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1.
Chembiochem ; 23(1): e202100253, 2022 01 05.
Artigo em Inglês | MEDLINE | ID: mdl-34252249

RESUMO

The identification of growth inhibitory compounds with the ability to selectively target the cellular oxygenation state may be of therapeutic interest. Here, a phenotypic screen of a covalent fragment library revealed diverse compounds containing propiolamide warheads with selective toxicity for liver cancer cells in normoxic conditions. Target identification and validation through CETSA and direct pulldown experiments demonstrated that several compounds target glutathione peroxidase 4 (GPX4) and induce ferroptotic cell death. Although being an oxidative cell death mechanism, ferroptosis can be induced also under hypoxic conditions. Prompted by the selective toxicity discovered in the screen, we mapped the oxygen-dependence of several ferroptosis-inducing compounds across three different cell lines. These studies revealed combinations with notable reductions in sensitivity under hypoxic conditions. These observations are mechanistically interesting and may be relevant for the use of ferroptosis-inducers as anti-cancer agents.


Assuntos
Antineoplásicos/farmacologia , Citotoxinas/farmacologia , Inibidores Enzimáticos/farmacologia , Glutationa Peroxidase/antagonistas & inibidores , Oxigênio/farmacologia , Antineoplásicos/química , Apoptose/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Citotoxinas/química , Ensaios de Seleção de Medicamentos Antitumorais , Inibidores Enzimáticos/química , Glutationa Peroxidase/metabolismo , Células Hep G2 , Humanos , Estrutura Molecular , Oxigênio/química
2.
Int J Mol Sci ; 22(14)2021 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-34299253

RESUMO

Pentathiepins are polysulfur-containing compounds that exert antiproliferative and cytotoxic activity in cancer cells, induce oxidative stress and apoptosis, and inhibit glutathione peroxidase (GPx1). This renders them promising candidates for anticancer drug development. However, the biological effects and how they intertwine have not yet been systematically assessed in diverse cancer cell lines. In this study, six novel pentathiepins were synthesized to suit particular requirements such as fluorescent properties or improved water solubility. Structural elucidation by X-ray crystallography was successful for three derivatives. All six underwent extensive biological evaluation in 14 human cancer cell lines. These studies included investigating the inhibition of GPx1 and cell proliferation, cytotoxicity, and the induction of ROS and DNA strand breaks. Furthermore, selected hallmarks of apoptosis and the impact on cell cycle progression were studied. All six pentathiepins exerted high cytotoxic and antiproliferative activity, while five also strongly inhibited GPx1. There is a clear connection between the potential to provoke oxidative stress and damage to DNA in the form of single- and double-strand breaks. Additionally, these studies support apoptosis but not ferroptosis as the mechanism of cell death in some of the cell lines. As the various pentathiepins give rise to different biological responses, modulation of the biological effects depends on the distinct chemical structures fused to the sulfur ring. This may allow for an optimization of the anticancer activity of pentathiepins in the future.


Assuntos
Glutationa Peroxidase/antagonistas & inibidores , Tiepinas/química , Tiepinas/farmacologia , Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Glutationa/metabolismo , Glutationa Peroxidase/metabolismo , Humanos , Estrutura Molecular , Estresse Oxidativo/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo , Relação Estrutura-Atividade , Glutationa Peroxidase GPX1
3.
Sci Rep ; 10(1): 20415, 2020 11 23.
Artigo em Inglês | MEDLINE | ID: mdl-33230173

RESUMO

Catalpol has gained increasing attention for its potential contributions in controlling glycolipid metabolism and diabetic complications, which makes used as a very promising scaffold for seeking new anti-diabetic drug candidates. Acylation derivatives of catalpol crotonate (CCs) were designed as drug ligands of glutathione peroxidase (GSH-Px) based on molecular docking (MD) using Surfex-Docking method. Catalpol hexacrotonate (CC-6) was synthesized using microwave assisted method and characterized by FT-IR, NMR, HPLC and HRMS. The MD results indicate that with the increasing of esterification degree of hydroxyl, the C log P of CCs increased significantly, and the calculated total scores (Total_score) of CCs are all higher than that of catalpol. It shows that CCs maybe served as potential lead compounds for neuroprotective agents. It was found that the maximum Total_score of isomers in one group CCs is often not that the molecule with minimum energy. MD calculations show that there are five hydrogen bonds formed between CC-6 and the surrounding amino acid residues. Molecular dynamics simulation results show that the binding of CC-6 with GSH-Px is stable. CC-6 was screened for SH-SY5Y cells viability by MTT (3-(4, 5-dimethylthiazolyl-2)-2, 5-diphenyltetrazolium bromide) assay, the result indicates CC-6 can effectively reverse SZT induced cells apoptosis with dose-dependent manner, which can indirectly show that CC-6 is a potential neuroprotective agent.


