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1.
Science ; 368(6489)2020 04 24.
Artigo em Inglês | MEDLINE | ID: mdl-32327570

RESUMO

Protein quality control is essential for the proper function of cells and the organisms that they make up. The resulting loss of proteostasis, the processes by which the health of the cell's proteins is monitored and maintained at homeostasis, is associated with a wide range of age-related human diseases. Here, we highlight how the integrated stress response (ISR), a central signaling network that responds to proteostasis defects by tuning protein synthesis rates, impedes the formation of long-term memory. In addition, we address how dysregulated ISR signaling contributes to the pathogenesis of complex diseases, including cognitive disorders, neurodegeneration, cancer, diabetes, and metabolic disorders. The development of tools through which the ISR can be modulated promises to uncover new avenues to diminish pathologies resulting from it for clinical benefit.


Assuntos
Fator de Iniciação 2 em Eucariotos/metabolismo , Proteostase , Estresse Fisiológico , Fatores de Complexo Ternário/metabolismo , Acetamidas/química , Acetamidas/farmacologia , Animais , Cicloexilaminas/química , Cicloexilaminas/farmacologia , Fator de Iniciação 2 em Eucariotos/antagonistas & inibidores , Humanos , Imunidade , Doenças Metabólicas/metabolismo , Camundongos , Neoplasias/metabolismo , Fosfotransferases/metabolismo
2.
Nat Commun ; 11(1): 1304, 2020 03 11.
Artigo em Inglês | MEDLINE | ID: mdl-32161259

RESUMO

The integrated stress response (ISR) converges on eIF2α phosphorylation to regulate protein synthesis. ISR is activated by several stress conditions, including endoplasmic reticulum (ER) stress, executed by protein kinase R-like endoplasmic reticulum kinase (PERK). We report that ER stress combined with ISR inhibition causes an impaired maturation of several tyrosine kinase receptors (RTKs), consistent with a partial block of their trafficking from the ER to the Golgi. Other proteins mature or are secreted normally, indicating selective retention in the ER (sERr). sERr is relieved upon protein synthesis attenuation and is accompanied by the generation of large mixed disulfide bonded complexes, including ERp44. sERr was pharmacologically recapitulated by combining the HIV-protease inhibitor nelfinavir with ISRIB, an experimental drug that inhibits ISR. Nelfinavir/ISRIB combination is highly effective to inhibit the growth of RTK-addicted cell lines and hepatocellular (HCC) cells in vitro and in vivo. Thus, pharmacological sERr can be utilized as a modality for cancer treatment.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Carcinoma Hepatocelular/tratamento farmacológico , Retículo Endoplasmático/efeitos dos fármacos , Neoplasias Hepáticas/tratamento farmacológico , eIF-2 Quinase/metabolismo , Acetamidas/farmacologia , Acetamidas/uso terapêutico , Animais , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Sistemas CRISPR-Cas/genética , Carcinoma Hepatocelular/patologia , Linhagem Celular Tumoral , Cicloexilaminas/farmacologia , Cicloexilaminas/uso terapêutico , Retículo Endoplasmático/metabolismo , Estresse do Retículo Endoplasmático/efeitos dos fármacos , Técnicas de Inativação de Genes , Complexo de Golgi/metabolismo , Humanos , Neoplasias Hepáticas/patologia , Masculino , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Camundongos , Chaperonas Moleculares/genética , Chaperonas Moleculares/metabolismo , Nelfinavir/farmacologia , Nelfinavir/uso terapêutico , Ensaios Antitumorais Modelo de Xenoenxerto , eIF-2 Quinase/genética
3.
Ecotoxicol Environ Saf ; 194: 110360, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32151864

RESUMO

Ferroptosis is a newly identified form of cell death characterized by accumulation of intracellular iron and requirement of lipid peroxidation. However, whether arsenite triggers testicular cell death via ferroptosis remains unclear. In this study, after administrating of adult male mice with 0.5, 5 and 50 mg/L arsenite for six months via drinking water, the results showed that arsenite caused the pathological changes in mouse testis and significantly reduced the number of sperm. Mitochondrial injuries were observed as the major ultrastructural damages induced by arsenite, and these damages were accompanied by the apparent mitochondrial oxidative damage in the testis, manifested by accumulation of iron, production of reactive oxygen species and lipid peroxidation products. We also demonstrated that arsenite significantly activated ferroptosis-related signal pathways in the mouse testis. To further verify the results obtained in the animal model, GC-2spd cells were employed as the in vitro culture system. Consistently, the results revealed arsenite remarkably triggered the ferroptotic cell death in vitro, and inhibition of ferroptosis by ferrostatin-1 could attenuate this adverse effect in cells. These findings together indicate that arsenite can trigger oxidative stress thus leading to testicular cell death by ferroptosis, suggesting that inhibition of ferroptosis would be a potential strategy for treatment of arsenite-related male reproductive toxicity.


