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1.
Biofactors ; 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38488303

RESUMO

Currently, a diagnosis with KRAS mutant pancreatic ductal adenocarcinoma (PDAC) means a death warrant, so finding efficient therapeutic options is a pressing issue. Here, we presented that pharmacologic ascorbate, chloroquine and resveratrol co-treatment exerted a synergistic cytotoxic effect on PDAC cell lines. The observed synergistic cytotoxicity was a general feature in all investigated cancer cell lines independent of the KRAS mutational status and seems to be independent of the autophagy inhibitory effect of chloroquine. Furthermore, it seems that apoptosis and necroptosis are also not likely to play any role in the cytotoxicity of chloroquine. Both pharmacologic ascorbate and resveratrol caused double-strand DNA breaks accompanied by cell cycle arrest. It seems resveratrol-induced cytotoxicity is independent of reactive oxygen species (ROS) generation and accompanied by a significant elevation of caspase-3/7 activity, while pharmacologic ascorbate-induced cytotoxicity shows strong ROS dependence but proved to be caspase-independent. Our results are particularly important since ascorbate and resveratrol are natural compounds without significant harmful effects on normal cells, and chloroquine is a known antimalarial drug that can easily be repurposed.

2.
Int J Mol Sci ; 23(19)2022 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-36232313

RESUMO

Ferroptosis represents a typical process that has dual functions in cell fate decisions since the reduction and/or inhibition of ferroptosis is desirable for the therapies of diseases such as neurological disorders, localized ischemia-reperfusion, kidney injury, and hematological diseases, while the enhanced ferroptosis of cancer cells may benefit patients with cancer. The JNK pathway also has a real dual function in the fate of cells. Multiple factors suggest a potential link between the ferroptotic and JNK pathways; (i) both processes are ROS mediated; (ii) both can be inhibited by lipid peroxide scavengers; (iii) RAS mutations may play a role in the initiation of both pathways. We aimed to investigate the possible link between ferroptosis and the JNK pathway. Interestingly, JNK inhibitor co-treatment could enhance the cancer cytotoxic effect of the ferroptosis inducers in NRAS and KRAS mutation-harboring cells (HT-1080 and MIA PaCa-2). Since cancer's cytotoxic effect from the JNK inhibitors could only be suspended by the ferroptosis inhibitors, and that sole JNK-inhibitor treatment did not affect cell viability, it seems that the JNK inhibitors "just" amplify the effect of the ferroptosis inducers. This cancer cell death amplifying effect of the JNK inhibitors could not be observed in other oxidative stress-driven cell deaths. Hence, it seems it is specific to ferroptosis. Finally, our results suggest that GSH content/depletion could be an important candidate for switching the anti-cancer effect of JNK inhibitors.


Assuntos
Antineoplásicos , Ferroptose , Neoplasias , Antineoplásicos/farmacologia , Humanos , Peróxidos Lipídicos , Sistema de Sinalização das MAP Quinases , Neoplasias/metabolismo , Proteínas Proto-Oncogênicas p21(ras)/genética , Proteínas Proto-Oncogênicas p21(ras)/metabolismo , Espécies Reativas de Oxigênio/metabolismo
3.
Int J Mol Sci ; 23(9)2022 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-35563576

RESUMO

An element, iron, a process, the generation of reactive oxygen species (ROS), and a molecule, ascorbate, were chosen in our study to show their dual functions and their role in cell fate decision. Iron is a critical component of numerous proteins involved in metabolism and detoxification. On the other hand, excessive amounts of free iron in the presence of oxygen can promote the production of potentially toxic ROS. They can result in persistent oxidative stress, which in turn can lead to damage and cell death. At the same time, ROS-at strictly regulated levels-are essential to maintaining the redox homeostasis, and they are engaged in many cellular signaling pathways, so their total elimination is not expedient. Ascorbate establishes a special link between ROS generation/elimination and cell death. At low concentrations, it behaves as an excellent antioxidant and has an important role in ROS elimination. However, at high concentrations, in the presence of transition metals such as iron, it drives the generation of ROS. In the term of the dual function of these molecules and oxidative stress, ascorbate/ROS-driven cell deaths are not necessarily harmful processes-they can be live-savers too.


