIGN: We comprehensively profiled the gut microbiome, metabolome, inflammatory cytokines, nutrition and clinical records of 394 women during the first trimester of pregnancy, before GDM diagnosis. We then built a model that can predict GDM onset weeks before it is typically diagnosed. Further, we demonstrated the role of the microbiome in disease using faecal microbiota transplant (FMT) of first trimester samples from pregnant women across three unique cohorts. RESULTS: We found elevated levels of proinflammatory cytokines in women who later developed GDM, decreased faecal short-chain fatty acids and altered microbiome. We next confirmed that differences in GDM-associated microbial composition during the first trimester drove inflammation and insulin resistance more than 10 weeks prior to GDM diagnosis using FMT experiments. Following these observations, we used a machine learning approach to predict GDM based on first trimester clinical, microbial and inflammatory markers with high accuracy. CONCLUSION: GDM onset can be identified in the first trimester of pregnancy, earlier than currently accepted. Furthermore, the gut microbiome appears to play a role in inflammation-induced GDM pathogenesis, with interleukin-6 as a potential contributor to pathogenesis. Potential GDM markers, including microbiota, can serve as targets for early diagnostics and therapeutic intervention leading to prevention.


Assuntos
Diabetes Gestacional , Microbiota , Gravidez , Feminino , Humanos , Diabetes Gestacional/diagnóstico , Terceiro Trimestre da Gravidez , Inflamação , Citocinas
2.
Pestic Biochem Physiol ; 197: 105684, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38072541

RESUMO

Beauveria bassiana is an entomopathogenic fungus widely used in agriculture to reduce populations of various pests. However, when agricultural waste is utilized for organic recycling, B. bassiana has the potential to impact recycling performance, by affecting the survival, and body mass of decomposing organisms (such as insect's larvae). Additionally, in natural conditions where decayed organic matter contains a high load of different entomopathogenic organisms, larval growth may be affected when consumed or in contact. In a laboratory study, we aimed to comprehend the effects of B. bassiana on the growth characteristics and larval metabolism of the black soldier fly larvae, which is a known decomposing insect. The experiments used both feeding (mixing the spores with the diet, hereafter BF) and contact treatments (by dipping the larva in the spores solution, hereafter BD), and were compared to a water-treated control group. The BF treatment significantly reduced larval body weight, adult emergence, and adult weight compared to both the control and the BD treatment. Furthermore, an analysis of hemolymph metabolites, categorized by class, indicated a higher accumulation of metabolites belonging to the purine and purine derivative classes, as well as carboxylic acids and their derivatives, including peptides and oligopeptides, indicating potential disruption of protein synthesis or degradation caused by the BF treatment. Pathway enrichment analysis showed significant alterations in purine metabolism and D-Arginine and D-ornithine metabolism compared to the control. Taurine and hypotaurine metabolism were significantly altered in the BD treatment compared to the control but not significantly enriched in the BF treatment. Our results suggest that the BF treatment impairs protein synthesis or degradation, affecting larval growth characteristics. Future studies should explore innate immunity-related gene expression and antimicrobial peptide production in BSF larvae to understand their immunity to pathogens.


Assuntos
Beauveria , Dípteros , Animais , Larva/genética , Controle Biológico de Vetores/métodos , Purinas
3.
Molecules ; 27(9)2022 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-35566094

RESUMO

The aim of the present study was to identify the structure of active compounds in Cyathus stratus that previously demonstrated anti-pancreatic cancer activity. The active compounds were purified from a crude extract by a series of RP-18 preparative chromatography using homemade octadecyl silica gel column. HPLC injection of the crude extract revealed a chromatogram with three main peaks with retention times (RT) 15.6, 18.2, and 22.5 min. Each fraction that exhibited promising activity in vitro was further separated using various available chromatographic techniques. The purified compound with the ultimate anti-cancer activity appeared at RT of 15.8 in the HPLC chromatogram with more than 90% purity. The main peak at the mass spectra appeared at m/z = 446.2304 with the calculated molecular formula of C25H34O7. One- and two-dimensional NMR analyses indicated that the structure of the active molecule (peak 15.8 min in HPLC) was identified as striatal C. Exposure of human pancreatic cancer cells to purified striatal C resulted in induction of apoptosis. Further studies are needed in order to develop a method for the synthesis of striatal in order to use it in clinical studies for treatment of cancer.


