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1.
Chem Res Toxicol ; 35(1): 30-42, 2022 01 17.
Artigo em Inglês | MEDLINE | ID: mdl-34957817

RESUMO

Fentanyl and fentanyl analogues (also called fentalogs) are used as medical prescriptions to treat pain for a long time. Apart from their pharmaceutical applications, they are misused immensely, causing the opioid crisis. Fentanyl and its analogues are produced in clandestine laboratories and sold over dark Web markets to different parts of the world, leading to a rise in the death rate due to drug overdose. This is because the users are unaware of the lethal effects of the newer forms of fentalogs. Unlike other drugs, these fentalogs cannot be detected easily, as very little data are available, and this is one of the major reasons for the risk of life-threatening poisoning or deaths. Hence, rigorous studies of these drugs and their possible metabolites are required. It is also necessary to develop techniques for the detection of minute traces of metabolites in biological fluids. This Review provides an overview of the application of hyphenated chromatographic techniques used to analyze multiple novel fentalogs, using in vivo and in vitro methods. The article focuses on the metabolites formed in phase I and phase II processes in biological specimens obtained in recent cases of drug abuse and overdose deaths that could be useful for the detection and differentiation of multiple fentalogs.


Assuntos
Fentanila/análise , Drogas Ilícitas/análise , Detecção do Abuso de Substâncias , Líquidos Corporais/química , Cromatografia , Fentanila/análogos & derivados , Fentanila/metabolismo , Humanos , Drogas Ilícitas/metabolismo , Estrutura Molecular
2.
Biomedicines ; 6(1)2017 12 26.
Artigo em Inglês | MEDLINE | ID: mdl-29278364

RESUMO

The objective of this study was to examine the combined effect of Interferon-gamma (IFN-γ) and Tumor Necrosis factor-alpha (TNF-α) on cytotoxicity and expression of prostate apoptosis response-4 (Par-4) and Par-4 interacting proteins B-cell lymphoma (Bcl-2), nuclear factor kappa-light-chain-enhancer of activated B cells/p65 subunit (NF-κB/p65), Ak mouse strain thymoma (Akt) in human neuroblastoma (NB) cells. Materials and methods included human neuroblastoma cell lines-SK-N-MC, SK-N-SH, and SH-SY5Y, which were treated with IFN-γ and TNF-α individually, or in combination, and were assessed for viability by tetrazolium (MTT) assay. Apoptosis was monitored by hypodiploid population (by flow cytometry), DNA fragmentation, Poly (ADP-ribose) polymerase (PARP) cleavage, and caspase-8 activity. Transcript level of Par-4 was measured by RT-PCR. Protein levels of Par-4 and suppressor of cytokine signaling 3 (SOCS-3) were assessed by immunoblotting. Cellular localization of Par-4 and p65 was examined by immunofluorescence. Unbiased transcript analysis for IFN-γ, TNF-α, and Par-4 were analyzed from three independent clinical datasets from neuroblastoma patients. In terms of results, SK-N-MC cells treated with a combination of, but not individually with, IFN-γ and TNF-α induced apoptosis characterized by hypodiploidy, DNA fragmentation, PARP cleavage, and increased caspase-8 activity. Apoptosis was associated with up-regulation of Par-4 mRNA and protein expression. Immunofluorescence studies revealed that Par-4 was localized exclusively in cytoplasm in SK-N-MC cells cultured for 24 h. but showed nuclear localization at 48 h. Treatment with IFN-γ and TNF-α together enhanced the intensity of nuclear Par-4. In gene expression, data from human neuroblastoma patients, levels of IFN-γ, and TNF-α have strong synergy with Par-4 expression and provide good survival advantage. The findings also demonstrated that apoptosis was associated with reduced level of pro-survival proteins-Bcl-2 and Akt and NF-κB/p65. Furthermore, the apoptotic effect induced by IFN-γ-induced Signal Transducer and Activator of Transcription-1(STAT-1), and could be due to down-regulation of suppressor of cytokine signaling-3 (SOCS3). The study concludes that a combinatorial approach using IFN-γ and TNF-α can be explored to maximize the effect in chemotherapy in neuroblastoma, and implies a role for Par-4 in the process.