Assuntos
Crotonatos/farmacologia , Glutationa Peroxidase/antagonistas & inibidores , Hipoglicemiantes/farmacologia , Glucosídeos Iridoides/farmacologia , Fármacos Neuroprotetores/farmacologia , Sítios de Ligação , Encefalopatias/tratamento farmacológico , Encefalopatias/enzimologia , Encefalopatias/etiologia , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Crotonatos/síntese química , Complicações do Diabetes/tratamento farmacológico , Complicações do Diabetes/enzimologia , Diabetes Mellitus/tratamento farmacológico , Diabetes Mellitus/enzimologia , Glutationa Peroxidase/química , Glutationa Peroxidase/metabolismo , Humanos , Ligação de Hidrogênio , Hipoglicemiantes/síntese química , Glucosídeos Iridoides/síntese química , Micro-Ondas , Modelos Moleculares , Simulação de Acoplamento Molecular , Simulação de Dinâmica Molecular , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Neurônios/patologia , Fármacos Neuroprotetores/síntese química , Ligação Proteica
4.
Toxicol Ind Health ; 36(11): 844-851, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32909914

RESUMO

Di-2-ethylhexyl phthalate (DEHP) has been widely used as a plasticizer in industry and can affect memory; however, the underlying mechanism remains unclear. In the present study, mouse HT22 cells, an immortalized hippocampal neuronal cell line, was utilized as an in vitro model. We showed that DEHP dramatically inhibited cell viability and increased lactate dehydrogenase (LDH) release from the cells in a dose-dependent manner, suggesting that DEHP could cause cytotoxicity of mouse HT22 cells. The protein levels of cleaved Caspase-8, cleaved Caspase-3, and Bax markedly increased in the DEHP-treated cells, whereas there was a significant decrease in the Bcl-2 protein level, implying that DEHP could induce apoptosis of mouse HT22 cells. DEHP exposure significantly increased the content of malondialdehyde, whereas it markedly decreased the level of glutathione and the activities of glutathione peroxidase and superoxide dismutase, suggesting that DEHP induced oxidative stress of the cells. Compared with the DEHP-treated group, the inhibition of cell viability and the release of LDH were rescued in the N-acetyl-l-cysteine plus DEHP group. Furthermore, inhibition of oxidative stress could rescue the induction of apoptosis by DEHP. Collectively, our results indicated that DEHP could induce apoptosis of mouse HT22 cells via oxidative stress.


Assuntos
Apoptose/efeitos dos fármacos , Dietilexilftalato/toxicidade , Neurônios/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Animais , Caspases/efeitos dos fármacos , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Glutationa Peroxidase/antagonistas & inibidores , Hipocampo/efeitos dos fármacos , L-Lactato Desidrogenase/biossíntese , Camundongos , Proteínas Proto-Oncogênicas c-bcl-2 , Superóxido Dismutase/antagonistas & inibidores
5.
ChemMedChem ; 15(16): 1515-1528, 2020 08 19.
Artigo em Inglês | MEDLINE | ID: mdl-32311219

RESUMO

A novel class of glutathione peroxidase 1 (GPx1) inhibitors, namely tri- and tetracyclic pentathiepins, has been identified that is approximately 15 times more potent than the most active known GPx1 inhibitor, mercaptosuccinic acid. Enzyme kinetic studies with bovine erythrocyte GPx1 indicate that pentathiepins reversibly inhibit oxidation of the substrate glutathione (GSH). Moreover, no inhibition of superoxide dismutase, catalase, thioredoxin reductase or glutathione reductase was observed at concentrations that effectively inhibit GPx1. As well as potent enzyme inhibitory activity, the pentathiepins show strong anticancer activity in various human cancer cell lines, with IC50 values in a low-micromolar range. A representative tetracyclic pentathiepin causes the formation of reactive oxygen species in these cells, the fragmentation of nuclear DNA and induces apoptosis via the intrinsic pathway. Moreover, this pentathiepin leads to a rapid and strong loss of mitochondrial membrane potential in treated cancer cells. On the other hand, evidence for the induction of ferroptosis as a form of cell death was negative. These new findings show that pentathiepins possess interesting biological activities beyond those originally ascribed to these compounds.


Assuntos
Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Inibidores Enzimáticos/farmacologia , Glutationa Peroxidase/antagonistas & inibidores , Compostos Heterocíclicos/farmacologia , Sulfetos/farmacologia , Antineoplásicos/síntese química , Antineoplásicos/química , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Inibidores Enzimáticos/síntese química , Inibidores Enzimáticos/química , Glutationa Peroxidase/metabolismo , Compostos Heterocíclicos/síntese química , Compostos Heterocíclicos/química , Humanos , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Estrutura Molecular , Estresse Oxidativo/efeitos dos fármacos , Relação Estrutura-Atividade , Sulfetos/síntese química , Sulfetos/química , Células Tumorais Cultivadas , Glutationa Peroxidase GPX1
6.
Pharmacol Rep ; 72(4): 992-1001, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31997260

RESUMO

BACKGROUND: Idiopathic pulmonary fibrosis (IPF) is a chronic and fibrotic lung disease of unknown causes. Given the crucial role of oxidative stress in the progression of IPF, antioxidant therapy may be speculated to be an efficient therapeutic approach. Therefore, the present study aimed to evaluate the protective effects of Crocin as a potent, natural antioxidant against Bleomycin-induced PF in male Wistar rats. METHODS: Forty male Wistar rats were randomly divided into four groups. Group 1 received intratracheal saline on day 7 and oral gavage of saline for 28 days. Group 2 received a single dose of Bleomycin on day 7 and oral gavage of saline for 28 days. Groups 3 received a single dose of Bleomycin on day 7, accompanied with oral administration of Crocin for 28 days. Group 4 orally received Crocin for 28 days. Finally, the lungs were removed for measuring the biochemical and histopathological markers. RESULTS: The results showed that Crocin therapy remarkably decreased TNF-α, MDA and NO levels in the lungs of Bleomycin-exposed rats. Furthermore, a significant increase was seen in lung GSH content, catalase, and GPx activities in the Crocin/Bleomycin-treated group as compared with Bleomycin-treated group. However, Crocin could not markedly change the lung index and SOD activity. Histopathological changes, fibrosis and hydroxyproline content of lungs also significantly decreased by Crocin therapy in the Crocin/Bleomycin-treated group. CONCLUSION: In sum, Crocin therapy could modulate biochemical and histological changes induced by Bleomycin; therefore, it might be considered as an effective therapeutic approach against IPF.