Assuntos
Cyathus , Neoplasias Pancreáticas , Apoptose , Cromatografia Líquida de Alta Pressão , Misturas Complexas , Humanos , Neoplasias Pancreáticas/tratamento farmacológico , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Neoplasias Pancreáticas
4.
Plant J ; 102(2): 246-261, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-31782847

RESUMO

With the objective of studying the role of glutathione reductase (GR) in the accumulation of cysteine and methionine, we generated transgenic tobacco and Arabidopsis lines overexpressing the cytosolic AtGR1 and the plastidic AtGR2 genes. The transgenic plants had higher contents of cysteine and glutathione. To understand why cysteine levels increased in these plants, we also used gr1 and gr2 mutants. The results showed that the transgenic plants have higher levels of sulfite, cysteine, glutathione and methionine, which are downstream to adenosine 5' phosphosulfate reductase (APR) activity. However, the mutants had lower levels of these metabolites, while the sulfate content increased. A feeding experiment using 34 SO42- also showed that the levels of APR downstream metabolites increased in the transgenic lines and decreased in gr1 compared with their controls. These findings, and the results obtained from the expression levels of several genes related to the sulfur pathway, suggest that GR plays an essential role in the sulfur assimilation pathway by supporting the activity of APR, the key enzyme in this pathway. GR recycles the oxidized form of glutathione (GSSG) back to reduce glutathione (GSH), which serves as an electron donor for APR activity. The phenotypes of the transgenic plants and the mutants are not significantly altered under non-stress and oxidative stress conditions. However, when germinating on sulfur-deficient medium, the transgenic plants grew better, while the mutants were more sensitive than the control plants. The results give substantial evidence of the yet unreported function of GR in the sulfur assimilation pathway.


Assuntos
Proteínas de Arabidopsis/metabolismo , Arabidopsis/enzimologia , Glutationa Redutase/metabolismo , Glutationa/metabolismo , Enxofre/metabolismo , Arabidopsis/genética , Proteínas de Arabidopsis/genética , Cisteína/metabolismo , Glutationa Redutase/genética , Mutação , Oxirredução , Plantas Geneticamente Modificadas , Sulfatos/metabolismo , Nicotiana/enzimologia , Nicotiana/genética
5.
BMC Surg ; 21(1): 346, 2021 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-34544418

RESUMO

BACKGROUND: Serum biochemical changes during laparoscopic surgery and positive pressure pneumoperitoneum (PP) may reflect mild oxidative stress due to the ischemia-reperfusion (I/R) mechanism. However, there is still a controversy regarding the exact mechanism of PP in creating oxidative stress and whether the induction of PP causes I/R effects at all. To elucidate this debated issue, we studied, for the first time, the changes of I/R parameters in the serum, in a pilot study, during laparoscopic cholecystectomy using a reliable, independent exogenous oxidative biomarker, together with common intrinsic biomarkers of oxidative stress. PATIENTS AND METHODS: Our study included 20 patients scheduled for elective laparoscopic cholecystectomy. We evaluated the levels of the extrinsic and endogenous markers for oxidative stress during awareness, under anesthesia, the end of surgery (abdominal CO2 evacuation), and 2 h afterward. RESULTS: After an initial increase in oxidative stress following anesthesia, we did not notice any further significant rise in the levels of the synthetic exogenous and the endogenous biomarkers at the end of the surgery and 2 h later on. However, a positive correlation was noted between the levels of both the intrinsic and extrinsic markers. CONCLUSIONS: In our study, the capability of the extrinsic biomarker to detect mild oxidative stress was not validated. Our study stresses the heterogeneous nature of the oxidative reactions and the diversity of the endogenous and exogenous biomarkers while detecting various biochemical patterns under mild oxidative stress, during the short period of laparoscopic surgery.


Assuntos
Colecistectomia Laparoscópica , Laparoscopia , Traumatismo por Reperfusão , Colecistectomia Laparoscópica/efeitos adversos , Humanos , Estresse Oxidativo , Projetos Piloto , Pneumoperitônio Artificial/efeitos adversos , Traumatismo por Reperfusão/diagnóstico , Traumatismo por Reperfusão/etiologia
6.
Int J Mol Sci ; 22(23)2021 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-34884848

RESUMO

Cancer stem cells (CSC) have been identified in several types of solid tumors. In some cases, CSC may be the source of all the tumor cells, the cause of the tumor's resistance to chemotherapeutic agents, and the source of metastatic cells. Thus, a combination therapy targeting non-CSC tumor cells as well as specifically targeting CSCs holds the potential to be highly effective. Natural products (NPs) have been a historically rich source of biologically active compounds and are known for their ability to influence multiple signaling pathways simultaneously with negligible side effects. In this review, we discuss the potential of NPs in targeting multiple signaling pathways in CSC and their potential to augment the efficacy of standard cancer therapy. Specifically, we focus on the anti-CSC activities of flavonoids, FDA-approved drugs originating from natural sources. Additionally, we emphasize the potential of NPs in targeting microRNA-mediated signaling, given the roles of microRNA in the maintenance of the CSC phenotype.