3.
J Environ Manage ; 180: 351-8, 2016 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-27254294

RESUMO

Tubular upflow microbial fuel cell (MFC) utilizing sea food processing wastewater was evaluated for wastewater treatment efficiency and power generation. At an organic loading rate (OLR) of 0.6 g d(-1), the MFC accomplished total and soluble chemical oxygen demand (COD) removal of 83 and 95%, respectively. A maximum power density of 105 mW m(-2) (2.21 W m(-3)) was achieved at an OLR of 2.57 g d(-1). The predominant bacterial communities of anode biofilm were identified as RB1A (LC035455), RB1B (LC035456), RB1C (LC035457) and RB1E (LC035458). All the four strains belonged to genera Stenotrophomonas. The results of the study reaffirms that the seafood processing wastewater can be treated in an upflow MFC for simultaneous power generation and wastewater treatment.


Assuntos
Fontes de Energia Bioelétrica/microbiologia , Biofilmes , Stenotrophomonas/metabolismo , Eliminação de Resíduos Líquidos/métodos , Águas Residuárias/microbiologia , Purificação da Água/métodos , Análise da Demanda Biológica de Oxigênio , Eletricidade , Eletrodos , Alimentos Marinhos , Stenotrophomonas/classificação , Águas Residuárias/análise
4.
FEBS Open Bio ; 5: 8-19, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25685660

RESUMO

Glioblastoma multiforme (GBM) is the most malignant form of brain tumor and is associated with resistance to conventional therapy and poor patient survival. Prostate apoptosis response (Par)-4, a tumor suppressor, is expressed as both an intracellular and secretory/extracellular protein. Though secretory Par-4 induces apoptosis in cancer cells, its potential in drug-resistant tumors remains to be fully explored. Multicellular spheroids (MCS) of cancer cells often acquire multi-drug resistance and serve as ideal experimental models. We investigated the role of Par-4 in Tamoxifen (TAM)-induced cell death in MCS of human cell lines and primary cultures of GBM tumors. TCGA and REMBRANT data analysis revealed that low levels of Par-4 correlated with low survival period (21.85 ± 19.30 days) in GBM but not in astrocytomas (59.13 ± 47.26 days) and oligodendrogliomas (58.04 ± 59.80 days) suggesting low PAWR expression as a predictive risk factor in GBM. Consistently, MCS of human cell lines and primary cultures displayed low Par-4 expression, high level of chemo-resistance genes and were resistant to TAM-induced cytotoxicity. In monolayer cells, TAM-induced cytotoxicity was associated with enhanced expression of Par-4 and was alleviated by silencing of Par-4 using specific siRNA. TAM effectively induced secretory Par-4 in conditioned medium (CM) of cells cultured as monolayer but not in MCS. Moreover, MCS were rendered sensitive to TAM-induced cell death by exposure to conditioned medium (CM)-containing Par-4 (derived from TAM-treated monolayer cells). Also TAM reduced the expression of Akt and PKCζ in GBM cells cultured as monolayer but not in MCS. Importantly, combination of TAM with inhibitors to PI3K inhibitor (LY294002) or PKCζ resulted in secretion of Par-4 and cell death in MCS. Since membrane GRP78 is overexpressed in most cancer cells but not normal cells, and secretory Par-4 induces apoptosis by binding to membrane GRP78, secretory Par-4 is an attractive candidate for potentially overcoming therapy-resistance not only in malignant glioma but in broad spectrum of cancers.