Assuntos
Antioxidantes/uso terapêutico , Bleomicina/toxicidade , Carotenoides/uso terapêutico , Fibrose Pulmonar/induzido quimicamente , Fibrose Pulmonar/prevenção & controle , Animais , Antibióticos Antineoplásicos/toxicidade , Antioxidantes/farmacologia , Carotenoides/farmacologia , Glutationa Peroxidase/antagonistas & inibidores , Glutationa Peroxidase/metabolismo , Masculino , Fibrose Pulmonar/metabolismo , Ratos , Ratos Wistar , Superóxido Dismutase/antagonistas & inibidores , Superóxido Dismutase/metabolismo
7.
Biol Trace Elem Res ; 195(1): 135-141, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-31309445

RESUMO

Despite the fact that iron represents a crucial element for the catalysis of many metabolic reactions, its accumulation in the cell leads to the production of reactive oxygen species (ROS), provoking pathological conditions such as cancer, cardiovascular diseases, diabetes, neurodegenerative diseases, and fertility. Thus, ROS are neutralized by the enzymatic antioxidant system for the purpose of protecting cells against any damage. Iron is a potential risk factor for male fertility. However, the mechanism of action of iron on the testicular antioxidant system at the gene and protein levels is not fully understood. Thus, the purpose of the current research was to ensure a better understanding of how the long-term iron treatment influences both gene expression and enzyme activities of the testicular antioxidant system in rat testis. The data of our study showed that a significant dose-dependent increase occurred in the iron level in rat testis. A reduction occurred in reduced glutathione (GSH) levels, which represent a marker of oxidative stress, along with long-term iron overload. The expression and activity of glucose 6-phosphate dehydrogenase (G6pd), glutathione reductase (Gr), glutathione peroxidase (Gpx), and glutathione S-transferases (Gst) were significantly affected by the presence of iron. The findings of the current research demonstrate that the long-term toxic dietary iron overload influences the gene expression and enzyme activity of the testicular antioxidant defense system, but the actual effect occurs at the protein level. This may modify the sperm function and dysfunction of the male reproductive system.


Assuntos
Antioxidantes/metabolismo , Ferro da Dieta/farmacologia , Testículo/efeitos dos fármacos , Administração Oral , Animais , Relação Dose-Resposta a Droga , Glucosefosfato Desidrogenase/antagonistas & inibidores , Glucosefosfato Desidrogenase/genética , Glucosefosfato Desidrogenase/metabolismo , Glutationa/antagonistas & inibidores , Glutationa/metabolismo , Glutationa Peroxidase/antagonistas & inibidores , Glutationa Peroxidase/genética , Glutationa Peroxidase/metabolismo , Glutationa Redutase/antagonistas & inibidores , Glutationa Redutase/genética , Glutationa Redutase/metabolismo , Glutationa Transferase/antagonistas & inibidores , Glutationa Transferase/genética , Glutationa Transferase/metabolismo , Ferro da Dieta/administração & dosagem , Masculino , Estresse Oxidativo/efeitos dos fármacos , Ratos , Ratos Sprague-Dawley , Testículo/metabolismo
8.
Biochem Biophys Res Commun ; 518(3): 590-597, 2019 10 20.
Artigo em Inglês | MEDLINE | ID: mdl-31445705

RESUMO

RSL3 is a type of small molecular compound which can inactivate glutathione peroxidase 4 (GPX4) and induce ferroptosis, but its role in glioma cell death remains unclear. In this study, we found RSL3 inhibited the viabilities of glioma cells and induced glioma cell death in a dose-dependent manner. In vitro studies revealed that RSL3-induced cell death was accompanied with the changes of autophagy-associated protein levels and was alleviated by pretreatment of 3-Methyladenine, bafilomycin A1 and knockdown of ATG5 with siRNA. The ATP and pyruvate content as well as the protein levels of HKII, PFKP, PKM2 were decreased in cells treated by RSL3, indicating that RSL3 induced glycolysis dysfunction in glioma cells. Moreover, supplement of exterior sodium pyruvate, which was a final product of glycolysis, not only inhibited the changes of autophagy-associated protein levels caused by RSL3, but also prevented RSL3-induced cell death. In vivo data suggested that the inhibitory effect of RSL3 on the growth of glioma cells was associated with glycolysis dysfunction and autophagy activation. Taken together, RSL3 induced autophagic cell death in glioma cells via causing glycolysis dysfunction.