Assuntos
Antioxidantes , Estresse Oxidativo , Antioxidantes/metabolismo , Ferro/metabolismo , Oxirredução , Espécies Reativas de Oxigênio/metabolismo
4.
Life (Basel) ; 11(8)2021 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-34440600

RESUMO

Investigation of drug-induced liver injuries requires appropriate in vivo and in vitro toxicological model systems. In our study, an attempt was made to compare the hepatocarcinoma HepG2 and the stem cell-derived HepaRG cell lines both in two- and three-dimensional culture conditions to find the most suitable model. Comparison of the liver-specific characteristics of these models was performed via the extent and mechanism of acetaminophen (APAP)-induced hepatotoxicity. Investigating the detailed mechanism of APAP-induced hepatotoxicity, different specific cell death inhibitors were used: the pan-caspase inhibitor zVAD-fmk and dabrafenib significantly protected both cell lines from APAP-induced cell death. However, the known specific inhibitors of necroptosis (necrostatin-1 and MDIVI) were only effective in differentiated HepaRG, which suggest a differential execution of activated pathways in the two models. By applying 3D culture methods, CYP2E1 mRNA levels could be elevated, but we failed to achieve a significant increase in hepatocyte function; hence, the 3D cultivation especially in APAP toxicity studies is not necessarily worth the complicated maintenance. Based on our findings, the hepatocyte functions of HepaRG may stand between the properties of HepG2 cells and primary hepatocytes (PHHs). However, it should be noted that in contrast to PHHs having many limitations, HepaRG cells are relatively immortal, having a stable phenotype and CYP450 expression.

5.
Biomolecules ; 11(5)2021 04 28.
Artigo em Inglês | MEDLINE | ID: mdl-33925206

RESUMO

The Warburg effect has been considered a potential therapeutic target to fight against cancer progression. In KRAS mutant cells, PKM2 (pyruvate kinase isozyme M2) is hyper-activated, and it induces GLUT1 expression; therefore, KRAS has been closely involved in the initiation of Warburg metabolism. Although mTOR (mammalian target of rapamycin), a well-known inhibitor of autophagy-dependent survival in physiological conditions, is also activated in KRAS mutants, many recent studies have revealed that autophagy becomes hyper-active in KRAS mutant cancer cells. In the present study, a mathematical model was built containing the main elements of the regulatory network in KRAS mutant cancer cells to explore the further possible therapeutic strategies. Our dynamical analysis suggests that the downregulation of KRAS, mTOR and autophagy are crucial in anti-cancer therapy. PKM2 has been assumed to be the key switch in the stress response mechanism. We predicted that the addition of both pharmacologic ascorbate and chloroquine is able to block both KRAS and mTOR pathways: in this case, no GLUT1 expression is observed, meanwhile autophagy, essential for KRAS mutant cancer cells, is blocked. Corresponding to our system biological analysis, this combined pharmacologic ascorbate and chloroquine treatment in KRAS mutant cancers might be a therapeutic approach in anti-cancer therapies.


Assuntos
Cloroquina/farmacologia , Neoplasias/metabolismo , Proteínas Proto-Oncogênicas p21(ras)/genética , Antineoplásicos/farmacologia , Autofagia/efeitos dos fármacos , Modelos Teóricos , Neoplasias/tratamento farmacológico , Proteínas Proto-Oncogênicas p21(ras)/metabolismo , Piruvato Quinase/efeitos dos fármacos , Piruvato Quinase/metabolismo , Transdução de Sinais/efeitos dos fármacos , Sirolimo/farmacologia , Serina-Treonina Quinases TOR/metabolismo , Efeito Warburg em Oncologia/efeitos dos fármacos
6.
Antioxid Redox Signal ; 34(11): 831-844, 2021 04 10.
Artigo em Inglês | MEDLINE | ID: mdl-32586104

RESUMO

Significance: Persistent oxidative stress is a common feature of cancer cells, giving a specific weapon to selectively eliminate them. Ascorbate in pharmacological concentration can contribute to the suspended formation of hydroxyl radical via the Fenton reaction; thus, it can be an important element of the oxidative stress therapy against cancer cells. Recent Advances: The main components of ascorbate-induced cell death are DNA double-strand breaks via the production of hydroxyl radical and ATP depletion due to the activation of poly (ADP-ribose) polymerase 1. Presumably, DNA damage can be the primary contributor to the anticancer activity of pharmacological ascorbate, as opposed to the rupture of bioenergetics. The caspase independency of high-dose ascorbate-induced cell death proposed the possible involvement of several types of cell death, such as ferroptosis, necroptosis, and autophagy. Critical Issues: Ascorbate can target at least two key molecular features of cancer cells as a part of the anticancer therapy: the intrinsic or acquired resistance to cell death and the dysregulated metabolism of cancer cells. It seems probable that different concentrations of ascorbate alter the nature of induced cell death. Autophagy and necroptosis may play a role at intermediate concentrations, but caspase-independent apoptosis may dominate at higher concentrations. However, ascorbate behaves as an effective inhibitor of ferroptosis that may have crucial importance in its possible clinical application. Future Directions: The elucidation of the details and the links between high-dose ascorbate-induced cancer selective cell death mechanisms may give us a tool to form and apply synergistic cancer therapies. Antioxid. Redox Signal. 34, 831-844.