Assuntos
Arsenitos/toxicidade , Ferroptose/fisiologia , Estresse Oxidativo/fisiologia , Testículo/efeitos dos fármacos , Animais , Arsenitos/metabolismo , Morte Celular , Cicloexilaminas , Ferro/metabolismo , Peroxidação de Lipídeos/efeitos dos fármacos , Masculino , Camundongos , Mitocôndrias/metabolismo , Oxirredução , Fenilenodiaminas , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais/efeitos dos fármacos , Testículo/metabolismo , Testes de Toxicidade
4.
Artigo em Inglês | MEDLINE | ID: mdl-32213465

RESUMO

In this study, the use of switchable hydrophilicity solvent with a simple and low-cost lab-made device for the extraction procedure in homogeneous liquid-liquid microextraction is proposed for the first time in the determination of antidepressants in human urine. The antidepressants studied consisted of fluoxetine, amitriptyline, nortriptyline, imipramine, desipramine and sertraline. The optimization of the main parameters that can influence on the extraction efficiency was performed through multivariate approaches. The analytes were separated and identified by gas chromatography coupled to mass spectrometry (GC-MS). The optimal extraction conditions consisted of using N,N-dimethylcyclohexylamine (DMCHA) as the switchable hydrophilicity solvent (SHS), 500 µL of urine sample previously diluted with ultrapure water at 1:1 ratio (v/v), 200 µL of a mixture of SHS:HCl 6 mol L-1 (1:1 v/v), 600 µL of NaOH 10 mol L-1 and 3 min of extraction time. A volume of 40 µL of diphenylamine at concentration of 500 µg L-1 (20 ng) was used as internal standard. The method developed was in-house validated, providing coefficients of determination higher than 0.995 for all analytes, limits of detection (LOD) from 0.02 to 0.88 µg L-1, limits of quantification (LOQ) from 0.05 to 2.92 µg L-1, relative recoveries of 68 to 102%, intra-day precision from 0.5 to 15.9%, inter-day precision from 4.2 to 19.3%, selectivity and robustness. The method proposed was successfully applied in five human urine samples from a Toxicological Information Center located in Porto Alegre (Brazil). The results demonstrated that the µP-SHS-HLLME approach is highly cost-effective, rapid, simple and environmentally-friendly with satisfactory analytical performance.


Assuntos
Antidepressivos/urina , Adulto , Amitriptilina/urina , Cicloexilaminas/química , Desipramina/urina , Fluoxetina/urina , Cromatografia Gasosa-Espectrometria de Massas , Química Verde , Humanos , Interações Hidrofóbicas e Hidrofílicas , Imipramina/urina , Limite de Detecção , Microextração em Fase Líquida , Nortriptilina/urina , Sertralina/urina , Solventes/química
5.
Nat Cell Biol ; 22(2): 225-234, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-32029897

RESUMO

Energy stress depletes ATP and induces cell death. Here we identify an unexpected inhibitory role of energy stress on ferroptosis, a form of regulated cell death induced by iron-dependent lipid peroxidation. We found that ferroptotic cell death and lipid peroxidation can be inhibited by treatments that induce or mimic energy stress. Inactivation of AMP-activated protein kinase (AMPK), a sensor of cellular energy status, largely abolishes the protective effects of energy stress on ferroptosis in vitro and on ferroptosis-associated renal ischaemia-reperfusion injury in vivo. Cancer cells with high basal AMPK activation are resistant to ferroptosis and AMPK inactivation sensitizes these cells to ferroptosis. Functional and lipidomic analyses further link AMPK regulation of ferroptosis to AMPK-mediated phosphorylation of acetyl-CoA carboxylase and polyunsaturated fatty acid biosynthesis. Our study demonstrates that energy stress inhibits ferroptosis partly through AMPK and reveals an unexpected coupling between ferroptosis and AMPK-mediated energy-stress signalling.


Assuntos
Proteínas Quinases Ativadas por AMP/genética , Acetil-CoA Carboxilase/genética , Ferroptose/genética , Rim/enzimologia , Peroxidação de Lipídeos/genética , Traumatismo por Reperfusão/genética , Células A549 , Proteínas Quinases Ativadas por AMP/antagonistas & inibidores , Proteínas Quinases Ativadas por AMP/metabolismo , Acetil-CoA Carboxilase/metabolismo , Animais , Linhagem Celular Tumoral , Cicloexilaminas/farmacologia , Embrião de Mamíferos , Metabolismo Energético/efeitos dos fármacos , Metabolismo Energético/genética , Ácidos Graxos Insaturados/biossíntese , Ferroptose/efeitos dos fármacos , Fibroblastos/citologia , Fibroblastos/efeitos dos fármacos , Fibroblastos/metabolismo , Regulação da Expressão Gênica , Glucose/deficiência , Glucose/farmacologia , Humanos , Ferro/metabolismo , Rim/efeitos dos fármacos , Rim/patologia , Peroxidação de Lipídeos/efeitos dos fármacos , Células MCF-7 , Camundongos , Camundongos Transgênicos , Fenilenodiaminas/farmacologia , Fosforilação , Piperazinas/antagonistas & inibidores , Piperazinas/farmacologia , Cultura Primária de Células , Pirazóis/farmacologia , Pirimidinas/farmacologia , Traumatismo por Reperfusão/enzimologia , Traumatismo por Reperfusão/patologia , Transdução de Sinais , Estresse Fisiológico/efeitos dos fármacos , Estresse Fisiológico/genética
6.
Am J Physiol Heart Circ Physiol ; 318(3): H508-H518, 2020 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-31975626