Assuntos
Produtos Biológicos/farmacologia , Células-Tronco Neoplásicas/efeitos dos fármacos , Membro 2 da Subfamília G de Transportadores de Cassetes de Ligação de ATP/química , Membro 2 da Subfamília G de Transportadores de Cassetes de Ligação de ATP/metabolismo , Aldeído Desidrogenase/metabolismo , Produtos Biológicos/química , Produtos Biológicos/metabolismo , Produtos Biológicos/uso terapêutico , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Transição Epitelial-Mesenquimal/efeitos dos fármacos , Flavonoides/química , Flavonoides/farmacologia , Flavonoides/uso terapêutico , Humanos , MicroRNAs/metabolismo , Neoplasias/tratamento farmacológico , Neoplasias/patologia , Células-Tronco Neoplásicas/metabolismo
7.
BMC Genomics ; 20(1): 606, 2019 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-31337340

RESUMO

BACKGROUND: Quercetin is a polyphenol of great interest given its antioxidant activity and involvement in the immune response. Although quercetin has been well studied at the molecular level as a gene regulator and an activator of specific cellular pathways, not much attention has been given to its mechanism of action at the genome-wide level. The present study aims to characterize quercetin's interaction with cellular DNA and to show its subsequent effect on downstream transcription. RESULTS: Two massive parallel DNA-sequencing technologies were used: Chem-seq and RNA-seq. We demonstrate that upon binding to DNA or genome-associated proteins, quercetin acts as a cis-regulatory transcription factor for the expression of genes that are involved in the cell cycle, differentiation and development. CONCLUSIONS: Such findings could provide new and important insights into the mechanisms by which the dietary polyphenol quercetin influences cellular functions.


Assuntos
Regulação da Expressão Gênica/efeitos dos fármacos , Monócitos/citologia , Quercetina/farmacologia , Proteínas de Ciclo Celular/genética , Diferenciação Celular , DNA , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Fatores de Transcrição
8.
Arch Gynecol Obstet ; 298(2): 405-413, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29938347

RESUMO

PURPOSE: To evaluate (a) the properties of high-density lipoproteins (HDL)/cholesterol, which include apolipoprotein A-1 (ApoA1) and paraoxonase1 (PON1), both are negative predictors of cardiovascular risk and (b) HDL function, among women with preeclampsia (PE). PE is a multi-system disorder, characterized by onset of hypertension and proteinuria or other end-organ dysfunction in the second half of pregnancy. Preeclampsia is associated with increased risk for later cardiovascular disease. The inverse association between HDL, cholesterol levels and the risk of developing atherosclerotic cardiovascular disease is well-established. METHODS: Twenty-five pregnant women [19 with PE and 6 with normal pregnancy (NP)] were recruited during admission for delivery. HDL was isolated from blood samples. PON1 activity and HDL were analyzed. An in vitro model of endothelial cells was used to evaluate the effect of HDL on the transcription response of vascular cell adhesion molecule-1 (VCAM-1) and endothelial nitric oxide synthase (eNOS) mRNA expression. RESULTS: PON1 activity (units/ml serum) was lower in the PE group compared to normal pregnancy (NP) (6.51 ± 0.73 vs. 9.98 ± 0.54; P = 0.015). Increased ApoA1 was released from PE-HDL as compared to NP-HDL (3.54 ± 0.72 vs. 0.89 ± 0.35; P = 0.01). PE-HDL exhibited increased VCAM-1 mRNA expression and decreased eNOS mRNA expression on TNF-α stimulated endothelial cells as compared to NP-HDL. CONCLUSIONS: HDL from women with PE reduced PON1 activity and increased ApoA1 release from HDL particles. This process was associated with increased HDL diameter, suggesting impaired HDL anti-oxidant activity. These changes might contribute to higher long-term cardiovascular risks among women with PE.