Assuntos
Antineoplásicos/farmacologia , Morte Celular Autofágica/efeitos dos fármacos , Carbolinas/farmacologia , Glioma/tratamento farmacológico , Glicólise/efeitos dos fármacos , Animais , Antineoplásicos/uso terapêutico , Carbolinas/uso terapêutico , Linhagem Celular Tumoral , Inibidores Enzimáticos/farmacologia , Glioma/metabolismo , Glioma/patologia , Glutationa Peroxidase/antagonistas & inibidores , Glutationa Peroxidase/metabolismo , Humanos , Camundongos Endogâmicos BALB C , Camundongos Nus , Ratos
9.
Life Sci ; 231: 116572, 2019 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-31207309

RESUMO

OBJECTIVES: The aim of this study was to investigate whether some of the cephalosporin group antibiotics have inhibition effects on GR and GST enzymes with important functions in the metabolic pathway. METHODS: In this study, some selected cephalosporin group antibiotics on GST and GR enzyme was carried out using 96 rats. 16 groups (16 × 6) were created from these rats, divided to another 4 groups (4 × 24). The resulting groups were named as sham groups, cefazolin groups, cefuroxime groups and cefoperazone groups, respectively. The antibiotics used were injected to cefazolin, cefuroxime and cefoperazone groups. The inhibition effects of the antibiotics were measured in the different time intervals (1st, 3th, 5th, 7th). The statistical investigation of the results was performed using the SPSS software program. RESULTS: Results revealed the complex effects of the tested substances on GR and GST activity at different time intervals and in different tissues (p < 0.05). This indicated that the tested substances could be exposed to different interactions in vivo. CONCLUSION: The tested antibiotics showed some significant inhibition effects on the GST and GR enzyme activity in some tissues of brain, eye and muscle. The interaction of enzyme - the drug is a key factor to highlight the toxicological mechanism. For this reason, the results obtained from in vivo experiments are crucial to explane the physiological properties of the enzymes.


Assuntos
Cefalosporinas/farmacologia , Glutationa Redutase/antagonistas & inibidores , Glutationa Transferase/antagonistas & inibidores , Animais , Antibacterianos/farmacologia , Cefazolina/farmacologia , Cefoperazona/farmacologia , Cefuroxima/farmacologia , Inibidores Enzimáticos/farmacologia , Glutationa/metabolismo , Glutationa Peroxidase/antagonistas & inibidores , Glutationa Peroxidase/metabolismo , Glutationa Redutase/metabolismo , Glutationa Transferase/metabolismo , Ratos
10.
Nat Cell Biol ; 21(5): 579-591, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30962574

RESUMO

It is well established that ferroptosis is primarily controlled by glutathione peroxidase 4 (GPX4). Surprisingly, we observed that p53 activation modulates ferroptotic responses without apparent effects on GPX4 function. Instead, ALOX12 inactivation diminishes p53-mediated ferroptosis induced by reactive oxygen species stress and abrogates p53-dependent inhibition of tumour growth in xenograft models, suggesting that ALOX12 is critical for p53-mediated ferroptosis. The ALOX12 gene resides on human chromosome 17p13.1, a hotspot of monoallelic deletion in human cancers. Loss of one Alox12 allele is sufficient to accelerate tumorigenesis in Eµ-Myc lymphoma models. Moreover, ALOX12 missense mutations from human cancers abrogate its ability to oxygenate polyunsaturated fatty acids and to induce p53-mediated ferroptosis. Notably, ALOX12 is dispensable for ferroptosis induced by erastin or GPX4 inhibitors; conversely, ACSL4 is required for ferroptosis upon GPX4 inhibition but dispensable for p53-mediated ferroptosis. Thus, our study identifies an ALOX12-mediated, ACSL4-independent ferroptosis pathway that is critical for p53-dependent tumour suppression.


Assuntos
Araquidonato 12-Lipoxigenase/genética , Carcinogênese/genética , Glutationa Peroxidase/genética , Proteína Supressora de Tumor p53/genética , Animais , Apoptose/genética , Linhagem Celular Tumoral , Modelos Animais de Doenças , Glutationa Peroxidase/antagonistas & inibidores , Humanos , Peroxidação de Lipídeos/genética , Linfoma/genética , Linfoma/patologia , Camundongos , Mutação de Sentido Incorreto/genética , Fosfolipídeo Hidroperóxido Glutationa Peroxidase , Espécies Reativas de Oxigênio , Ensaios Antitumorais Modelo de Xenoenxerto
11.
Free Radic Biol Med ; 129: 454-462, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30339884