Assuntos
Ácido Ascórbico/uso terapêutico , Morte Celular/efeitos dos fármacos , Neoplasias/dietoterapia , Estresse Oxidativo/efeitos dos fármacos , Apoptose/efeitos dos fármacos , Autofagia/efeitos dos fármacos , Morte Celular/genética , Quebras de DNA de Cadeia Dupla/efeitos dos fármacos , Ferroptose/efeitos dos fármacos , Humanos , Necroptose/efeitos dos fármacos , Neoplasias/metabolismo , Neoplasias/patologia , Poli(ADP-Ribose) Polimerase-1/genética , Espécies Reativas de Oxigênio/metabolismo
7.
Molecules ; 25(7)2020 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-32231024

RESUMO

Cyclophosphamide is one of the most potent and reliable anti-cancer and immunosuppressive drugs. In our study, 33 individuals with different autoimmune diseases were treated with cyclophosphamide according to standard protocols. The responses to the treatments were determined by measuring the alteration of several typical parameters characterizing the given autoimmune diseases over time. We concluded that about 45% of the patients responded to the treatment. Patients were genotyped for polymorphisms of the CYP3A4, CYP2B6, GSTM1, GSTT1, and GSTP1 genes and disease remission cases were compared to the individual polymorphic genotypes. It was found that the GSTP1 I105V allelic variation significantly associated with the cyclophosphamide treatment-dependent disease-remissions. At the same time the GSH content of the erythrocytes in the patients with I105V allelic variation did not change. It appears that the individuals carrying the Ile105Val SNP in at least one copy had a significantly higher response rate to the treatment. Since this variant of GSTP1 can be characterized by lower conjugation capacity that results in an elongated and higher therapeutic dose of cyclophosphamide, our data suggest that the decreased activity of this variant of GSTP1 can be in the background of the more effective disease treatment.


Assuntos
Doenças Autoimunes/genética , Ciclofosfamida/farmacologia , Glutationa S-Transferase pi/genética , Imunossupressores/farmacologia , Variantes Farmacogenômicos , Polimorfismo Genético , Adulto , Idoso , Idoso de 80 Anos ou mais , Alelos , Doenças Autoimunes/diagnóstico , Doenças Autoimunes/tratamento farmacológico , Doenças Autoimunes/metabolismo , Biomarcadores , Ciclofosfamida/uso terapêutico , Sistema Enzimático do Citocromo P-450/genética , Sistema Enzimático do Citocromo P-450/metabolismo , Feminino , Frequência do Gene , Glutationa/sangue , Glutationa/metabolismo , Humanos , Imunossupressores/uso terapêutico , Masculino , Redes e Vias Metabólicas , Pessoa de Meia-Idade , Resultado do Tratamento , Adulto Jovem
8.
Pathol Oncol Res ; 26(3): 1797-1803, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31705481

RESUMO

Acetaminophen (APAP) induced hepatotoxicity involves activation of c-Jun amino-terminal kinase (JNK), mitochondrial damage and ER stress. BGP-15, a hydroximic acid derivative, has been reported to have hepatoprotective effects in APAP overdose induced liver damage. Effect of BGP-15 was further investigated on mitochondria in APAP-overdose induced acute liver injury in mice. We found that BGP-15 efficiently preserved mitochondrial morphology, and it caused a marked decrease in the number of damaged mitochondria. Attenuation of mitochondrial damage by BGP-15 is supported by immunohistochemistry as the TOMM20 label and the co-localized autophagy markers detected in the livers of APAP-treated mice were markedly reduced upon BGP-15 administration. This effect, along with the observed prevention of JNK activation likely contribute to the mitochondrial protective action of BGP-15.


Assuntos
Acetaminofen/toxicidade , Analgésicos não Narcóticos/toxicidade , Doença Hepática Induzida por Substâncias e Drogas/patologia , Inibidores Enzimáticos/farmacologia , Mitocôndrias/efeitos dos fármacos , Oximas/farmacologia , Piperidinas/farmacologia , Animais , Fígado/efeitos dos fármacos , Fígado/patologia , Camundongos
9.
Orv Hetil ; 160(52): 2073-2078, 2019 Dec.
Artigo em Húngaro | MEDLINE | ID: mdl-31868009

RESUMO

The confirmed incidence of new-onset adrenal gland hemorrhage has increased with the development of ultrasound diagnostics in recent years. Intrauterine developed cases are rarely recognized. Differential diagnosis of cystic lesions of the adrenal gland is often only possible after birth. In our case study, we report the ultrasonographic diagnosis and follow-up of a cystic lesion measuring 4 × 3 cm in the left fetal epigastrium in the 33rd gestational week. During pregnancy, multimodal imaging methods (both ultrasound and magnetic resonance) have confirmed the diagnosis of hemorrhage in the left adrenal gland. In the 37th gestational week, the hematoma completely resolved. At term, a 4150 gram neonate was delivered in good condition by an elective cesarean section. Postnatal endocrinological and follow-up ultrasound examinations did not find any disorder. This study is the first published case report in the literature that proves that fetal adrenal hemorrhage can intrauterin spontaneously absorb within a short period of time. Our case draws attention to the fact that adrenal bleeding may occur in the newborn regardless of birth trauma. It can also be assumed that the incidence of adrenal bleeding during pregnancy is higher than that reported in neonatal cases. Orv Hetil. 2019; 160(52): 2073-2078.