RESUMO

Cigarette smoking is a major risk factor for aortic aneurysm and dissection; however, no causative link between smoking and these aortic disorders has been proven. In the present study, we investigated the mechanism by which cigarette smoke affects vascular wall cells and found that cigarette smoke extract (CSE) induced a novel form of regulated cell death termed ferroptosis in vascular smooth muscle cells (VSMCs). CSE markedly induced cell death in A7r5 cells and primary rat VSMCs, but not in endothelial cells, which was completely inhibited by specific ferroptosis inhibitors [ferrostatin-1 (Fer-1) and Liproxstatin-1] and an iron chelator (deferoxamine). CSE-induced VSMC death was partially inhibited by a GSH precursor (N-acetyl cysteine) and an NADPH oxidase inhibitor [diphenyleneiodonium chloride (DPI)], but not by inhibitors of pan-caspases (Z-VAD), caspase-1 (Z-YVAD), or necroptosis (necrostatin-1). CSE also upregulated IL-1ß, IL-6, TNF-α, matrix metalloproteinase (MMP)-2, MMP-9, and TIMP-1 (tissue inhibitor of metalloproteinase)in A7r5 cells, which was inhibited by Fer-1. Furthermore, CSE induced the upregulation of Ptgs2 mRNA, lipid peroxidation, and intracellular GSH depletion, which are key features of ferroptosis. VSMC ferroptosis was induced by acrolein and methyl vinyl ketone, major constituents of CSE. Furthermore, CSE caused medial VSMC loss in ex vivo aortas. Electron microscopy analysis showed mitochondrial damage and fragmentation in medial VSMCs of CSE-treated aortas. All of these manifestations were partially restored by Fer-1. These findings demonstrate that ferroptosis is responsible for CSE-induced VSMC death and suggest that ferroptosis is a potential therapeutic target for preventing aortic aneurysm and dissection.NEW & NOTEWORTHY Cigarette smoke extract (CSE)-induced cell death in rat vascular smooth muscle cells (VSMCs) was completely inhibited by specific ferroptosis inhibitors and an iron chelator. CSE also induced the upregulation of Ptgs2 mRNA, lipid peroxidation, and intracellular GSH depletion, which are key features of ferroptosis. CSE caused medial VSMC loss in ex vivo aortas. These findings demonstrate that ferroptosis is responsible for CSE-induced VSMC death.


Assuntos
Ferroptose/efeitos dos fármacos , Músculo Liso Vascular/metabolismo , Miócitos de Músculo Liso/metabolismo , Fumaça , Animais , Morte Celular/efeitos dos fármacos , Linhagem Celular , Cicloexilaminas/farmacologia , Desferroxamina/farmacologia , Células Endoteliais/efeitos dos fármacos , Células Endoteliais/metabolismo , Masculino , Metaloproteinase 2 da Matriz/metabolismo , Metaloproteinase 9 da Matriz/metabolismo , Miócitos de Músculo Liso/efeitos dos fármacos , NADPH Oxidases/metabolismo , Fenilenodiaminas/farmacologia , Quinoxalinas/farmacologia , Ratos , Ratos Sprague-Dawley , Sideróforos/farmacologia , Compostos de Espiro/farmacologia , Inibidor Tecidual de Metaloproteinase-1/metabolismo
7.
Food Chem ; 309: 125759, 2020 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-31706672

RESUMO

The effects of exogenous spermidine and dicyclohexylamine (DCHA, spermidine synthesis inhibitor) on the antioxidative system and energy status of germinating mung bean were investigated. Results showed that exogenous spermidine increased the content of total phenolic and ascorbic acid and the antioxidative activity, but reduced activities and gene expressions of peroxidase (POD) and catalase (CAT). These changes might be explained by increased H2O2 content and activities of succinic dehydrogenase (SDH), adenosine triphosphatases (ATPases), and cytochrome c oxidase (CCO), resulting in higher adenosine triphosphate (ATP) and energy charge (EC). Interestingly, spermidine down-regulated expressions of SDH, H+-ATPase, Ca2+-ATPase and CCO whilst DCHA reduced energy metabolism and induced the opposite effects to spermidine, except for ascorbic acid content. Inhibition was reversed by exogenous spermidine. In conclusion, spermidine induced the accumulation of H2O2, enhanced the antioxidative system and improved the energy metabolism to enhance the functional quality of mung bean sprouts.


Assuntos
Antioxidantes/química , Metabolismo Energético/efeitos dos fármacos , Espermidina/farmacologia , Vigna/química , Trifosfato de Adenosina/metabolismo , Antioxidantes/metabolismo , Catalase/metabolismo , Cicloexilaminas/farmacologia , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Germinação/efeitos dos fármacos , Peróxido de Hidrogênio/metabolismo , Peroxidases/metabolismo , Superóxido Dismutase/metabolismo , Vigna/crescimento & desenvolvimento , Vigna/metabolismo
8.
Int J Cancer ; 146(2): 510-520, 2020 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-31173656

RESUMO

Recent data suggest that rhabdomyosarcoma (RMS) cells might be vulnerable to oxidative stress-induced cell death. Here, we show that RMS are susceptible to cell death induced by Erastin, an inhibitor of the glutamate/cystine antiporter xc - that can increase reactive oxygen species (ROS) production via glutathione (GSH) depletion. Prior to cell death, Erastin caused GSH depletion, ROS production and lipid peroxidation. Importantly, pharmacological inhibitors of lipid peroxidation (i.e., Ferrostatin-1, Liproxstatin-1), ROS scavengers (i.e., α-Tocopherol, GSH) and the iron chelator Deferoxamine inhibited ROS accumulation, lipid peroxidation and cell death, consistent with ferroptosis. Interestingly, the broad-spectrum protein kinase C (PKC) inhibitor Bisindolylmaleimide I as well as the PKCα- and ß-selective inhibitor Gö6976 significantly reduced Erastin-induced cell death. Similarly, genetic knockdown of PKCα significantly protected RMS cells from Erastin-induced cell death. Furthermore, the broad-spectrum nicotinamide adenine dinucleotide phosphate-oxidase (NOX) inhibitor Diphenyleneiodonium and the selective NOX1/4 isoform inhibitor GKT137831 significantly decreased Erastin-stimulated ROS, lipid ROS and cell death. These data provide new insights into the molecular mechanisms of ferroptosis in RMS, contributing to the development of new redox-based treatment strategies.