5.
Bioresour Technol ; 173: 32-41, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25280111

RESUMO

In this investigation, an effort was made to pretreat surplus waste activated sludge (WAS) inexpensively by a novel combined process involving thermo chemical disperser pretreatment. This pretreatment was found to be efficient at a specific energy (SE) consumption of 3360.94 kJ/kg TS, with the chemical oxygen demand (COD) solubilization of 20%. This was comparatively higher than thermo chemically treated sludge where the solubilization was found to be 15.5% at a specific energy consumption of 10,330 kJ/kg TS respectively. Higher production of volatile fatty acids (VFA) (675 mg/L) in anaerobic fermentation of pretreated WAS indicates better hydrolysis performance. The biogas production potential of sludge pretreated through this combined technique was found to be 0.455 (L/gVS) and comparatively higher than thermo chemically pretreated sludge. Economic investigation provides 90% net energy savings in this combined pretreatment. Therefore, this combined process was considered to be potentially effective and economical in sludge disintegration.


Assuntos
Bactérias Anaeróbias/metabolismo , Metano/metabolismo , Eliminação de Resíduos/métodos , Esgotos/química , Esgotos/microbiologia , Hidróxido de Sódio/química , Águas Residuárias/microbiologia , Análise da Demanda Biológica de Oxigênio , Análise Custo-Benefício , Transferência de Energia , Índia , Metano/isolamento & purificação , Eliminação de Resíduos/economia , Hidróxido de Sódio/economia , Águas Residuárias/economia
6.
Bioresour Technol ; 168: 159-66, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24559742

RESUMO

In this study, the role of sodium dodecyl sulfate (SDS) was explored for the removal of extracellular polymeric substance (EPS) from waste activated sludge (WAS) followed by enzymatic bacterial pretreatment, which enhanced the subsequent anaerobic biodegradability. EPS was removed with 0.02 g/g SS of SDS. In the results of pretreatment, the suspended solids reduction and chemical oxygen demand solubilization were found to be 25.7% and 19.79% for deflocculated and bacterially pretreated sludge, whereas they were found to be 15.7% and 11% for flocculated sludge (without EPS removal and bacterially pretreated) and 7.85% and 6% for control sludge (raw sludge), respectively. Upon examining the anaerobic biodegradability, the biogas yield potential of deflocculated and bacterially pretreated, flocculated, deflocculated alone, and control sludges were found to be 0.467 L/(g VS), 0.355 L/(g VS), 0.315 L/(g VS), and 0.212 L/(g VS), respectively. Thus, the deflocculation and bacterial pretreatment improved the anaerobic biodegradability efficiently.


Assuntos
Bactérias/metabolismo , Esgotos/microbiologia , Tensoativos/farmacologia , Álcalis/farmacologia , Anaerobiose/efeitos dos fármacos , Bactérias/efeitos dos fármacos , Bactérias/crescimento & desenvolvimento , Proteínas de Bactérias/análise , Biodegradação Ambiental/efeitos dos fármacos , Análise da Demanda Biológica de Oxigênio , Biopolímeros/isolamento & purificação , Carboidratos/análise , Concentração de Íons de Hidrogênio , Índia , Cinética , Dodecilsulfato de Sódio/farmacologia
7.
PLoS One ; 9(2): e88505, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24523904

RESUMO

Gliomas are the most common and aggressive of brain tumors in adults. Cancer stem cells (CSC) contribute to chemoresistance in many solid tumors including gliomas. The function of prostate apoptosis response-4 (Par-4) as a pro-apoptotic protein is well documented in many cancers; however, its role in CSC remains obscure. In this study, we aimed to explore the role of Par-4 in drug-induced cytotoxicity using human glioma stem cell line--HNGC-2 and primary culture (G1) derived from high grade glioma. We show that among the panel of drugs- lomustine, carmustine, UCN-01, oxaliplatin, temozolomide and tamoxifen (TAM) screened, only TAM induced cell death and up-regulated Par-4 levels significantly. TAM-induced apoptosis was confirmed by PARP cleavage, Annexin V and propidium iodide staining and caspase-3 activity. Knock down of Par-4 by siRNA inhibited cell death by TAM, suggesting the role of Par-4 in induction of apoptosis. We also demonstrate that the mechanism involves break down of mitochondrial membrane potential, down regulation of Bcl-2 and reduced activation of Akt and ERK 42/44. Secretory Par-4 and GRP-78 were significantly expressed in HNGC-2 cells on exposure to TAM and specific antibodies to these molecules inhibited cell death suggesting that extrinsic Par-4 is important in TAM-induced apoptosis. Interestingly, TAM decreased the expression of neural stem cell markers--Nestin, Bmi1, Vimentin, Sox2, and Musashi in HNGC-2 cell line and G1 cells implicating its potential as a stemness inhibiting drug. Based on these data and our findings that enhanced levels of Par-4 sensitize the resistant glioma stem cells to drug-induced apoptosis, we propose that Par-4 may be explored for evaluating anti-tumor agents in CSC.