Assuntos
Apolipoproteína A-I/metabolismo , Arildialquilfosfatase/metabolismo , Lipoproteínas HDL/fisiologia , Pré-Eclâmpsia/metabolismo , Adulto , Apolipoproteína A-I/fisiologia , Arildialquilfosfatase/fisiologia , Estudos de Casos e Controles , Colesterol/metabolismo , Feminino , Regulação da Expressão Gênica , Humanos , Hipertensão/metabolismo , Lipoproteínas HDL/sangue , Óxido Nítrico Sintase Tipo III/genética , Óxido Nítrico Sintase Tipo III/metabolismo , Pré-Eclâmpsia/sangue , Pré-Eclâmpsia/fisiopatologia , Gravidez , Proteinúria/metabolismo , RNA Mensageiro/metabolismo , Fator de Necrose Tumoral alfa/metabolismo , Molécula 1 de Adesão de Célula Vascular/genética , Molécula 1 de Adesão de Célula Vascular/metabolismo
9.
Biochim Biophys Acta ; 1851(9): 1118-22, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25958017

RESUMO

Paraoxonase 1 (PON1) is an antiatherogenic high density lipoprotein-associated lactonase. Recent findings revealed that PON1 knockout mice have low blood pressure, which is negatively correlated with the level of 5,6-epoxyeicosatrienoic acid (5,6-EET), a cytochrome P450 -derived arachidonic acid metabolite. 5,6-EET is an endothelium-derived hyperpolarizing factor that causes arterial dilation. Under physiological conditions, 5,6-EET is unstable, transforming to its δ-lactone (5,6-δ-DHTL) that evades the degradation by soluble epoxide hydrolase (sEH), arguing for the existence of yet another enzyme that is responsible specifically for its hydrolysis. We therefore hypothesized that PON1 degrades the 5,6-δ-DHTL, and this specific PON1 lactonase activity thus decreases endothelial vasodilatation. The aim of the present study was to investigate the PON1-5,6-δ-DHTL relationship. A liquid chromatography mass spectrometry based method for 5,6-EET derivatives identification was developed. Tracking the lactonization of 5,6-EET in a physiological solution revealed that 5,6-EET was fully converted into 5,6-δ-DHTL. Incubation of 5,6-δ-DHTL with rePON1 resulted in 85.1±3.4% degradation of the substrate to 5,6 dihydroxytrienoic acid (5,6-DHET), while only 12.0±8.7% hydrolysis was detected in the absence of PON1. Accordingly, the levels of 5,6-DHTL were found to be significantly higher in the PON1KO mice than in the wild type mice. Kinetic analysis revealed values of Vmax=0.021±0.01µM/s and Km=150.99±62.1µM. Calculation of the docking energy suggested possible interaction of the 5,6-δ-DHTL in the catalytic region of PON1 with free energy of-5.57 Kcal/mol, preferentially for the (S) enantiomer. These findings demonstrate that 5,6-δ-DHTL is a PON1 substrate and imply that the 5,6-EET vasodilation effect may be impaired by PON1.


Assuntos
Ácido 8,11,14-Eicosatrienoico/análogos & derivados , Arildialquilfosfatase/química , Ácidos Hidroxieicosatetraenoicos/metabolismo , Rim/química , Ácido 8,11,14-Eicosatrienoico/metabolismo , Animais , Ácido Araquidônico/metabolismo , Arildialquilfosfatase/genética , Arildialquilfosfatase/metabolismo , Domínio Catalítico , Epóxido Hidrolases/genética , Epóxido Hidrolases/metabolismo , Expressão Gênica , Rim/metabolismo , Cinética , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Simulação de Acoplamento Molecular , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Especificidade por Substrato , Termodinâmica , Vasodilatação
10.
Immunology ; 144(1): 116-26, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25041614

RESUMO

The immune response against hapten is T-cell-dependent, and so requires the uptake, processing and presentation of peptides on MHC class II molecules by antigen-presenting cells to the specific T cell. Some haptens, following conjugation to the available free amines on the surface of the carrier protein, can reduce its immunogenicity. The purpose of this study was to explore the mechanism by which this occurs. Four proteins were tested as carriers and six molecules were used as haptens. The immune response to the carrier proteins was reduced > 100-fold by some of the haptens (termed carrier immunogenicity reducing haptens--CIRH), whereas other haptens did not influence the protein immunogenicity (carrier immunogenicity non-reducing haptens--nCIRH). Conjugation of the protein to a CIRH affected protein degradation by lysosomal cathepsins, leading to the generation of peptides that differ in length and sequence from those derived from the same native protein or that protein modified with nCIRH. Injection of CIRH-conjugated protein into mice induced an increase in the population of regulatory T cells. The results of this study provide a putative mechanism of action for the reduction of immune response to haptenated proteins.