Assuntos
Ferroptose/efeitos dos fármacos , Rabdomiossarcoma/tratamento farmacológico , Apoptose/efeitos dos fármacos , Morte Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Cicloexilaminas/metabolismo , Glutationa/metabolismo , Humanos , Peroxidação de Lipídeos/efeitos dos fármacos , Oxirredução/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Fenilenodiaminas/metabolismo , Piperazinas/metabolismo , Pirazóis/farmacologia , Piridinas/farmacologia , Espécies Reativas de Oxigênio/metabolismo , Rabdomiossarcoma/metabolismo , alfa-Tocoferol/metabolismo
9.
Int J Mol Sci ; 20(24)2019 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-31817853

RESUMO

The presence of the chromosomal rearrangement t(12;21)(ETV6-RUNX1) in childhood B-acute lymphoblastic leukemia (B-ALL) is an independent predictor of favorable prognosis, however relapses still occur many years later after stopping therapy, and patients often display resistance to current treatments. Since spleen tyrosine kinase (SYK), a cytosolic nonreceptor tyrosine kinase interacting with immune receptors, has been previously associated with malignant transformation and cancer cell proliferation, we aimed to assess its role in ETV6-RUNX1 cell survival and prognosis. We evaluated the effects on cell survival of three SYK inhibitors and showed that all of them, in particular entospletinib, are able to induce cell death and enhance the efficacy of conventional chemotherapeutics. By using reverse phase protein arrays we next revealed that activated SYK is upregulated at diagnosis in pediatric ETV6-RUNX1 patients who will experience relapse, and, importantly, hyperactivation is maintained at a high level also at relapse occurrence. We thus treated primary cells from patients both at diagnosis and relapse with the combination entospletinib + chemotherapeutics and observed that SYK inhibition is able to sensitize resistant primary cells to conventional drugs. Entospletinib could thus represent a new therapeutic option supporting conventional chemotherapy for relapsed ETV6-RUNX1 patients, and these evidences encourage further studies on SYK for treatment of other relapsed resistant acute lymphoblastic leukemia (ALL) subgroups.


Assuntos
Subunidade alfa 2 de Fator de Ligação ao Core/metabolismo , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Recidiva Local de Neoplasia/tratamento farmacológico , Proteínas de Fusão Oncogênica/metabolismo , Leucemia-Linfoma Linfoblástico de Células Precursoras B/tratamento farmacológico , Inibidores de Proteínas Quinases/farmacologia , Quinase Syk/antagonistas & inibidores , Proliferação de Células/efeitos dos fármacos , Criança , Subunidade alfa 2 de Fator de Ligação ao Core/genética , Cicloexilaminas/farmacologia , Humanos , Indazóis/farmacologia , Recidiva Local de Neoplasia/metabolismo , Recidiva Local de Neoplasia/patologia , Proteínas de Fusão Oncogênica/genética , Oxazinas/farmacologia , Leucemia-Linfoma Linfoblástico de Células Precursoras B/metabolismo , Leucemia-Linfoma Linfoblástico de Células Precursoras B/patologia , Pirazinas/farmacologia , Piridinas/farmacologia , Pirimidinas/farmacologia , Células Tumorais Cultivadas
10.
Molecules ; 24(23)2019 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-31810181

RESUMO

'Desymmetrization' of trans-1,2-diaminocyclohexane by treatment with α,ω-dihalogenated alkylation reagents leads to mono-NH2 derivatives ('primary-tertiary diamines'). Upon reaction with formaldehyde, these products formed monomeric formaldimines. Subsequently, reactions of the formaldimines with α-hydroxyiminoketones led to the corresponding 2-unsubstituted imidazole N-oxide derivatives, which were used here as new substrates for the in situ generation of chiral imidazol-2-ylidenes. Upon O-selective benzylation, new chiral imidazolium salts were obtained, which were deprotonated by treatment with triethylamine in the presence of elemental sulfur. Under these conditions, the intermediate imidazol-2-ylidenes were trapped by elemental sulfur, yielding the corresponding chiral non-enolizable imidazole-2-thiones in good yields. Analogous reaction sequences, starting with imidazole N-oxides derived from enantiopure primary amines, amino alcohols, and amino acids, leading to the corresponding 3-alkoxyimidazole-2-thiones were also studied.


Assuntos
Cicloexilaminas/química , Imidazóis/química , Óxidos/química
11.
PLoS One ; 14(12): e0227278, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31887216

RESUMO

The iron dependent, programmed cell death, ferroptosis was described first in tumour cells. It showed distinct features from the already known cell death forms such as apoptosis, necrosis and autophagy. The caspase independent cell death could be induced by the depletion of glutathione by erastin or by the inhibition of the lipid peroxide scavenger enzyme GPX4 by RSL3 and it was accompanied by the generation of lipid reactive oxygen species. Recently, ferroptosis-like cell death associated to glutathione depletion, lipid peroxidation and iron dependency could also be induced in plant cells by heat treatment. Unfortunately, the mediators and elements of the ferroptotic pathway have not been described yet. Our present results on Arabidopsis thaliana cell cultures suggest that acrolein, a lipid peroxide-derived reactive carbonyl species, is involved in plant ferroptosis-like cell death. The acrolein induced cell death could be mitigated by the known ferroptosis inhibitors such as Ferrostatin-1, Deferoxamine, α-Tocopherol, and glutathione. At the same time acrolein can be a mediator of ferroptosis-like cell death in plant cells since the known ferroptosis inducer RSL3 induced cell death could be mitigated by the acrolein scavenger carnosine. Finally, on the contrary to the caspase independent ferroptosis in human cells, we found that caspase-like activity can be involved in plant ferroptosis-like cell death.


Assuntos
Acroleína/metabolismo , Arabidopsis/fisiologia , Caspases/metabolismo , Ferroptose/fisiologia , Proteínas de Plantas/metabolismo , Acroleína/antagonistas & inibidores , Arabidopsis/citologia , Arabidopsis/efeitos dos fármacos , Carbolinas/farmacologia , Carnosina/farmacologia , Técnicas de Cultura de Células , Células Cultivadas , Cicloexilaminas/farmacologia , Desferroxamina/farmacologia , Ferroptose/efeitos dos fármacos , Glutationa/metabolismo , Ferro/metabolismo , Peroxidação de Lipídeos/efeitos dos fármacos , Peroxidação de Lipídeos/fisiologia , Fenilenodiaminas/farmacologia
12.
Molecules ; 25(1)2019 Dec 25.
Artigo em Inglês | MEDLINE | ID: mdl-31881683

RESUMO

In the present work, the effectiveness of switchable hydrophobicity solvents (SHSs) as extraction solvent (N,N-Dimethylcyclohexylamine (DMCA), N,N-Diethylethanamine (TEA), and N,N-Benzyldimethylamine (DMBA)) for a variety of emerging pollutants was evaluated. Different pharmaceutical products (nonsteroidal anti-inflammatory drugs (NSAIDs), hormones, and triclosan) were selected as target analytes, covering a range of hydrophobicity (LogP) of 3.1 to 5.2. The optimized procedure was used for the determination of the target pharmaceutical analytes in wastewater samples as model analytical problem. Absolute extraction recoveries were in the range of 51% to 103%. The presented method permits the determination of the target analytes at the low ng mL-1 level, ranging from 0.8 to 5.9 (except for Triclosan, 106 ng mL-1) with good precision (relative standard deviation lower than 6%) using high-pressure liquid chromatography (HPLC) combined with ultraviolet (DAD) and fluorescence (FLR) detection. The microextraction alternative resulted in a fast, simple, and green method for a wide variety of analytes in environmental water sample. The results suggest that this type of solvent turns out to be a great alternative for the determination of different analytes in relatively complex water samples.


Assuntos
Interações Hidrofóbicas e Hidrofílicas , Solventes/química , Águas Residuárias/química , Poluentes Químicos da Água/isolamento & purificação , Cicloexilaminas/química , Preparações Farmacêuticas/isolamento & purificação , Hidróxido de Sódio/química , Extração em Fase Sólida
13.
Molecules ; 24(23)2019 Nov 26.
Artigo em Inglês | MEDLINE | ID: mdl-31779081

RESUMO

The aim of this work was an investigation of the ability of gallic (GA) and ellagic (EA) acids, which are phenolic compounds encountered in various plants, to act as flame retardants (FRs) for epoxy resins. In order to improve their fireproofing properties, GA and EA were treated with boric acid (to obtain gallic acid derivatives (GAD) and ellagic acid derivatives (EAD)) to introduce borate ester moieties. Thermogravimetric analysis (TGA) highlighted the good charring ability of GA and EA, which was enhanced by boration. The grafting of borate groups was also shown to increase the thermal stability of GA and EA that goes up respectively from 269 to 528 °C and from 496 to 628 °C. The phenolic-based components were then incorporated into an epoxy resin formulated from diglycidyl ether of bisphenol A (DGEBA) and isophorone diamine (IPDA) (72, 18, and 10 wt.% of DGEBA, IPDA, and GA or EA, respectively). According to differential scanning calorimetry (DSC), the glass transition temperature (Tg) of the thermosets was decreased. Its values ranged from 137 up to 108 °C after adding the phenolic-based components. A cone calorimeter was used to evaluate the burning behavior of the formulated thermosets. A significant reduction of the peak of heat release rate (pHRR) for combustion was detected. Indeed, with 10 wt.% of GA and EA, pHRR was reduced by 12 and 44%, respectively, compared to that for neat epoxy resin. GAD and EAD also induced the decrease of pHRR values by 65 and 33%, respectively. In addition, a barrier effect was observed for the resin containing GAD. These results show the important influence of the biobased phenolic compounds and their boron derivatives on the fire behavior of a partially biobased epoxy resin.