RESUMO

Glutathione peroxidase 4 (GPX4) is a regulator of ferroptosis (iron-dependent, non-apoptotic cell death); its inhibition can render therapy-resistant cancer cells susceptible to ferroptosis. However, some cancer cells develop mechanisms protective against ferroptosis; understanding these mechanisms could help overcome chemoresistance. In this study, we investigated the molecular mechanisms underlying resistance to ferroptosis induced by GPX4 inhibition in head and neck cancer (HNC). The effects of two GPX4 inhibitors, (1S, 3R)-RSL3 and ML-162, and of trigonelline were tested in HNC cell lines, including cisplatin-resistant (HN3R) and acquired RSL3-resistant (HN3-rslR) cells. The effects of the inhibitors and trigonelline, as well as of inhibition of the p62, Keap1, or Nrf2 genes, were assessed by cell viability, cell death, lipid ROS production, and protein expression, and in mouse tumor xenograft models. Treatment with RSL3 or ML-162 induced the ferroptosis of HNC cells to varying degrees. RSL3 or ML-162 treatment increased the expression of p62 and Nrf2 in chemoresistant HN3R and HN3-rslR cells, inactivated Keap1, and increased expression of the phospho-PERK-ATF4-SESN2 pathway. Transcriptional activation of Nrf2 was associated with resistance to ferroptosis. Overexpression of Nrf2 by inhibiting Keap1 or Nrf2 gene transfection rendered chemosensitive HN3 cells resistant to RSL3. However, Nrf2 inhibition or p62 silencing sensitized HN3R cells to RSL3. Trigonelline sensitized chemoresistant HNC cells to RSL3 treatment in a mouse model transplanted with HN3R. Thus, activation of the Nrf2-ARE pathway contributed to the resistance of HNC cells to GPX4 inhibition, and inhibition of this pathway reversed the resistance to ferroptosis in HNC.


Assuntos
Antineoplásicos/farmacologia , Regulação Neoplásica da Expressão Gênica , Glutationa Peroxidase/genética , Neoplasias de Cabeça e Pescoço/genética , Ferro/metabolismo , Fator 2 Relacionado a NF-E2/genética , Fator 4 Ativador da Transcrição/genética , Fator 4 Ativador da Transcrição/metabolismo , Alcaloides/farmacologia , Animais , Carbolinas/farmacologia , Morte Celular/efeitos dos fármacos , Morte Celular/genética , Linhagem Celular Tumoral , Resistencia a Medicamentos Antineoplásicos , Inibidores Enzimáticos/farmacologia , Fibroblastos/efeitos dos fármacos , Fibroblastos/metabolismo , Fibroblastos/patologia , Glutationa Peroxidase/antagonistas & inibidores , Glutationa Peroxidase/metabolismo , Neoplasias de Cabeça e Pescoço/tratamento farmacológico , Neoplasias de Cabeça e Pescoço/metabolismo , Neoplasias de Cabeça e Pescoço/patologia , Humanos , Proteína 1 Associada a ECH Semelhante a Kelch/genética , Proteína 1 Associada a ECH Semelhante a Kelch/metabolismo , Queratinócitos/efeitos dos fármacos , Queratinócitos/metabolismo , Queratinócitos/patologia , Camundongos , Camundongos Nus , Fator 2 Relacionado a NF-E2/antagonistas & inibidores , Fator 2 Relacionado a NF-E2/metabolismo , Proteínas Nucleares/genética , Proteínas Nucleares/metabolismo , Fosfolipídeo Hidroperóxido Glutationa Peroxidase , Espécies Reativas de Oxigênio/metabolismo , Proteína Sequestossoma-1/genética , Proteína Sequestossoma-1/metabolismo , Transdução de Sinais , Ensaios Antitumorais Modelo de Xenoenxerto , eIF-2 Quinase/genética , eIF-2 Quinase/metabolismo
12.
J Food Sci ; 83(5): 1463-1469, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29693723

RESUMO

The content of several phenolic acids and flavonoids in aqueous extract (AE) and ethanol extract (EE) of daylily flower (Hemerocallis fulva L.) was analyzed. The effects of AE or EE at 0.5%, 1%, or 2% in HUVE cells against high glucose-induced cell death, oxidative, and inflammatory damage were examined. Results showed that seven phenolic acids and seven flavonoids could be detected in AE or EE, in the range of 29 to 205 and 41 to 273 mg/100 g, respectively. Compared with the control groups, high glucose raised the activity of caspase-3 and caspase-8; suppressed Bcl-2 mRNA expression and increased Bax mRNA expression; and induced HUVE cells apoptosis. The pretreatments from AE or EE at 1% or 2% reduced caspase-3 activity and Bax mRNA expression, and enhanced cell viability. High glucose decreased glutathione content; stimulated the production of reactive oxygen species, interleukin-6, tumor necrosis factor-alpha, and prostaglandin E2 ; raised the activity of cyclooxygenase-2 and nuclear factor kappa B p50/65 binding; and reduced the activity of glutathione peroxidase, glutathione reductase, and catalase in HUVE cells. AE pretreatments at 1% and 2% reversed these changes. These novel findings suggested that daylily flower was rich in phytochemicals, and could be viewed as a potent functional food against diabetes.


Assuntos
Flores/química , Hemerocallis/química , Extratos Vegetais/farmacologia , Substâncias Protetoras/farmacologia , Antioxidantes/análise , Antioxidantes/farmacologia , Apoptose/efeitos dos fármacos , Caspase 3/metabolismo , Caspase 8/metabolismo , Catalase/antagonistas & inibidores , Catalase/metabolismo , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Ciclo-Oxigenase 2/metabolismo , Dinoprostona/metabolismo , Flavonoides/análise , Flavonoides/farmacologia , Glucose/efeitos adversos , Glutationa Peroxidase/antagonistas & inibidores , Glutationa Peroxidase/metabolismo , Glutationa Redutase/antagonistas & inibidores , Glutationa Redutase/metabolismo , Células Endoteliais da Veia Umbilical Humana/efeitos dos fármacos , Humanos , Interleucina-6/metabolismo , NF-kappa B/metabolismo , Extratos Vegetais/análise , Substâncias Protetoras/análise , Espécies Reativas de Oxigênio/metabolismo , Fator de Necrose Tumoral alfa/metabolismo
14.
Comp Biochem Physiol C Toxicol Pharmacol ; 206-207: 17-22, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29471151