Assuntos
Apresentação de Antígeno/efeitos dos fármacos , Portadores de Fármacos/farmacologia , Haptenos/farmacologia , Peptídeos/farmacologia , Linfócitos T Reguladores/imunologia , Animais , Catepsinas/imunologia , Haptenos/imunologia , Lisossomos/imunologia , Camundongos , Camundongos Endogâmicos BALB C , Peptídeos/imunologia
11.
Biochem Biophys Res Commun ; 446(3): 709-13, 2014 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-24393847

RESUMO

Atherosclerosis is the most common cause of mortality in the Western world, contributing to about 50% of all deaths. Atherosclerosis is characterized by deposition of lipids onto the coronary or carotid arterial wall and formation of an atherosclerotic plaque. Atherosclerotic plaques are categorized into two groups: symptomatic and asymptomatic. The symptomatic plaques tend to be unstable and prone to rupture, and are associated with an increase in ischemic events. Oxysterols, products of cholesterol oxidation, are cytotoxic materials. Their level and type may be associated with plaque formation, development and stability. Oxysterols stimulate the formation of foam cells, advance atherosclerotic plaque progression, and contribute to plaque vulnerability and instability due to their cytotoxicity and their ability to induce cell apoptosis. Studies indicate that plasma 7ß-OH CH level can be used as a biomarker for detecting carotid and coronary artery disease. Further clinical studies are needed to evaluate the potential of oxysterols for use as biomarkers for plaque vulnerability and instability. The identification of biomarkers in the blood that can distinguish between symptomatic and asymptomatic plaques remains an unresolved issue.


Assuntos
Biomarcadores/metabolismo , Hidroxicolesteróis/metabolismo , Placa Aterosclerótica/metabolismo , Placa Aterosclerótica/patologia , Biomarcadores/análise , Colesterol/análogos & derivados , Colesterol/análise , Colesterol/metabolismo , Doença da Artéria Coronariana/sangue , Humanos , Hidroxicolesteróis/sangue , Cetocolesteróis/metabolismo
12.
Biochem Biophys Res Commun ; 444(3): 354-9, 2014 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-24462770

RESUMO

Post-translational modification (PTM) of proteins plays a crucial role in health and disease by affecting numerous aspects of protein structure, function, stability and subcellular localization. Protein S-nitrosylation is one type of PTM that involves the covalent modification of cysteine sulfhydryl groups with nitric oxide (NO) and has a regulatory impact similar to phosphorylation. The enzyme paraoxonase 1 (PON1) is associated with high-density lipoprotein (HDL), and is responsible for many of HDL's antiatherogenic properties. The enzyme contains a free thiol group at Cys-284 which can also be modified covalently. As part of our effort to study the effect of PTMs on PON1 activities and properties and its implication for cardiovascular disease, we examined PON1's ability to undergo S-nitrosylation on its free Cys-284. Recombinant (re) PON1 was trans-S-nitrosylated by several NO donors, glutathione-NO (GSNO) was found to be the most effective. The S-nitrosylated rePON1 was analyzed by Q-TOF LC/MS and by Saville-Griess assay: the two analytical methods revealed closely similar results. rePON1 was also nitrosylated by nitrosylated human serum albumin (HSA-NO) via protein-protein trans-nitrosylation. HSA-NO transferred an NO group to rePON1 much more efficiently than GSNO with the formation of a higher than 70% rePON-NO when incubated with a 40-fold excess of a HSA-NO/HSA mixture. RePON1-NO was relatively stable: storage for 3days at 37°C resulted in only 25% decomposition. This is the first report of PON1's S-nitrosylation via GSNO and HSA-NO.


Assuntos
Arildialquilfosfatase/biossíntese , Doadores de Óxido Nítrico/metabolismo , Arildialquilfosfatase/metabolismo , Cromatografia Líquida , Humanos , Espectrometria de Massas , Fosforilação , S-Nitrosoglutationa/metabolismo
13.
Biofactors ; 50(3): 608-618, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38135490

RESUMO

The high-density lipoprotein (HDL)-associated enzyme paraoxonase 1 (PON1) is expressed almost exclusively in the liver and is then transported by HDL to the peripheral tissues. The lipophilic nature of PON1 enables its easy exchange between the lipoprotein and cell membranes in a process that is dependent on the HDL receptor scavenger receptor class B, type 1 (SR-B1). In endothelial cells, PON1 binding to the cell membrane leads to its internalization by endocytosis and subsequent lysosomal degradation. PON1 is a "promiscuous" enzyme with unusually broad substrate specificity in vitro, but its actual function and substrate are still unknown. The enzyme requires a lipid environment and becomes completely inactive upon delipidation. However, when PON1 binds HDL, its active site faces the lipoprotein's core and is inaccessible to external substrates. Hence, the HDL-bound PON1 is inactive toward substrates outside the particle's lipid core and is rapidly degraded and becomes inactive upon internalization. Consequently, the enzyme is only active in the cell membrane during its transit from HDL to the cytoplasm. To assign a function to PON1, we investigated whether it is a palmitoyl-protein thioesterase (PPT) that can hydrolyze the palmitoyl moieties of membrane proteins involved in HDL and cholesterol transport, such as SR-B1, ABCA1, or their neighboring caveola proteins to facilitate the release of HDL or trigger its endocytosis. This study shows that PON1 can hydrolyze palmitoyl-cysteine thioester bonds in vitro, has direct or indirect PPT activity in vivo, and can significantly decrease the presence of SR-B1 in the endothelial membrane.