Assuntos
Ácido Elágico/química , Resinas Epóxi/química , Retardadores de Chama/síntese química , Ácido Gálico/química , Compostos Benzidrílicos/química , Calorimetria/métodos , Cicloexilaminas/química , Fenóis/química , Temperatura de Transição
14.
Acta Biochim Biophys Sin (Shanghai) ; 51(11): 1134-1141, 2019 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-31650158

RESUMO

The widely used inhalation anesthetic, isoflurane, potentially induces neuronal injury in clinical practice. Previous studies showed multiple forms of cell death that resulted from isoflurane-induced cytotoxicity, but the precise underlying mechanism remains poorly understood. Ferroptosis has recently been identified as a non-apoptotic form of regulated cell death. Here, we found that ferroptosis inhibitors, ferrostatin-1 and deferoxamine mesylate (DFOM), showed great efficiency in maintaining cell viability in SH-SY5Y neuroblastoma cells exposed to a high concentration of isoflurane for 24 h. We also observed that cellular chelatable iron and lipid peroxidation were increased in a concentration-dependent manner in response to isoflurane. In addition, isoflurane upregulated Beclin1 phosphorylation, followed by the formation of a Beclin1-solute carrier family 7 member 11 (SLC7A11) complex, which affected the activity of cystine/glutamate antipoter and further regulated ferroptotic cell death. Accordingly, Beclin1 overexpression aggravated isoflurane-induced cell damage by upregulating ferroptosis. This phenomenon was significantly attenuated by silencing of Beclin1 in SH-SY5Y cells. These findings indicate that Beclin1 may regulate ferroptosis in a manner involving inhibition of glutamate exchange activity of system xc(-), which is implicated in isoflurane-induced toxicity. In particular, when isoflurane is administrated at high concentrations and for an extended duration, ferroptosis is more likely to play a crucial role in isoflurane-induced toxicity.


Assuntos
Proteína Beclina-1/fisiologia , Ferroptose , Ácido Glutâmico/metabolismo , Ferro/metabolismo , Isoflurano/toxicidade , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Cicloexilaminas/farmacologia , Desferroxamina/farmacologia , Humanos , Fenilenodiaminas/farmacologia
15.
Mar Drugs ; 17(8)2019 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-31416181

RESUMO

The objective of this research was to extract and prepare mycosporine-like amino acids (MAAs) and investigate the mechanism by which they act against UV-induced skin photoaging in Institute of Cancer Research (ICR ) mice. MAAs such as porphyra-334 and shinorine were extracted from Porphyra yezoensis, separated, and purified using column chromatography with SA-2 cation exchange resin. The effects of MAAs on the activity of endogenous antioxidant enzymes, namely total superoxide dismutase (T-SOD), glutathione peroxidase (GSH-Px), catalase (CAT), and malondialdehyde (MDA) were analyzed in mouse skin tissue. Pathological changes of skin tissue caused by ultraviolet radiation and the arrangement of collagen were observed by Hematoxylin-Eosin (HE) staining and scanning electron microscopy (SEM). Interleukin 1ß (IL-1ß), IL-6, and IL-10 were detected using the quantitative real-time reverse transcription-polymerase chain reaction (qPCR) and Enzyme Linked Immunosorbent Assay (ELISA). The concentration and expression of these proinflammatory cytokines was associated with the presence of nuclear factor (NF)-κB. The results show that MAA compounds from Porphyra yezoensis could suppress UV-induced photoaging of skin by inhibiting the reduction of endogenous antioxidant enzymes. Compared to the control group, the concentrations of SOD, GSH-Px, and CAT increased significantly in skin tissue homogenate following the external administration of MAAs (p < 0.05, p < 0.01), while the content of MDA decreased significantly (p < 0.05). Meanwhile, the administration of MAAs was associated with down-regulations in the concentration and mRNA expression of NF-κB, IL-1ß, IL-6, and IL-10. The results suggest that MAAs could protect skin from photodamage by increasing antioxidant enzyme activities and inhibiting inflammation.


Assuntos
Aminoácidos/farmacologia , Cicloexanonas/farmacologia , Cicloexilaminas/farmacologia , Glicina/análogos & derivados , Substâncias Protetoras/farmacologia , Dermatopatias/tratamento farmacológico , Raios Ultravioleta/efeitos adversos , Animais , Antioxidantes/metabolismo , Citocinas/metabolismo , Glicina/farmacologia , Inflamação/tratamento farmacológico , Inflamação/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos ICR , RNA Mensageiro/metabolismo , Pele/efeitos dos fármacos , Dermatopatias/metabolismo
16.
Environ Pollut ; 254(Pt A): 112937, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31401526

RESUMO

PM2.5 is becoming a worldwide environmental problem, which profoundly endangers public health, thus progressively capturing public attention this decade. As a fragile target of PM2.5, the underlying mechanisms of endothelial cell damage are still obscure. According to the previous microarray data and signaling pathway analysis, a new form of cell death termed ferroptosis in the current study is proposed following PM2.5 exposure. In order to verify the vital role of ferroptosis in PM2.5-induced endothelial lesion and further understand the potential mechanism involved, intracellular iron content, ROS release and lipid peroxidation, as well as biomarkers of ferroptosis were detected, respectively. As a result, uptake of particles increases cellular iron content and ROS production. Meanwhile, GSH depletion, and the decrease of GSH-Px and NADPH play significant roles in PM2.5-induced endothelial cell ferroptosis. Moreover, significantly changed expression of TFRC, FTL and FTH1 hinted that dysfunction of iron uptake and storage is a major inducer of ferroptosis. Importantly, index monitored above can be partially rescued by lipid peroxidation inhibitor ferrostatin-1 and iron chelator deferoxamine mesylate, which mediated antiferroptosis activity mainly depends on the restoration of antioxidant activity and iron metabolism. In conclusion, our data basically show that PM2.5 enhances ferroptosis sensitivity with increased ferroptotic events in endothelial cells, in which iron overload, lipid peroxidation and redox imbalance act pivotal roles.