Assuntos
Proteínas Reguladoras de Apoptose/metabolismo , Apoptose , Neoplasias Encefálicas/metabolismo , Resistencia a Medicamentos Antineoplásicos , Glioma/metabolismo , Células-Tronco Neoplásicas/citologia , Antineoplásicos/farmacologia , Neoplasias Encefálicas/patologia , Caspase 3/metabolismo , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Regulação Neoplásica da Expressão Gênica , Glioma/patologia , Humanos , Membranas Mitocondriais/metabolismo , Células-Tronco Neoplásicas/efeitos dos fármacos , Tamoxifeno/farmacologia
8.
J Cell Biochem ; 114(4): 854-63, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23097134

RESUMO

Sodium valproate (VPA) has been recently identified as a selective class I histone deacetylase (HDAC) inhibitor and explored for its potential as an anti-cancer agent. The anti-cancer properties of VPA are generally attributed to its HDAC inhibitory activity indicating a clear overlap of these two actions, but the underlying mechanisms of its anti-tumor effects are not clearly elucidated. The present study aimed to delineate the molecular mechanism of VPA in potentiating cytotoxic effects of anti-cancer drugs with focus on inhibition of HDAC activity. Using human neuroblastoma cell lines, SK-N-MC, SH-SY5Y, and SK-N-SH, we show that non-toxic dose (2 mM) of VPA enhanced staurosporine (STS)-induced cell death as assessed by MTT assay, PARP cleavage, hypodiploidy, and caspase 3 activity. Mechanistically, the effect of VPA was mediated by down regulation of survivin, an anti-apoptotic protein crucial in resistance to STS-mediated cytotoxicity, through Akt pathway. Knock down of class I HDAC isoforms remarkably inhibited HDAC activity comparable with that of VPA but had no effect on STS-induced apoptosis. Moreover, MS-275, a structurally distinct class I HDAC inhibitor did not affect STS-mediated apoptosis, nor decrease the levels of survivin and Akt. Valpromide (VPM), an amide analog of VPA that does not inhibit HDAC also potentiated cell death in NB cells associated with decreased survivin and Akt levels suggesting that HDAC inhibition might not be crucial for STS-induced apoptosis. The study provides new information on the possible molecular mechanism of VPA in apoptosis that can be explored in combination therapy in cancer.


Assuntos
Apoptose , Proteínas Inibidoras de Apoptose/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Estaurosporina/farmacologia , Ácido Valproico/farmacologia , Antineoplásicos/farmacologia , Benzamidas/farmacologia , Caspase 3/metabolismo , Linhagem Celular Tumoral , Sobrevivência Celular , Relação Dose-Resposta a Droga , Regulação para Baixo , Sinergismo Farmacológico , Ativação Enzimática , Pontos de Checagem da Fase G2 do Ciclo Celular , Histona Desacetilase 1/antagonistas & inibidores , Histona Desacetilase 1/genética , Histona Desacetilase 1/metabolismo , Inibidores de Histona Desacetilases/farmacologia , Humanos , Proteínas Inibidoras de Apoptose/genética , Isoenzimas/genética , Isoenzimas/metabolismo , Neuroblastoma/metabolismo , Neuroblastoma/patologia , Proteólise , Proteínas Proto-Oncogênicas c-akt/genética , Piridinas/farmacologia , Survivina , Ácido Valproico/análogos & derivados
11.
Mol Carcinog ; 47(2): 126-36, 2008 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-17849421

RESUMO

Tumor associated macrophages (TAMs) constitute a substantial mass in gliomas. The activated macrophages secrete various cytokines that affect diverse functions of tumors. The aim of this study was to elucidate the role of Akt and NF-kappaB pathways in resistance to TNF-alpha mediated cell death in human gliomas using monolayers and multicellular spheroids (MCS) as in vitro models. Akt and NF-kappaB are constitutively expressed and intimately involved in progression of gliomas. The activation of these pathways also renders the tumors resistant to conventional treatments including chemotherapy. While PI3K/Akt is shown to regulate the NF-kappaB activation in diverse systems, other studies place NF-kappaB upstream of Akt activation. Using a stable IkappaBalpha mutant LN-18 cell line and pharmacological inhibitors to PI3K/Akt (LY294002) and Akt (Akt2), we provide evidence that Akt and NF-kappaB are activated independently on stimulation with TNF-alpha and both the pathways contribute towards resistance to TNF-alpha mediated cell death. TNF-alpha-induced NF-kappaB activation independent of PI3K/Akt pathway was also confirmed in human glioma cell lines-LN-229 and U373MG. We also show that NF-kappaB and Akt are activated during spheroidogenesis and their expression is further enhanced on stimulation with TNF-alpha implicating their involvement in resistance to cell death. The findings thus underscore the relevance of spheroids as appropriate in vitro models for studying the signaling pathways in drug induced resistance.


Assuntos
Neoplasias Encefálicas/patologia , Glioma/patologia , NF-kappa B/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Fator de Necrose Tumoral alfa/farmacologia , Apoptose/efeitos dos fármacos , Sequência de Bases , Neoplasias Encefálicas/enzimologia , Neoplasias Encefálicas/metabolismo , Linhagem Celular Tumoral , Primers do DNA , Ensaio de Desvio de Mobilidade Eletroforética , Ativação Enzimática , Glioma/enzimologia , Glioma/metabolismo , Humanos , Microscopia Confocal
12.
Mol Cancer ; 6: 42, 2007 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-17565690

RESUMO

BACKGROUND: The role of TNF-alpha in affecting the fate of tumors is controversial, while some studies have reported apoptotic or necrotic effects of TNF-alpha, others provide evidence that endogenous TNF-alpha promotes growth and development of tumors. Understanding the mechanism(s) of TNF-alpha mediated growth arrest will be important in unraveling the contribution of tissue associated macrophages in tumor resistance. The aim of this study was to investigate the role of Cyclin Dependent Kinase Inhibitors (CDKI)--21cip/waf1 and p27kip1 in TNF-alpha mediated responses in context with p53 and activation of NF-kappaB and Akt pathways. The study was done with human glioma cell lines -LN-18 and LN-229 cells, using monolayer cultures and Multicellular Spheroids (MCS) as in vitro models. RESULTS: TNF-alpha induced inhibition of proliferation and enhanced the expression of p21cip/waf1 and p27kip1 in LN-18 cells. p21 was induced on exposure to TNF-alpha, localized exclusively in the nucleus and functioned as an inhibitor of cell cycle but not as an antiapoptotic protein. In contrast, p27 was constitutively expressed, localized predominantly in the cytoplasm and was not involved in arrest of proliferation. Our data using IkappaBalpha mutant LN-18 cells and PI3K/Akt inhibitor-LY294002 revealed that the expression of p21 is regulated by NF-kappaB. Loss of IkappaBalpha function in LN-229 cells (p53 positive) did not influence TNF-alpha induced accumulation of pp53 (Ser-20 p53) suggesting that p53 was not down stream of NF-kappaB. Spheroidogenesis enhanced p27 expression and p21 induced by TNF-alpha was significantly increased in the MCS compared to monolayers. CONCLUSION: This study demarcates the functional roles for CDKIs-p21cip/waf1 and p27kip1 during TNF-alpha stimulated responses in LN-18 glioma cells. Our findings provide evidence that TNF-alpha-induced p21 might be regulated by NF-kappaB or p53 independently. p21 functions as an inhibitor of cell proliferation and does not have a direct role in rendering the cells resistant to TNF-alpha mediated cytotoxicity.