RESUMO

The herbicide atrazine (ATZ) is used worldwide in the control of annual grasses and broad-leaved weeds. The present study evaluated sperm quality parameters in zebrafish Danio rerio after 11-day exposure to nominal ATZ concentrations of 2, 10, and 100 µg L-1. All ATZ concentrations caused a decrease in motility, mitochondrial functionality, and membrane integrity, as measured using conventional microscopy or fluorescence microscopy with specific probes. The DNA integrity of sperm was not affected. The levels of expression of genes related to spermatogenesis, antioxidant defenses, and DNA repair were also investigated using RT-qPCR. The ATZ caused transcriptional repression of the spermatogenesis-related genes SRD5A2 and CFTR, the antioxidant defense genes SOD2 and GPX4B, and the DNA repair gene XPC. This is the first study to show that environmentally relevant concentrations of ATZ significantly affect the sperm quality in fish, possibly resulting in reduced fertility rates. In addition, we showed that the repression of genes related to spermatogenesis and cellular defense could be part of the mechanisms involved in the ATZ toxicity in the testes of male fish.


Assuntos
Atrazina/toxicidade , Regulação da Expressão Gênica no Desenvolvimento/efeitos dos fármacos , Herbicidas/toxicidade , Espermatogênese/efeitos dos fármacos , Testículo/efeitos dos fármacos , Poluentes Químicos da Água/toxicidade , Peixe-Zebra/fisiologia , 3-Oxo-5-alfa-Esteroide 4-Desidrogenase/química , 3-Oxo-5-alfa-Esteroide 4-Desidrogenase/genética , 3-Oxo-5-alfa-Esteroide 4-Desidrogenase/metabolismo , Animais , Proteínas de Ciclo Celular , Regulador de Condutância Transmembrana em Fibrose Cística/antagonistas & inibidores , Regulador de Condutância Transmembrana em Fibrose Cística/genética , Regulador de Condutância Transmembrana em Fibrose Cística/metabolismo , Glutationa Peroxidase/antagonistas & inibidores , Glutationa Peroxidase/genética , Glutationa Peroxidase/metabolismo , Masculino , Proteínas de Membrana/antagonistas & inibidores , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/enzimologia , Mitocôndrias/metabolismo , Membranas Mitocondriais/efeitos dos fármacos , Membranas Mitocondriais/enzimologia , Membranas Mitocondriais/metabolismo , Concentração Osmolar , Fosfolipídeo Hidroperóxido Glutationa Peroxidase , Distribuição Aleatória , Proteínas de Saccharomyces cerevisiae , Motilidade dos Espermatozoides/efeitos dos fármacos , Superóxido Dismutase/antagonistas & inibidores , Superóxido Dismutase/genética , Superóxido Dismutase/metabolismo , Testículo/citologia , Testículo/metabolismo , Xeroderma Pigmentoso/genética , Xeroderma Pigmentoso/metabolismo , Proteínas de Peixe-Zebra/antagonistas & inibidores , Proteínas de Peixe-Zebra/genética , Proteínas de Peixe-Zebra/metabolismo
15.
Trends Cell Biol ; 28(2): 77-78, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-29223642

RESUMO

Tumor progression and resistance to treatment are often accompanied by the polarization of malignant cells towards a mesenchymal or poorly differentiated state. Such a transition generates an accrued vulnerability to the induction of ferroptosis, potentially paving the way to novel therapeutic strategies for targeting residual disease in patients with cancer.


Assuntos
Antineoplásicos/metabolismo , Apoptose/fisiologia , Resistencia a Medicamentos Antineoplásicos/fisiologia , Ferro/metabolismo , Neoplasias/metabolismo , Animais , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Apoptose/efeitos dos fármacos , Morte Celular/efeitos dos fármacos , Morte Celular/fisiologia , Diferenciação Celular/efeitos dos fármacos , Diferenciação Celular/fisiologia , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Glutationa Peroxidase/antagonistas & inibidores , Glutationa Peroxidase/metabolismo , Humanos , Neoplasias/tratamento farmacológico , Neoplasias/patologia , Fosfolipídeo Hidroperóxido Glutationa Peroxidase
16.
J Inorg Biochem ; 178: 94-105, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-29125948

RESUMO

Here we present the preparation of 14 pairs of cis- and trans-diammine monochlorido platinum(II) complexes, coordinated to heterocycles (i.e., imidazole, 2-methylimidazole and pyrazole) and linked to various acylhydrazones, which were designed as potential inhibitors of the selenium-dependent enzymes glutathione peroxidase 1 (GPx-1) and thioredoxin reductase 1 (TrxR-1). However, no inhibition of bovine GPx-1 and only weak inhibition of murine TrxR-1 was observed in in vitro assays. Nonetheless, the cis configured diammine monochlorido Pt(II) complexes exhibited cytotoxic and apoptotic properties on various human cancer cell lines, whereas the trans configured complexes generally showed weaker potency with a few exceptions. On the other hand, the trans complexes were generally more likely to lack cross-resistance to cisplatin than the cis analogues. Platinum was found bound to the nuclear DNA of cancer cells treated with representative Pt complexes, suggesting that DNA might be a possible target. Thus, detailed in vitro binding experiments with DNA were conducted. Interactions of the compounds with calf thymus DNA were investigated, including Pt binding kinetics, circular dichroism (CD) spectral changes, changes in DNA melting temperatures, unwinding of supercoiled plasmids and ethidium bromide displacement in DNA. The CD results indicate that the most active cis configured pyrazole-derived complex causes unique structural changes in the DNA compared to the other complexes as well as to those caused by cisplatin, suggesting a denaturation of the DNA structure. This may be important for the antiproliferative activity of this compound in the cancer cells.


Assuntos
Ácido Aspártico/análogos & derivados , Condroitina/análogos & derivados , DNA/efeitos dos fármacos , Glutationa Peroxidase/antagonistas & inibidores , Compostos Organoplatínicos/síntese química , Platina/farmacologia , Selênio/farmacologia , Animais , Ácido Aspártico/química , Ácido Aspártico/farmacologia , Bovinos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Condroitina/química , Condroitina/farmacologia , DNA/química , Ativação Enzimática/efeitos dos fármacos , Enzimas/metabolismo , Concentração Inibidora 50 , Camundongos , Estrutura Molecular , Compostos Organoplatínicos/química , Compostos Organoplatínicos/farmacologia , Oxirredução , Platina/química , Platina/toxicidade , Selênio/química , Selênio/toxicidade
17.
Antioxid Redox Signal ; 29(1): 61-74, 2018 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-28462584

RESUMO

SIGNIFICANCE: Iron-dependent lipid peroxidation is a complex oxidative process where phospholipid hydroperoxides (PLOOH) are produced in membranes and finally transformed into a series of decomposition products, some of which are endowed with biological activity. It is specifically prevented by glutathione peroxidase 4 (GPx4), the selenoenzyme that reduces PLOOH by glutathione (GSH). PLOOH is both a product and the major initiator of peroxidative chain reactions, as well as an activator of lipoxygenases. α-Tocopherol both specifically breaks peroxidative chain propagation and inhibits lipoxygenases. Thus, GPx4, GSH, and α-tocopherol are integrated in a concerted anti-peroxidant mechanism. Recent Advances: Ferroptosis has been recently identified as a cell death subroutine that is specifically activated by missing GPx4 activity and inhibited by iron chelation or α-tocopherol supplementation. Ferroptosis induction may underlie spontaneous human diseases, such as major neurodegeneration and neuroinflammation, causing an excessive cell death. The basic mechanism of ferroptosis, therefore, fits the features of activation of lipid peroxidation. CRITICAL ISSUES: Still lacking are convincing proofs that lipoxygenases are involved in ferroptosis. Also, unknown are the molecules eventually killing cells and the mechanisms underlying the drop of the cellular anti-peroxidant capacity. FUTURE DIRECTIONS: Molecular events and mechanisms of ferroptosis to be unraveled and validated on animal models are GPx4 inactivation, role of GSH concentration, increased iron availability, and membrane structure and composition. This is expected to drive drug discovery that is aimed at halting cell death in degenerative diseases or boosting it in cancer cells. Antioxid. Redox Signal. 29, 61-74.


Assuntos
Morte Celular , Glutationa Peroxidase/metabolismo , Peroxidação de Lipídeos , Animais , Morte Celular/efeitos dos fármacos , Glutationa Peroxidase/antagonistas & inibidores , Humanos , Quelantes de Ferro/farmacologia , Peroxidação de Lipídeos/efeitos dos fármacos , Fosfolipídeo Hidroperóxido Glutationa Peroxidase , alfa-Tocoferol/farmacologia
18.
Nature ; 551(7679): 247-250, 2017 11 09.
Artigo em Inglês | MEDLINE | ID: mdl-29088702

RESUMO

Acquired drug resistance prevents cancer therapies from achieving stable and complete responses. Emerging evidence implicates a key role for non-mutational drug resistance mechanisms underlying the survival of residual cancer 'persister' cells. The persister cell pool constitutes a reservoir from which drug-resistant tumours may emerge. Targeting persister cells therefore presents a therapeutic opportunity to impede tumour relapse. We previously found that cancer cells in a high mesenchymal therapy-resistant cell state are dependent on the lipid hydroperoxidase GPX4 for survival. Here we show that a similar therapy-resistant cell state underlies the behaviour of persister cells derived from a wide range of cancers and drug treatments. Consequently, we demonstrate that persister cells acquire a dependency on GPX4. Loss of GPX4 function results in selective persister cell ferroptotic death in vitro and prevents tumour relapse in mice. These findings suggest that targeting of GPX4 may represent a therapeutic strategy to prevent acquired drug resistance.


Assuntos
Apoptose/efeitos dos fármacos , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Glutationa Peroxidase/antagonistas & inibidores , Neoplasias/tratamento farmacológico , Neoplasias/patologia , Animais , Antioxidantes/metabolismo , Avaliação Pré-Clínica de Medicamentos , Feminino , Humanos , Ferro/metabolismo , Masculino , Mesoderma/efeitos dos fármacos , Mesoderma/enzimologia , Mesoderma/patologia , Camundongos , Terapia de Alvo Molecular , Neoplasias/enzimologia , Fosfolipídeo Hidroperóxido Glutationa Peroxidase , Recidiva , Ensaios Antitumorais Modelo de Xenoenxerto
19.
PLoS One ; 12(10): e0185943, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29016640

RESUMO

Virally mediated RNA interference (RNAi) to knock down injury-induced genes could improve functional outcome after traumatic brain injury (TBI); however, little is known about the consequences of gene knockdown on downstream cell signaling pathways and how RNAi influences neurodegeneration and behavior. Here, we assessed the effects of adeno-associated virus (AAV) siRNA vectors that target two genes with opposing roles in TBI pathogenesis: the allegedly detrimental neuronal nitric oxide synthase (nNOS) and the potentially protective glutathione peroxidase 1 (GPx-1). In rat hippocampal progenitor cells, three siRNAs that target different regions of each gene (nNOS, GPx-1) effectively knocked down gene expression. However, in vivo, in our rat model of fluid percussion brain injury, the consequences of AAV-siRNA were variable. One nNOS siRNA vector significantly reduced the number of degenerating hippocampal neurons and showed a tendency to improve working memory. GPx-1 siRNA treatment did not alter TBI-induced neurodegeneration or working memory deficits. Nevertheless, microarray analysis of laser captured, virus-infected neurons showed that knockdown of nNOS or GPx-1 was specific and had broad effects on downstream genes. Since nNOS knockdown only modestly ameliorated TBI-induced working memory deficits, despite widespread genomic changes, manipulating expression levels of single genes may not be sufficient to alter functional outcome after TBI.


Assuntos
Lesões Encefálicas Traumáticas/genética , Dependovirus/genética , Glutationa Peroxidase/genética , Transtornos da Memória/genética , Óxido Nítrico Sintase Tipo I/genética , Interferência de RNA , Animais , Lesões Encefálicas Traumáticas/metabolismo , Lesões Encefálicas Traumáticas/fisiopatologia , Dependovirus/metabolismo , Perfilação da Expressão Gênica , Técnicas de Silenciamento de Genes , Glutationa Peroxidase/antagonistas & inibidores , Glutationa Peroxidase/metabolismo , Hipocampo/metabolismo , Hipocampo/fisiopatologia , Microdissecção e Captura a Laser , Masculino , Aprendizagem em Labirinto , Transtornos da Memória/metabolismo , Transtornos da Memória/fisiopatologia , Memória de Curto Prazo/fisiologia , Redes e Vias Metabólicas/genética , Análise em Microsséries , Células-Tronco Neurais/citologia , Células-Tronco Neurais/metabolismo , Neurônios/metabolismo , Neurônios/patologia , Óxido Nítrico Sintase Tipo I/antagonistas & inibidores , Óxido Nítrico Sintase Tipo I/metabolismo , RNA Interferente Pequeno/genética , RNA Interferente Pequeno/metabolismo , Ratos , Ratos Sprague-Dawley , Transdução de Sinais , Glutationa Peroxidase GPX1
20.
J Cell Biol ; 216(12): 4287-4297, 2017 12 04.
Artigo em Inglês | MEDLINE | ID: mdl-28972104

RESUMO

Increases in lipid peroxidation can cause ferroptosis, a form of cell death triggered by inhibition of glutathione peroxidase 4 (GPX4), which catalyzes the reduction of lipid peroxides and is a target of ferroptosis inducers, such as erastin. The α6ß4 integrin protects adherent epithelial and carcinoma cells from ferroptosis induced by erastin. In addition, extracellular matrix (ECM) detachment is a physiologic trigger of ferroptosis, which is evaded by α6ß4. The mechanism that enables α6ß4 to evade ferroptosis involves its ability to protect changes in membrane lipids that are proferroptotic. Specifically, α6ß4-mediated activation of Src and STAT3 suppresses expression of ACSL4, an enzyme that enriches membranes with long polyunsaturated fatty acids and is required for ferroptosis. Adherent cells lacking α6ß4 require an inducer, such as erastin, to undergo ferroptosis because they sustain GPX4 expression, despite their increase in ACSL4. In contrast, ECM detachment of cells lacking α6ß4 is sufficient to trigger ferroptosis because GPX4 is suppressed. This causal link between α6ß4 and ferroptosis has implications for cancer biology and therapy.


Assuntos
Coenzima A Ligases/genética , Células Epiteliais/metabolismo , Regulação Neoplásica da Expressão Gênica , Glutationa Peroxidase/genética , Integrina alfa6beta4/genética , Quinases da Família src/genética , Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Apoptose/genética , Adesão Celular/efeitos dos fármacos , Linhagem Celular , Linhagem Celular Tumoral , Coenzima A Ligases/metabolismo , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/patologia , Matriz Extracelular/efeitos dos fármacos , Matriz Extracelular/metabolismo , Matriz Extracelular/ultraestrutura , Feminino , Glutationa Peroxidase/antagonistas & inibidores , Glutationa Peroxidase/metabolismo , Humanos , Integrina alfa6beta4/metabolismo , Ferro/metabolismo , Peroxidação de Lipídeos/efeitos dos fármacos , Fosfolipídeo Hidroperóxido Glutationa Peroxidase , Piperazinas/farmacologia , Fator de Transcrição STAT3/genética , Fator de Transcrição STAT3/metabolismo , Transdução de Sinais , Quinases da Família src/metabolismo
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