Assuntos
Células Endoteliais/metabolismo , Ferroptose/fisiologia , Sobrecarga de Ferro/patologia , Ferro/toxicidade , Material Particulado/toxicidade , Antígenos CD/biossíntese , Apoferritinas/biossíntese , Apoptose/efeitos dos fármacos , Cicloexilaminas/farmacologia , Desferroxamina/farmacologia , Ferritinas/biossíntese , Glutationa/metabolismo , Humanos , Peroxidação de Lipídeos/efeitos dos fármacos , Oxirredução/efeitos dos fármacos , Fenilenodiaminas/farmacologia , Espécies Reativas de Oxigênio/metabolismo , Receptores da Transferrina/biossíntese , Transdução de Sinais/efeitos dos fármacos
17.
Invest Ophthalmol Vis Sci ; 60(10): 3422-3431, 2019 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-31390655

RESUMO

Purpose: The degenerative corneal disease keratoconus is a leading indicator for corneal transplant with an unknown etiology. We recently identified the activation of the integrated stress response (ISR) in ex vivo human corneas and in vitro cell culture. Utilizing small molecules to modulate the ISR we sought to investigate the effects of stimulating the ISR in healthy cells to recapitulate aspects of the in vitro keratoconic phenotype and whether relieving the ISR signaling would recover the disease phenotype. Methods: Corneal fibroblasts were extracted from patients undergoing corneal transplant or unaffected cadaverous donor limbal rings. Cells were exposed to the DNA damage-inducible protein (GADD34) inhibitor SAL003 to stimulate the ISR, or Trans-ISRIB to relieve ISR signaling pathway. Collagen production was assessed through hydroxyproline production, Sirius Red incorporation, or quantitative (q)PCR. Western blotting, hydroxyproline, and qPCR were used to assess components of the ISR pathway and collagen production. Results: ISR stimulation through SAL003 resulted in significant decrease of hydroxyproline and COL1A1 transcription and eventual apoptosis in normal fibroblasts. Patient (KC) fibroblast production of hydroxyproline was increased in response to ISRIB, while matrix metalloproteinase (MMP)9 production was lowered. The prospective biomarker of keratoconus prolactin-inducible factor was also upregulated in KC fibroblast cultures in response to ISRIB. Inflammatory markers TNFα and IL-1ß were unaffected. Conclusions: Activation of the ISR is sufficient to recapitulate many key aspects of the KC phenotype in unaffected cells in vitro. Inhibition of the ISR also relieves many of the hallmarks of KC in affected cells. Therefore, targeting of the ISR through small molecules is a potential therapeutic path for small molecule treatment of keratoconus.


Assuntos
Acetamidas/farmacologia , Ceratócitos da Córnea/efeitos dos fármacos , Cicloexilaminas/farmacologia , Inibidores Enzimáticos/farmacologia , Ceratocone/patologia , Estresse Fisiológico/efeitos dos fármacos , Western Blotting , Contagem de Células , Células Cultivadas , Colágeno Tipo I/genética , Ceratócitos da Córnea/metabolismo , Humanos , Hidroxiprolina/metabolismo , Metaloproteinase 2 da Matriz/genética , Metaloproteinase 9 da Matriz/genética , Fenótipo , Estudos Prospectivos , Proteína Fosfatase 1/antagonistas & inibidores , Reação em Cadeia da Polimerase em Tempo Real
18.
J Anal Toxicol ; 43(6): 497-503, 2019 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-31329888

RESUMO

Methoxetamine (MXE) and the arylcyclohexylamines 3-methoxy-PCP (3-MeO-PCP) and 4-methoxy-PCP (4-MeO-PCP) are substituted analogs of the dissociative psychoactive substances ketamine and phencyclidine (PCP), respectively. They have emerged on the new psychoactive substances (NPS) market as legal alternatives to these classically banned dissociatives. Little data has been published regarding the cross-reactivity of these NPS in PCP immunoassays (IAs). The aim of this work was to explore the possibilities of detecting 3-MeO-PCP, 4-MeO-PCP, MXE and ketamine in commercial IAs for PCP. The cross-reactivity study was performed in five different PCP IAs using urine-free, spiked samples and urine samples obtained from two 3-MeO-PCP overdose cases. 3-MeO-PCP and 4-MeO-PCP showed cross-reactivity (ranging from 1-143%) in all PCP IAs evaluated. MXE only showed very weak cross-reactivity (ranged from 0.04 to 0.25%) and ketamine was not detected in any PCP IA evaluated. Urine samples from the two overdose cases were positive for PCP in all IAs evaluated. The commercial PCP IAs evaluated exhibited utility as rapid, preliminary screening techniques for 3-MeO-PCP and 4-MeO-PCP, but not for ketamine. The low reactivity of MXE limits its detectability in the PCP IAs evaluated.


Assuntos
Imunoensaio , Fenciclidina , Psicotrópicos/urina , Líquidos Corporais , Cicloexanonas , Cicloexilaminas , Overdose de Drogas , Humanos , Ketamina , Fenciclidina/análogos & derivados
19.
Inorg Chem ; 58(14): 9326-9340, 2019 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-31247820

RESUMO

The synthesis of a novel class of cyclometalated gold(III) complexes supported by benzoylpyridine, benzylpyridine, and (1R,2R)-(+)-1,2-diaminocyclohexane (DACH) ligands, along with their crystal structures, is reported. These compounds provide a new scaffold to investigate biological properties of gold(III) complexes. The six complexes were prepared and characterized, following reactions of (C,N) cyclometalated gold(III) scaffolds, [Au(C^N)Cl2] with DACH, which yielded a new series of cyclometaled gold(III), 3-5, of the type [Au(C^NH)(DACH)2]+ and the nitrogen-substituted cyclometalated Au(III), 6-8, of the type [Au(C^N)(DACH)]2+. Antiproliferative activity of these complexes in a panel of cancer cells showed promising results with IC50 in the micromolar range and selectivity over normal epithelial cells, MRC5. Whereas 8 shows minimal interaction with superhelical DNA except at high gold concentrations of 500 µM, complex 5 does not show interaction even at 1000 µM. The complexes display significant uptake in OVCAR8 cancer cells within 200-1200 pmol/million cells with the exception of complex 4. Differential cellular uptake was observed for the complexes; for example, while 3 and 8 display significant uptake, 4 showed minimal uptake. The compounds proved to be stable under physiological conditions and were minimally affected by either glutathione or sodium ascorbate. Cell cycle studies reveal a G1 arrest induced by representative complexes. The results reveal that enhanced Au(III) stabilization promoted by combined cyclometalated and DACH ligands may offer ligand tuning insights for novel anticancer drug design.


Assuntos
Cicloexilaminas/química , Cicloexilaminas/farmacologia , Compostos de Ouro/química , Compostos de Ouro/farmacologia , Antineoplásicos/síntese química , Antineoplásicos/química , Antineoplásicos/farmacologia , Ácido Ascórbico/química , Linhagem Celular Tumoral , Simulação por Computador , Cristalografia por Raios X , Glutationa/química , Humanos , Ligantes , Modelos Químicos , Modelos Moleculares , Estrutura Molecular
20.
Biol Pharm Bull ; 42(8): 1337-1344, 2019 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-31167987

RESUMO

Diabetic cardiomyopathy (DCM) is a major complication of diabetes, and features myocardial fibrosis as its main pathological feature. Calcium sensing receptor (CaSR) is a G protein-coupled receptor, which involves in myocardial fibrosis by regulation of calcium homeostasis. Calhex231, the CaSR inhibitor, is not clear whether it regulates myocardial fibrosis in DCM. In the present study, type 1 diabetic (T1D) rats and primary neonatal rat cardiac fibroblasts were used to observe the role of Calhex231. In vivo experiments showed that in the T1D group, contractile dysfunction and the deposition of collagen I and III were obvious after 12 weeks. In vitro experiments, we found that high glucose (HG) could increase the expression of CaSR, α-smooth muscle actin (α-SMA), transforming growth factor-ß1 (TGF-ß1) collagen I/III, matrix metalloproteinase-2 (MMP-2), MMP9, along with cardiac fibroblast migration and proliferation. We further demonstrated that CaSR activation increased intracellular Ca2+ concentration and upregulated the expression of Itch (atrophin-1 interacting protein 4), which resulted in increasing the ubiquitination levels of Smad7 and upregulating the expression of p-Smad2, p-Smad3. However, treatment with Calhex231 clearly inhibited the above-mentioned changes. Collectively these results suggest that Calhex231 could inhibit Itch-ubiquitin proteasome and TGF-ß1/Smads pathways, and then depress the proliferation of cardiac fibroblasts, along with the reduction deposition of collagen, alleviate glucose-induced myocardial fibrosis. Our findings indicate an important new mechanism for myocardial fibrosis, and suggest Calhex231 would be a new therapeutic agent for the treatment of DCM.


Assuntos
Benzamidas/farmacologia , Cicloexilaminas/farmacologia , Cardiomiopatias Diabéticas/patologia , Fibrose/tratamento farmacológico , Miocárdio/patologia , Receptores de Detecção de Cálcio/antagonistas & inibidores , Ubiquitina-Proteína Ligases/metabolismo , Animais , Cálcio/metabolismo , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Colágeno Tipo I/metabolismo , Colágeno Tipo III/metabolismo , Diabetes Mellitus Tipo 1/induzido quimicamente , Diabetes Mellitus Tipo 1/metabolismo , Diabetes Mellitus Tipo 1/patologia , Cardiomiopatias Diabéticas/induzido quimicamente , Cardiomiopatias Diabéticas/metabolismo , Fibroblastos/efeitos dos fármacos , Fibroblastos/metabolismo , Fibrose/metabolismo , Glucose/metabolismo , Coração , Masculino , Metaloproteinase 2 da Matriz/metabolismo , Metaloproteinase 9 da Matriz/metabolismo , Modelos Animais , Miocárdio/metabolismo , Cultura Primária de Células , Complexo de Endopeptidases do Proteassoma/metabolismo , Ratos , Ratos Wistar , Transdução de Sinais , Proteína Smad2/metabolismo , Proteína Smad3/metabolismo , Proteína Smad7/metabolismo , Fator de Crescimento Transformador beta1/metabolismo , Ubiquitinas/metabolismo
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