Assuntos
Neoplasias Encefálicas/metabolismo , Inibidor de Quinase Dependente de Ciclina p21/metabolismo , Inibidor de Quinase Dependente de Ciclina p27/metabolismo , Glioma/metabolismo , Fator de Necrose Tumoral alfa/metabolismo , Linhagem Celular Tumoral , Núcleo Celular/metabolismo , Proliferação de Células , Citoplasma/metabolismo , Citometria de Fluxo , Humanos , NF-kappa B/metabolismo , RNA Interferente Pequeno , Receptores Tipo I de Fatores de Necrose Tumoral/metabolismo , Receptores Tipo II do Fator de Necrose Tumoral/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Esferoides Celulares , Proteína Supressora de Tumor p53/metabolismo
13.
Free Radic Biol Med ; 41(3): 431-42, 2006 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-16843824

RESUMO

Reactive oxygen species (ROS) and caspases 8, 9, and 3 are reported to be crucial players in apoptosis induced by various stimuli. Recently, caspase 2 has been implicated in stress-induced apoptosis but the exact mechanism remains unclear. In this study, we report that ROS generation led to activation of caspase 2 during beta-carotene-induced apoptosis in the human leukemic T cell line Molt 4. The apoptosis progressed by simultaneous activation of caspases 8 and 9, and a cross talk between these initiator caspases was mediated by the proapoptotic protein Bid. Inhibition of caspases 2, 8, 9, and 3 independently suppressed the caspase cascade. The kinetics and function of caspase 2 were similar to those of caspase 3, suggesting its role as an effector caspase. Interestingly, beta-carotene-induced apoptosis was caspase 2 dependent but caspase 3 independent. The study also revealed cleavage of the antiapoptotic protein BclXL as an important event during apoptosis, which was regulated by ROS. The mechanistic studies identify a functional link between ROS and the caspase cascade involving caspase 2 and cleavage of BclXL. The interdependence of caspases 8, 9, 2, and 3 in the cascade provides evidence for the presence of an extensive feedback amplification loop in beta-carotene-induced apoptosis in Molt 4 cells.


Assuntos
Apoptose/efeitos dos fármacos , Caspase 2/metabolismo , Espécies Reativas de Oxigênio/metabolismo , beta Caroteno/farmacologia , Caspase 3/metabolismo , Linhagem Celular Tumoral , Ativação Enzimática/efeitos dos fármacos , Proteína Ligante Fas/metabolismo , Humanos , Potenciais da Membrana/efeitos dos fármacos , Membranas Mitocondriais/efeitos dos fármacos , Membranas Mitocondriais/metabolismo , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Transdução de Sinais/efeitos dos fármacos
14.
Neoplasia ; 6(1): 29-40, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-15068669

RESUMO

Survivin, a member of the inhibitor of apoptosis (IAP) gene family, plays an important role in both the regulation of cell cycle and the inhibition of apoptosis, and is frequently overexpressed in many tumor types. In neuroblastomas, the expression of survivin correlates with a more aggressive and histologically unfavorable disease. Survivin is predominantly a cytoplasmic protein that is expressed in a cell cycle-dependent manner, increasing in the G2/M phase of the cell cycle followed by a rapid decline in the G1 phase. Recently, the role of survivin in resistance to chemotherapy has become an area of intensive investigation. In this study, we demonstrate a phase-specific resistance due to survivin in staurosporine (STS)-induced apoptosis in the human neuroblastoma cell line SK-N-MC. G2/M-arrested cultures show an upregulation of survivin expression and are more resistant, whereas G1-phase cells that show decreased levels of survivin are more sensitive to apoptosis. Localization studies revealed differences in the distribution of survivin in two synchronized populations, with G1 cells having weakly positive staining confined to the nucleus, in contrast to G2/M cells that depicted a more uniform and intense expression of survivin throughout the cell. In our experimental system, STS induced apoptosis through the mitochondrial-caspase 9-mediated pathway. Retention of survivin in G1 cells by inhibition of the ubiquitin-proteosome pathway or inhibition of caspase 9 protected the cells against apoptosis. Our data suggest that survivin exerts its antiapoptotic effect by inhibiting caspase 9 activity, an important event in STS-mediated apoptosis. In context with cell cycle-dependent responses to chemotherapy, the data from this study suggest the possibility of exploiting the survivin pathway for inducing apoptosis in tumor cells.


Assuntos
Apoptose/fisiologia , Caspases/metabolismo , Ciclo Celular/fisiologia , Resistencia a Medicamentos Antineoplásicos/fisiologia , Proteínas Associadas aos Microtúbulos/metabolismo , Apoptose/efeitos dos fármacos , Western Blotting , Caspase 9 , Linhagem Celular Tumoral , Núcleo Celular/metabolismo , Citoplasma/metabolismo , Ativação Enzimática , Inibidores Enzimáticos/farmacologia , Citometria de Fluxo , Humanos , Imuno-Histoquímica , Marcação In Situ das Extremidades Cortadas , Proteínas Inibidoras de Apoptose , Potenciais da Membrana/efeitos dos fármacos , Potenciais da Membrana/fisiologia , Microscopia Confocal , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/fisiologia , Proteínas de Neoplasias , Neuroblastoma/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Estaurosporina/farmacologia , Survivina , Transfecção , Regulação para Cima
15.
J Chem Neuroanat ; 26(2): 109-18, 2003 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-14599660

RESUMO

Free radicals are involved in neuronal damage. The present study was aimed to investigate the protective effect of sodium pyruvate-a free radical scavenger against hydrogen peroxide (H(2)O(2)) induced apoptosis in human neuroblastoma cell line-SK-N-MC. On exposure to H(2)O(2) (0.025 mM) cells exhibited apoptosis within 24 h, demonstrating a high caspase 3 activity by 3 h followed by cleavage of PARP that was maximum at 24 h. A break down in the mitochondrial membrane potential was observed 3 h onwards. Sodium pyruvate protected cells significantly (P<0.05) against apoptosis in a dose dependent manner as assessed for cell viability by dye exclusion method and apoptosis by TUNEL. Sodium pyruvate significantly inhibited caspase 3 activity, cleavage of PARP and breakdown of mitochondrial membrane potential. These data suggest that sodium pyruvate protects neuronal damage caused by H(2)O(2).


Assuntos
Antioxidantes , Apoptose/efeitos dos fármacos , Neoplasias Encefálicas/patologia , Peróxido de Hidrogênio/antagonistas & inibidores , Peróxido de Hidrogênio/toxicidade , Neuroblastoma/patologia , Fármacos Neuroprotetores , Oxidantes/toxicidade , Ácido Pirúvico/farmacologia , Western Blotting , Caspase 3 , Caspases/biossíntese , Linhagem Celular Tumoral , Sobrevivência Celular , Colorimetria , Fragmentação do DNA , Eletroforese em Gel de Poliacrilamida , Citometria de Fluxo , Humanos , Marcação In Situ das Extremidades Cortadas , Potenciais da Membrana/fisiologia
16.
Experientia ; 32(11): 1412-3, 1976 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-991983

RESUMO

The levels of protein and ribonucleic acid in the cerebrum, cerebellum, optic lobes and medulla oblongata of normal and alloxan-diabetic rats were measured. In general, the protein content and levels of ribonucleic acid in the broad compartments of the brain of rat decreased during diabetes.


Assuntos
Encéfalo/metabolismo , Diabetes Mellitus Experimental/metabolismo , Proteínas do Tecido Nervoso/metabolismo , RNA/metabolismo , Animais , Cerebelo/metabolismo , Feminino , Masculino , Bulbo/metabolismo , Lobo Óptico de Animais não Mamíferos/metabolismo , Ratos
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