Assuntos
Doenças das Glândulas Suprarrenais/diagnóstico por imagem , Doenças das Glândulas Suprarrenais/diagnóstico , Glândulas Suprarrenais/diagnóstico por imagem , Glândulas Suprarrenais/patologia , Doenças Fetais/diagnóstico , Hemorragia/patologia , Ultrassonografia Pré-Natal/métodos , Cesárea , Diagnóstico Diferencial , Feminino , Humanos , Recém-Nascido , Gravidez
10.
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
11.
FASEB J ; 33(2): 2372-2387, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30277819

RESUMO

NF-E2-related factor 2 (NRF2) transcription factor has a fundamental role in cell homeostasis maintenance as one of the master regulators of oxidative and electrophilic stress responses. Previous studies have shown that a regulatory connection exists between NRF2 and autophagy during reactive oxygen species-generated oxidative stress. The aim of the present study was to investigate how autophagy is turned off during prolonged oxidative stress, to avoid overeating and destruction of essential cellular components. AMPK is a key cellular energy sensor highly conserved in eukaryotic organisms, and it has an essential role in autophagy activation at various stress events. Here the role of human AMPK and its Caenorhabditis elegans counterpart AAK-2 was explored upon oxidative stress. We investigated the regulatory connection between NRF2 and AMPK during oxidative stress induced by tert-butyl hydroperoxide (TBHP) in HEK293T cells and C. elegans. Putative conserved NRF2/protein skinhead-1 binding sites were found in AMPK/aak-2 genes by in silico analysis and were later confirmed experimentally by using EMSA. After addition of TBHP, NRF2 and AMPK showed a quick activation; AMPK was later down-regulated, however, while NRF2 level remained high. Autophagosome formation and Unc-51-like autophagy activating kinase 1 phosphorylation were initially stimulated, but they returned to basal values after 4 h of TBHP treatment. The silencing of NRF2 resulted in a constant activation of AMPK leading to hyperactivation of autophagy during oxidative stress. We observed the same effects in C. elegans demonstrating the conservation of this self-defense mechanism to save cells from hyperactivated autophagy upon prolonged oxidative stress. We conclude that NRF2 negatively regulates autophagy through delayed down-regulation of the expression of AMPK upon prolonged oxidative stress. This regulatory connection between NRF2 and AMPK may have an important role in understanding how autophagy is regulated in chronic human morbidities characterized by oxidative stress, such as neurodegenerative diseases, certain cancer types, and in metabolic diseases.-Kosztelnik, M., Kurucz, A., Papp, D., Jones, E., Sigmond, T., Barna, J., Traka, M. H., Lorincz, T., Szarka, A., Banhegyi, G., Vellai, T., Korcsmaros, T., Kapuy, O. Suppression of AMPK/aak-2 by NRF2/SKN-1 down-regulates autophagy during prolonged oxidative stress.


Assuntos
Autofagia , Proteínas de Caenorhabditis elegans/antagonistas & inibidores , Proteínas de Caenorhabditis elegans/metabolismo , Proteínas de Ligação a DNA/metabolismo , Regulação da Expressão Gênica , Fator 2 Relacionado a NF-E2/metabolismo , Estresse Oxidativo , Proteínas Quinases/química , Proteínas Serina-Treonina Quinases/antagonistas & inibidores , Fatores de Transcrição/metabolismo , Quinases Proteína-Quinases Ativadas por AMP , Proteínas Quinases Ativadas por AMP , Animais , Caenorhabditis elegans/genética , Caenorhabditis elegans/crescimento & desenvolvimento , Caenorhabditis elegans/metabolismo , Proteínas de Caenorhabditis elegans/genética , Proteínas de Ligação a DNA/genética , Regulação para Baixo , Células HEK293 , Humanos , Fator 2 Relacionado a NF-E2/genética , Oxirredução , Fosforilação , Proteínas Quinases/genética , Proteínas Quinases/metabolismo , Proteínas Serina-Treonina Quinases/genética , Proteínas Serina-Treonina Quinases/metabolismo , Fatores de Transcrição/genética
12.
Pathol Oncol Res ; 25(2): 669-679, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30443843