Assuntos
Arildialquilfosfatase , Membrana Celular , Lipoproteínas HDL , Receptores Depuradores Classe B , Tioléster Hidrolases , Arildialquilfosfatase/metabolismo , Arildialquilfosfatase/genética , Tioléster Hidrolases/metabolismo , Tioléster Hidrolases/genética , Humanos , Membrana Celular/metabolismo , Receptores Depuradores Classe B/metabolismo , Receptores Depuradores Classe B/genética , Lipoproteínas HDL/metabolismo , Células Endoteliais/metabolismo , Células Endoteliais/enzimologia , Células Endoteliais da Veia Umbilical Humana , Animais , Endocitose/fisiologia
14.
Chem Phys Lipids ; 258: 105367, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-38103770

RESUMO

High-density lipoprotein (HDL) has traditionally been acknowledged as "good cholesterol" owing to its significant association with a decreased risk of atherosclerosis. This association is primarily attributed to HDL's direct involvement in cholesterol efflux capacity, which plays a pivotal role in reverse cholesterol transport. A novel active compound from Nannochloropsis microalgae termed lyso-DGTS, a lipid that contains EPA fatty acids, was previously isolated and found to increase paraoxonase 1 activity and enhance HDL-mediated cholesterol efflux and HDL-induced endothelial nitric oxide release. Here, the effect of different lyso-DGTS derivatives and analogs on HDL-mediated cholesterol efflux from macrophages was examined, and the mechanism was explored. Structure-activity relationships were established to characterize the essential lipid moieties responsible for HDL-mediated cholesterol efflux from macrophages. Lyso-DGTS, 1-carboxy-N-N-N-trimethyl-3-oleamidopropan-1-aminium, and lyso-platelet-activating factor increased HDL-mediated cholesterol efflux from macrophages dose-dependently, mainly via the ABCA1-mediated cholesterol efflux pathway. The effect of lyso-DGTS derivatives and analogs on the surface polarity of HDL was examined using the Laurdan generalized polarization (GP) assay. A reverse Pearson linear regression was obtained between Laurdan GP values and HDL-mediated cholesterol efflux. Because the incorporation of bioactive lipids into the surface phospholipid layer of HDL leads to a decrease in Laurdan GP, these bioactive lipids may induce lower phospholipid ordering and greater free space on the HDL particle surface, thereby enhancing apolipoprotein A1 binding to the ABCA1 receptor and improving ABCA1 cholesterol-mediated efflux. Our findings suggest a beneficial effect of lyso-DGTS and its bioactive lipid derivatives on increasing HDL-mediated cholesterol efflux activity from macrophages, which may impact atherosclerosis attenuation.


Assuntos
Aterosclerose , Lipoproteínas HDL , Humanos , HDL-Colesterol , Linhagem Celular , Macrófagos , Colesterol/metabolismo , Transportador 1 de Cassete de Ligação de ATP/metabolismo , Fosfolipídeos/metabolismo , Apolipoproteína A-I
15.
Cells ; 13(3)2024 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-38334596

RESUMO

INTRODUCTION: Transcranial direct current stimulation (tDCS) is an evolving non-invasive neurostimulation technique. Despite multiple studies, its underlying molecular mechanisms are still unclear. Several previous human studies of the effect of tDCS suggest that it generates metabolic effects. The induction of metabolic effects by tDCS could provide an explanation for how it generates its long-term beneficial clinical outcome. AIM: Given these hints of tDCS metabolic effects, we aimed to delineate the metabolic pathways involved in its mode of action. METHODS: To accomplish this, we utilized a broad analytical approach of co-analyzing metabolomics and transcriptomic data generated from anodal tDCS in rat models. Since no metabolomic dataset was available, we performed a tDCS experiment of bilateral anodal stimulation of 200 µA for 20 min and for 5 consecutive days, followed by harvesting the brain tissue below the stimulating electrode and generating a metabolomics dataset using LC-MS/MS. The analysis of the transcriptomic dataset was based on a publicly available dataset. RESULTS: Our analyses revealed that tDCS alters the metabolic profile of brain tissue, affecting bioenergetic-related pathways, such as glycolysis and mitochondrial functioning. In addition, we found changes in calcium-related signaling. CONCLUSIONS: We conclude that tDCS affects metabolism by modulating energy production-related processes. Given our findings concerning calcium-related signaling, we suggest that the immediate effects of tDCS on calcium dynamics drive modifications in distinct metabolic pathways. A thorough understanding of the underlying molecular mechanisms of tDCS has the potential to revolutionize its applicability, enabling the generation of personalized medicine in the field of neurostimulation and thus contributing to its optimization.


Assuntos
Estimulação Transcraniana por Corrente Contínua , Humanos , Ratos , Animais , Estimulação Transcraniana por Corrente Contínua/métodos , Cálcio , Cromatografia Líquida , Espectrometria de Massas em Tandem , Perfilação da Expressão Gênica
16.
Bioorg Med Chem ; 21(11): 3348-55, 2013 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-23623675

RESUMO

Flavonoids are plant phenolic secondary metabolites that are widely distributed in the human diet. These antioxidants have received much attention because of their neuroprotective, cardioprotective, and chemopreventive actions. While a major focus has been on the flavonoids' antioxidant properties, there is an emerging view that many of the potential health benefits of flavonoids and their in vivo metabolites are due to modulatory actions in cells through direct interactions with proteins, and not necessarily due to their antioxidant function. This view relies on the observations that flavonoids are present in the circulation at very low concentrations, which are not sufficient to exert effective antioxidant effects. The enzyme paraoxonase 1 (PON1) is associated with high-density lipoprotein (HDL), and is responsible for many of HDLs' antiatherogenic properties. We previously showed that the flavonoid glabridin binds to rePON1 and affects the enzyme's 3D structure. This interaction protects the enzyme from inhibition by an atherogenic component of the human carotid plaque. Here, we broadened our study to an investigation of the structure-activity relationships (SARs) of 12 flavonoids from different subclasses with rePON1 using Trp-fluorescence quenching, modeling calculations and Cu(2+)-induced low-density lipoprotein (LDL) oxidation methods. Our findings emphasize the 'protein-binding' mechanism by which flavonoids exert their beneficial biological role toward rePON1. Flavonoids' capacity to interact with the enzyme's rePON1 hydrophobic groove mostly dictates their pro/antioxidant behavior.


Assuntos
Arildialquilfosfatase/química , Flavonoides/química , Lipoproteínas HDL/química , Lipoproteínas LDL/química , Relação Estrutura-Atividade , Sítio Alostérico , Cobre/química , Humanos , Simulação de Acoplamento Molecular , Oxirredução , Ligação Proteica , Conformação Proteica , Proteínas Recombinantes/química , Espectrometria de Fluorescência , Triptofano/química
17.
Mol Biol Rep ; 40(3): 2205-13, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23212614

RESUMO

Chronic myeloid leukemia (CML) is characterized by the presence of p210(Bcr-Abl) which exhibits an abnormal kinase activity. Selective Abl kinase inhibitors have been successfully established for the treatment of CML. Despite high rates of clinical response, CML patients can develop resistance against these kinase inhibitors mainly due to point mutations within the Abl protein kinase domain. Previously, we have identified oleic acid as the active component in the mushroom Daedalea gibbosa that inhibited the kinase activity of Bcr-Abl. Here, we report that the oleyl amine derivatives, S-1-(1-Hydroxymethyl-2-methyl-propyl)-3-octadec-9-enyl-urea [oleylaminocarbonyl-L-N-valinol,oroleylaminocarbonyl-S-2-isopropyl-N-ethanolamine,oleylamine-carbonyl-L-valinol] (cpd 6) and R-1-(1-Hydroxymethyl-2-methyl-propyl)-3-octadec-9-enyl-urea [oleylamineocarbonyl-D-N-valinol, oleylaminocarbonyl-R-2-isopropyl-N-ethanolamine, or oleylamine-carbonyl-D-valinol] (cpd 7), inhibited the activity of the native and T315I mutated Bcr-Abl. Furthermore, cpd 6 and 7 exhibited higher activity towards the oncogenic Bcr-Abl in comparison to native c-Abl in SupB15 Ph-positive ALL cell line.