RESUMO

Pharmacologic ascorbate induced cell death and ferroptosis share common features such as iron dependency, production of ROS, lipid peroxidation, caspase independency and the possible involvement of autophagy. These observations lead us to hypothesize that ferroptosis may also be involved in cancer cell death due to pharmacologic ascorbate treatment. Thus cell death of HT-1080 cell line was induced by ferroptosis inducers and pharmacologic ascorbate then the mechanism of cell death was compared. The EC50 value of pharmacologic ascorbate on HT-1080 cell line was found to be 0.5 mM that is in the range of the most ascorbate sensitive cell lines. However either of the specific inhibitors of ferroptosis (ferrostatin-1 and liproxstatin-1) could not elevate the viability of pharmacologic ascorbate treated cells suggesting that ferroptosis was not involved in the pharmacologic ascorbate induced cell death. α-tocopherol that could effectively elevate the viability of erastin and RSL3 treated HT1080 cells failed to mitigate the cytotoxic effect of pharmacologic ascorbate further strengthened this assumption. Furthermore at lower concentrations (0.1-0.5 mM) ascorbate could avoid the effects of ferroptosis inducers. Our results indicate that pharmacologic ascorbate induced cytotoxicity and ferroptosis - albeit phenotypically they show similar traits - are governed by different mechanisms.


Assuntos
Antioxidantes/toxicidade , Ácido Ascórbico/toxicidade , Morte Celular/efeitos dos fármacos , Morte Celular/fisiologia , Linhagem Celular , Humanos , Peroxidação de Lipídeos/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo
13.
Antioxid Redox Signal ; 29(15): 1516-1533, 2018 11 20.
Artigo em Inglês | MEDLINE | ID: mdl-28974112

RESUMO

SIGNIFICANCE: Ascorbate (Asc) is an essential compound both in animals and plants, mostly due to its reducing properties, thereby playing a role in scavenging reactive oxygen species (ROS) and acting as a cofactor in various enzymatic reactions. Recent Advances: Growing number of evidence shows that excessive Asc accumulation may have negative effects on cellular functions both in humans and plants; inter alia it may negatively affect signaling mechanisms, cellular redox status, and contribute to the production of ROS via the Fenton reaction. CRITICAL ISSUES: Both plants and humans tightly control cellular Asc levels, possibly via biosynthesis, transport, and degradation, to maintain them in an optimum concentration range, which, among other factors, is essential to minimize the potentially harmful effects of Asc. On the contrary, the Fenton reaction induced by a high-dose Asc treatment in humans enables a potential cancer-selective cell death pathway. FUTURE DIRECTIONS: The elucidation of Asc induced cancer selective cell death mechanisms may give us a tool to apply Asc in cancer therapy. On the contrary, the regulatory mechanisms controlling cellular Asc levels are also to be considered, for example, when aiming at generating crops with elevated Asc levels.


Assuntos
Ácido Ascórbico/metabolismo , Plantas/metabolismo , Animais , Humanos , Espécies Reativas de Oxigênio/metabolismo
14.
J Pharmacol Toxicol Methods ; 88(Pt 1): 32-39, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28552277

RESUMO

INTRODUCTION: Glutathione (GSH) through its important function in the antioxidant protection of cells and in the conjugation of drugs and xenobiotics has crucial importance in pharmacology and toxicology. Since GSH is most often measured in liver tissue and different cell organelles it is important to choose the method that best suits for the determination of GSH. METHODS: The GSH content of cell organelles isolated from control and BSO-treated liver tissues was determined by the GSH-NEM-HPLC-UV, monochlorobimane-GSH-HPLC-fluorescence method and DTNB-GSH recycling assay to find the most suitable method for GSH determination from cell organelles. RESULTS: The GSH level of organelles could easily be measured by the monochlorobimane-HPLC-fluorescent method. The addition of monochlorobimane to the homogenisation buffer prevented the oxidation of GSH during isolation. The formation of monochlorobimane-GSH adduct was accelerated by the intrinsic GST activity of samples, however the omission of GST from the GSH standards could cause the overestimation of GSH content of biological samples. NEM is an excellent thiol protective agent and the GSH-NEM conjugate can be directly analysed by HPLC-UV, but the relatively high limit of detection made the method unsuitable for the determination of GSH from cell organelles. Although the DTNB-GSH recycling assay is quite simple and rapid the stabilization of GSH and the efficiency of detection lag behind the monochlorobimane-HPLC-fluorescent method. DISCUSSION: The monochlorobimane-HPLC-fluorescent method can be advised for the determination of GSH from pharmacologically and toxicological relevant cell organelles and liver tissue whilst addition of monochlorobimane to the homogenisation buffer prevented the autoxidation of GSH.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Retículo Endoplasmático/metabolismo , Glutationa/análise , Fígado/metabolismo , Mitocôndrias/metabolismo , Testes de Toxicidade/métodos , Animais , Butionina Sulfoximina/farmacologia , Ácido Ditionitrobenzoico/química , Inibidores Enzimáticos/farmacologia , Etilmaleimida/química , Corantes Fluorescentes/química , Glutamato-Cisteína Ligase/metabolismo , Glutationa/metabolismo , Fígado/citologia , Fígado/efeitos dos fármacos , Masculino , Oxirredução/efeitos dos fármacos , Pirazóis/farmacologia , Ratos , Ratos Wistar
15.
Pathol Oncol Res ; 22(2): 431-7, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26584568

RESUMO

Augmenter of liver regeneration (ALR) contributes to mitochondrial biogenesis, maintenance and to the physiological operation of mitochondria. The depletion of ALR has been widely studied and had serious consequences on the mitochondrial functions. However the inverse direction, the effect of the depletion of mitochondrial electron transfer chain and mtDNA on ALR expression has not been investigated yet. Thus mtDNA depleted, ρ(0) cell line was prepared to investigate the role of mitochondrial electron transfer chain and mtDNA on ALR expression. The depletion of mtDNA has not caused any difference at mRNA level, but at protein level the expression of ALR has been markedly increased. The regulatory role of ATP and ROS levels could be ruled out because the treatment of the parental cell line with different respiratory inhibitors and uncoupling agent could not provoke any changes in the protein level of ALR. The effect of mtDNA depletion on the protein level of ALR has been proved not to be liver specific, since the phenomenon could be observed in the case of two other, non-hepatic cell lines. It seems the level of mtDNA and/or its products may have regulatory role on the protein level of ALR. The up-regulation of ALR can be a part of the adaptive response in ρ(0) cells that preserves the structural integrity and the transmembrane potential despite the absence of protein components encoded by the mtDNA.


Assuntos
Proliferação de Células , DNA Mitocondrial/genética , Regeneração Hepática/fisiologia , Mitocôndrias/metabolismo , Neoplasias/genética , Neoplasias/metabolismo , Western Blotting , Transporte de Elétrons , Humanos , Mitocôndrias/patologia , Neoplasias/patologia , RNA Mensageiro/genética , Reação em Cadeia da Polimerase em Tempo Real , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Células Tumorais Cultivadas
16.
Pathol Oncol Res ; 21(4): 1115-21, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25962350

RESUMO

The recently described form of programmed cell death, ferroptosis can be induced by agents causing GSH depletion or the inhibition of GPX4. Ferroptosis clearly shows distinct morphologic, biochemical and genetic features from apoptosis, necrosis and autophagy. Since NAPQI the highly reactive metabolite of the widely applied analgesic and antipyretic, acetaminophen induces a cell death which can be characterized by GSH depletion, GPX inhibition and caspase independency the involvement of ferroptosis in acetaminophen induced cell death has been investigated. The specific ferroptosis inhibitor ferrostatin-1 failed to elevate the viability of acetaminophen treated HepG2 cells. It should be noticed that these cells do not form NAPQI due to the lack of phase I enzyme expression therefore GSH depletion cannot be observed. However in the case of acetaminophen treated primary mouse hepatocytes the significant elevation of cell viability could be observed upon ferrostatin-1 treatment. Similar to ferrostatin-1 treatment, the addition of the RIP1 kinase inhibitor necrostatin-1 could also elevate the viability of acetaminophen treated primary hepatocytes. Ferrostatin-1 has no influence on the expression of CYP2E1 or on the cellular GSH level which suggest that the protective effect of ferrostatin-1 in APAP induced cell death is not based on the reduced metabolism of APAP to NAPQI or on altered NAPQI conjugation by cellular GSH. Our results suggest that beyond necroptosis and apoptosis a third programmed cell death, ferroptosis is also involved in acetaminophen induced cell death in primary hepatocytes.


Assuntos
Acetaminofen/farmacologia , Apoptose/fisiologia , Morte Celular/efeitos dos fármacos , Animais , Benzoquinonas/farmacologia , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Cicloexilaminas/metabolismo , Citocromo P-450 CYP2E1/metabolismo , Proteínas Ativadoras de GTPase/metabolismo , Glutationa/metabolismo , Glutationa Peroxidase/metabolismo , Células Hep G2 , Hepatócitos/efeitos dos fármacos , Hepatócitos/metabolismo , Humanos , Imidazóis/farmacologia , Iminas/farmacologia , Indóis/farmacologia , Masculino , Camundongos , Fenilenodiaminas/metabolismo
17.
Int J Mol Sci ; 13(4): 4458-4483, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22605990

RESUMO

The life of any living organism can be defined as a hurdle due to different kind of stresses. As with all living organisms, plants are exposed to various abiotic stresses, such as drought, salinity, extreme temperatures and chemical toxicity. These primary stresses are often interconnected, and lead to the overproduction of reactive oxygen species (ROS) in plants, which are highly reactive and toxic and cause damage to proteins, lipids, carbohydrates and DNA, which ultimately results in oxidative stress. Stress-induced ROS accumulation is counteracted by enzymatic antioxidant systems and non-enzymatic low molecular weight metabolites, such as ascorbate, glutathione and α-tocopherol. The above mentioned low molecular weight antioxidants are also capable of chelating metal ions, reducing thus their catalytic activity to form ROS and also scavenge them. Hence, in plant cells, this triad of low molecular weight antioxidants (ascorbate, glutathione and α-tocopherol) form an important part of abiotic stress response. In this work we are presenting a review of abiotic stress responses connected to these antioxidants.


Assuntos
Ácido Ascórbico/metabolismo , Glutationa/metabolismo , Estresse Oxidativo/fisiologia , Plantas/metabolismo , alfa-Tocoferol/metabolismo , Adaptação Fisiológica , Antioxidantes/metabolismo , Ácido Ascórbico/química , Dano ao DNA/genética , DNA de Plantas/genética , Glutationa/química , Estresse Oxidativo/genética , Células Vegetais/metabolismo , Espécies Reativas de Oxigênio/metabolismo , alfa-Tocoferol/química
18.
Antioxid Redox Signal ; 16(8): 772-80, 2012 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-22142307

RESUMO

SIGNIFICANCE: The lumen of the endoplasmic reticulum (ER) constitutes a separate compartment with a special proteome and metabolome. The characteristic redox environment required for the optimal functioning of local pathways is defined by the redox couples of the main electron carriers. These molecules, glutathione, pyridine nucleotides, and ascorbic acid, are present within the ER, but their composition, concentration, and redox state are characteristically different from those observed in other subcellular compartments. Spatial and kinetic barriers contribute to the generation and maintenance of this special redox environment. RECENT ADVANCES: The ER redox has usually been considered from the perspective of oxidative protein folding, one of the major functions of the ER. Thus, the lumen has been described as a relatively oxidizing subcellular compartment. CRITICAL ISSUES: The ER redoxome has been scantily mapped. However, recent observations suggest that the redox systems in reduced and oxidized states are present simultaneously. The concerted actions of transmembrane uptake processes and local oxidoreductases as well as the absence of specific transport and enzyme activities maintain the oxidized state of the thiol-disulfide systems and the reduced state of the pyridine nucleotide redox systems. These states are prerequisites for the normal redox reactions localized in the ER. FUTURE DIRECTIONS: An outline of the interactions between the major electron carriers of the ER will contribute to a better understanding of human diseases related to ER redox homeostasis.


Assuntos
Retículo Endoplasmático/metabolismo , Nucleotídeos de Adenina/metabolismo , Animais , Ácido Ascórbico/metabolismo , Transporte de Elétrons , Estresse do Retículo Endoplasmático , Glutationa/metabolismo , Humanos , Oxirredução , Espécies Reativas de Oxigênio/metabolismo
19.
Reprod Biol Endocrinol ; 9: 124, 2011 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-21906313

RESUMO

OBJECTIVE: In this study, we determined circulating levels of C-reactive protein, several cytokines, chemokines, adhesion molecules and angiogenic factors along with those of leptin in healthy non-pregnant and pregnant women and preeclamptic patients, and investigated whether serum leptin levels were related to the clinical characteristics and measured laboratory parameters of the study participants. METHODS: Sixty preeclamptic patients, 60 healthy pregnant women and 59 healthy non-pregnant women were involved in this case-control study. Levels of leptin and transforming growth factor (TGF)-beta1 in maternal sera were assessed by ELISA. Serum levels of interleukin (IL)-1beta, IL-1 receptor antagonist (IL-1ra), IL-2, IL-4, IL-6, IL-8, IL-10, IL-12p40, IL-12p70, IL-18, interferon (IFN)-gamma, tumor necrosis factor (TNF)-alpha, interferon-gamma-inducible protein (IP)-10, monocyte chemotactic protein (MCP)-1, intercellular adhesion molecule (ICAM)-1 and vascular cell adhesion molecule (VCAM)-1 were determined by multiplex suspension array. Serum C-reactive protein (CRP) concentrations were measured by an autoanalyzer. Serum total soluble fms-like tyrosine kinase-1 (sFlt-1) and biologically active placental growth factor (PlGF) levels were determined by electrochemiluminescence immunoassay. For statistical analyses, non-parametric methods were applied. RESULTS: There were significant differences in most of the measured laboratory parameters among the three study groups except for serum IL-1beta and TGF-beta1 levels. Serum leptin levels were significantly higher in preeclamptic patients and healthy pregnant women than in healthy non-pregnant women. Additionally, preeclamptic patients had significantly higher leptin levels as compared to healthy pregnant women. Serum leptin levels were independently associated with BMI in healthy non-pregnant women. In healthy pregnant women, both BMI and serum CRP concentrations showed significant positive linear association with leptin levels. There were significant positive correlations between serum leptin concentrations of healthy pregnant women and systolic blood pressure, as well as serum levels of IP-10, while their serum leptin levels correlated inversely with fetal birth weight. In preeclamptic patients, a significant positive correlation was observed between serum concentrations of leptin and IP-10. Furthermore, elevated serum leptin level and sFlt-1/PlGF ratio had an additive (joint) effect in the risk of preeclampsia, as shown by the substantially higher odds ratios of their combination than of either alone. CONCLUSIONS: Simultaneous measurement of leptin with several inflammatory molecules and angiogenic factors in this study enabled us to investigate their relationship, which can help to understand the role of circulating leptin in normal pregnancy and preeclampsia.


Assuntos
Proteínas Angiogênicas/sangue , Moléculas de Adesão Celular/sangue , Citocinas/sangue , Leptina/sangue , Pré-Eclâmpsia/sangue , Pré-Eclâmpsia/diagnóstico , Proteínas da Gravidez/sangue , Algoritmos , Biomarcadores/sangue , Peso ao Nascer , Índice de Massa Corporal , Proteína C-Reativa/análise , Estudos de Casos e Controles , Quimiocina CXCL10/sangue , Quimiocinas/sangue , Feminino , Humanos , Recém-Nascido , Masculino , Fator de Crescimento Placentário , Pré-Eclâmpsia/imunologia , Gravidez , Sensibilidade e Especificidade , Receptor 1 de Fatores de Crescimento do Endotélio Vascular/sangue
20.
Clin Chim Acta ; 412(21-22): 1957-62, 2011 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-21756887

RESUMO

BACKGROUND: We have previously reported that serum levels of 70 kDa heat shock protein (Hsp70, HSPA1A) are increased and reflect systemic inflammation, oxidative stress and hepatocellular injury in preeclampsia. The purpose of this study was to determine whether increased serum Hsp70 concentrations in women with preeclampsia are related to circulating levels of cytokines, chemokines, adhesion molecules and angiogenic factors, the key players in the pathogenesis of the disease. METHODS: Sixty preeclamptic patients and 60 normotensive, healthy pregnant women were involved in this case-control study. Levels of Hsp70 (HSPA1A) and transforming growth factor (TGF)-beta1 in maternal sera were assessed by ELISA. Serum levels of interleukin (IL)-1 beta, IL-1 receptor antagonist, IL-2, IL-4, IL-6, IL-8, IL-10, IL-12p40, IL-12p70, IL-18, interferon (IFN)-gamma, tumor necrosis factor (TNF)-alpha, interferon-gamma-inducible protein (IP)-10, monocyte chemotactic protein (MCP)-1, intercellular adhesion molecule (ICAM)-1 and vascular cell adhesion molecule (VCAM)-1 were determined by multiplex suspension array. Serum total soluble fms-like tyrosine kinase-1 (sFlt-1) and biologically active placental growth factor (PlGF) levels were measured by electrochemiluminescence immunoassay. For statistical analyses, the Mann-Whitney U-test, the Fisher exact and Pearson chi-square tests, the Spearman rank order correlation, multiple linear regression and logistic regression were applied. RESULTS: Serum levels of Hsp70 were significantly higher in preeclamptic patients than in healthy pregnant women. Additionally, most of the measured inflammatory variables differed significantly between the two study groups except for serum IL-1 beta and TGF-beta1 levels and IL-18/IL-12p70 and IL-12p70/IL-12p40 ratios, indicating a bias toward a pro-inflammatory status in preeclampsia. Preeclamptic patients had significantly higher sFlt-1 levels and sFlt-1/PlGF ratio and significantly lower PlGF concentrations as compared to healthy pregnant women. In the preeclamptic group, serum Hsp70 concentrations showed significant correlations with serum levels of IL-12p40 (R=0.59, p<0.001), MCP-1 (R=0.43, p<0.001), ICAM-1 (R=0.39, p=0.0020) and VCAM-1 (R=0.46, p<0.001). Furthermore, elevated serum Hsp70 level and sFlt-1/PlGF ratio had a synergistic (joint) effect in the risk of preeclampsia, as shown by the substantially higher odds ratios of their combination than of either alone. CONCLUSIONS: Increased serum Hsp70 concentrations in women with preeclampsia were associated with pro-inflammatory changes in circulating cytokine profile, suggesting that circulating Hsp70 might contribute to the development of the excessive systemic inflammatory response characteristic of the maternal syndrome of the disease.


Assuntos
Proteínas Angiogênicas/sangue , Moléculas de Adesão Celular/sangue , Citocinas/sangue , Proteínas de Choque Térmico HSP70/sangue , Pré-Eclâmpsia/sangue , Adulto , Proteínas Angiogênicas/imunologia , Biomarcadores/sangue , Estudos de Casos e Controles , Moléculas de Adesão Celular/imunologia , Citocinas/imunologia , Feminino , Proteínas de Choque Térmico HSP70/imunologia , Humanos , Pré-Eclâmpsia/imunologia , Gravidez
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