Assuntos
Proteínas de Fusão bcr-abl/genética , Proteínas de Fusão bcr-abl/metabolismo , Mutação , Leucemia-Linfoma Linfoblástico de Células Precursoras/genética , Leucemia-Linfoma Linfoblástico de Células Precursoras/metabolismo , Inibidores de Proteínas Quinases/farmacologia , Valina/análogos & derivados , Aminas/química , Linhagem Celular Tumoral , Relação Dose-Resposta a Droga , Proteínas de Fusão bcr-abl/química , Humanos , Janus Quinase 2/genética , Janus Quinase 2/metabolismo , Conformação Molecular , Simulação de Acoplamento Molecular , Simulação de Dinâmica Molecular , Fosforilação/efeitos dos fármacos , Ligação Proteica , Inibidores de Proteínas Quinases/química , Ensaio Tumoral de Célula-Tronco , Valina/química , Valina/farmacologia
18.
Heliyon ; 9(3): e13756, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36895384

RESUMO

Tropomyosin receptor kinase B (TrkB) serves as a pivotal factor in various cancers. To identify novel natural compounds with TrkB-inhibiting properties, a screening approach was applied using extracts from a collection of wild and cultivated mushroom fruiting bodies, and Ba/F3 cells that ectopically express TrkB (TPR-TrkB). We selected mushroom extracts that selectively inhibited proliferation of the TPR-TrkB cells. We then evaluated the ability of exogenous interleukin 3 to rescue growth inhibition by the selected TrkB-positive extracts. An ethyl acetate extract of Auricularia auricula-judae actively inhibited auto-phosphorylation of TrkB. LC-MS/MS analysis of this extract revealed substances that might be responsible for the observed activity. This screening approach demonstrates, for the first time, that extracts originating from the mushroom A. auricula-judae exhibit TrkB-inhibition properties that might hold therapeutic potential for TrkB-positive cancers.

19.
Trends Mol Med ; 29(12): 983-995, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37806854

RESUMO

Multiomics studies offer accurate preventive and therapeutic strategies for atherosclerotic cardiovascular disease (ASCVD) beyond traditional risk factors. By using artificial intelligence (AI) and machine learning (ML) approaches, it is possible to integrate multiple 'omics and clinical data sets into tools that can be utilized for the development of personalized diagnostic and therapeutic approaches. However, currently multiple challenges in data quality, integration, and privacy still need to be addressed. In this opinion, we emphasize that joined efforts, exemplified by the AtheroNET COST Action, have a pivotal role in overcoming the challenges to advance multiomics approaches in ASCVD research, with the aim to foster more precise and effective patient care.


Assuntos
Aterosclerose , Doenças Cardiovasculares , Humanos , Inteligência Artificial , Doenças Cardiovasculares/diagnóstico , Doenças Cardiovasculares/genética , Doenças Cardiovasculares/terapia , Multiômica , Aterosclerose/diagnóstico , Aterosclerose/genética , Aterosclerose/terapia , Aprendizado de Máquina
20.
Oxid Med Cell Longev ; 2022: 2253478, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35464770

RESUMO

The recently described phenomenon of cholesterol-loaded low-density lipoproteins (LDL) entering the arterial wall from the lumen by transcytosis has been accepted as an alternative for the long-held concept that atherogenesis involves only passive LDL movement across an injured or dysfunctional endothelial barrier. This active transport of LDL can now adequately explain why plaques (atheromas) appear under an intact, uninjured endothelium. However, the LDL transcytosis hypothesis is still questionable, mainly because the process serves no clear physiological purpose. Moreover, central components of the putative LDL transcytosis apparatus are shared by the counter process of cholesterol efflux and reverse cholesterol transport (RCT) and therefore can essentially create an energy-wasting futile cycle and paradoxically be pro- and antiatherogenic simultaneously. Hence, by critically reviewing the literature, we wish to put forward an alternative interpretation that, in our opinion, better fits the experimental evidence. We assert that most of the accumulating cholesterol (mainly as LDL) reaches the intima not from the lumen by transcytosis, but from the artery's inner layers: the adventitia and media. We have named this directional cholesterol transport transmural cholesterol flux (TCF). We suggest that excess cholesterol, diffusing from the avascular (i.e., devoid of blood and lymph vessels) media's smooth muscle cells, is cleared by the endothelium through its apical membrane. A plaque is formed when this cholesterol clearance rate lags behind its rate of arrival by TCF.


Assuntos
Aterosclerose , Placa Aterosclerótica , Aorta/metabolismo , Colesterol , LDL-Colesterol , Humanos , Lipoproteínas LDL/metabolismo , Transcitose
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA