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1.
Int J Mol Sci ; 24(18)2023 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-37762231

RESUMO

A chemotherapeutic approach is crucial in malignancy management, which is often challenging due to the development of chemoresistance. Over time, chemo-resistant cancer cells rapidly repopulate and metastasize, increasing the recurrence rate in cancer patients. Targeting these destined cancer cells is more troublesome for clinicians, as they share biology and molecular cross-talks with normal cells. However, the recent insights into the metabolic profiles of chemo-resistant cancer cells surprisingly illustrated the activation of distinct pathways compared with chemo-sensitive or primary cancer cells. These distinct metabolic dynamics are vital and contribute to the shift from chemo-sensitivity to chemo-resistance in cancer. This review will discuss the important metabolic alterations in cancer cells that lead to drug resistance.


Assuntos
Resistencia a Medicamentos Antineoplásicos , Neoplasias , Humanos , Glucose/metabolismo
2.
Front Endocrinol (Lausanne) ; 14: 1124419, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36875474

RESUMO

Cellular aging is the most severe risk factor for neurodegenerative disease. Simultaneously, oxidative stress (OS) is a critical factor in the aging process, resulting from an imbalance between reactive oxygen and nitrogen species and the antioxidant defense system. Emerging evidence indicates that OS is a common cause of several age-related brain pathologies, including cerebrovascular diseases. Elevated OS disrupts endothelial functional ability by diminishing the bioavailability of nitric oxide (a vascular dilator), induces atherosclerosis, and impairs vasculature, which are all common characteristics of cerebrovascular disease. In this review, we summarize evidence supporting an active role of OS in cerebrovascular disease progression, focusing primarily on stroke pathogenesis. We briefly discuss hypertension, diabetes, heart disease, and genetic factors that are often linked to OS and are considered associated factors influencing stroke pathology. Finally, we discuss the current pharmaceutics/therapeutics available for treating several cerebrovascular diseases.


Assuntos
Transtornos Cerebrovasculares , Hipertensão , Doenças Neurodegenerativas , Acidente Vascular Cerebral , Humanos , Estresse Oxidativo
4.
Int J Mol Sci ; 23(17)2022 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-36076944

RESUMO

Alzheimer's disease (AD) is the most common age-related dementia. The alteration in metabolic characteristics determines the prognosis. Patients at risk show reduced glucose uptake in the brain. Additionally, type 2 diabetes mellitus increases the risk of AD with increasing age. Therefore, changes in glucose uptake in the cerebral cortex may predict the histopathological diagnosis of AD. The shifts in glucose uptake and metabolism, insulin resistance, oxidative stress, and abnormal autophagy advance the pathogenesis of AD syndrome. Here, we summarize the role of altered glucose metabolism in type 2 diabetes for AD prognosis. Additionally, we discuss diagnosis and potential pharmacological interventions for glucose metabolism defects in AD to encourage the development of novel therapeutic methods.


Assuntos
Doença de Alzheimer , Diabetes Mellitus Tipo 2 , Resistência à Insulina , Doença de Alzheimer/metabolismo , Encéfalo/metabolismo , Diabetes Mellitus Tipo 2/metabolismo , Glucose/metabolismo , Humanos
5.
Cancers (Basel) ; 14(11)2022 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-35681744

RESUMO

Studies in targeting metabolism in cancer cells have shown the flexibility of cells in reprogramming their pathways away from a given metabolic block. Such behavior prompts a combination drug approach in targeting cancer metabolism, as a single compound may not address the tumor intractability. Overall, mammalian target of rapamycin complex 1 (mTORC1) signaling has been implicated as enabling metabolic escape in the case of a glycolysis block. From a library of compounds, the tyrosine kinase inhibitor ponatinib was screened to provide optimal reduction in metabolic activity in the production of adenosine triphosphate (ATP), pyruvate, and lactate for multiple myeloma cells; however, these cells displayed increasing levels of oxidative phosphorylation (OXPHOS), enabling them to continue generating ATP, although at a slower pace. The combination of ponatinib with the mTORC1 inhibitor, sirolimus, blocked OXPHOS; an effect also manifested in activity reductions for hexokinase 2 (HK2) and glucose-6-phosphate isomerase (GPI) glycolysis enzymes. There were also remarkably higher levels of reactive oxygen species (ROS) produced in mouse xenografts, on par with increased glycolytic block. The combination of ponatinib and sirolimus resulted in synergistic inhibition of tumor xenografts with no overt toxicity in treated mice for kidney and liver function or maintaining weight.

6.
Mol Cells ; 45(8): 588-602, 2022 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-35754370

RESUMO

Various RNA-binding proteins (RBPs) are key components in RNA metabolism and contribute to several neurodevelop-mental disorders. To date, only a few of such RBPs have been characterized for their roles in neocortex development. Here, we show that the RBP, Rbms1, is required for radial migration, polarization and differentiation of neuronal progenitors to neurons in the neocortex development. Rbms1 expression is highest in the early development in the developing cortex, with its expression gradually diminishing from embryonic day 13.5 (E13.5) to postnatal day 0 (P0). From in utero electroporation (IUE) experiments when Rbms1 levels are knocked down in neuronal progenitors, their transition from multipolar to bipolar state is delayed and this is accompanied by a delay in radial migration of these cells. Reduced Rbms1 levels in vivo also reduces differentiation as evidenced by a decrease in levels of several differentiation markers, meanwhile having no significant effects on proliferation and cell cycle rates of these cells. As an RNA binding protein, we profiled the RNA binders of Rbms1 by a cross-linked-RIP sequencing assay, followed by quantitative real-time polymerase chain reaction verification and showed that Rbms1 binds and stabilizes the mRNA for Efr3a, a signaling adapter protein. We also demonstrate that ectopic Efr3a can recover the cells from the migration defects due to loss of Rbms1, both in vivo and in vitro migration assays with cultured cells. These imply that one of the functions of Rbms1 involves the stabilization of Efr3a RNA message, required for migration and maturation of neuronal progenitors in radial migration in the developing neocortex.


Assuntos
Neocórtex , Animais , Movimento Celular , Proteínas de Ligação a DNA/metabolismo , Humanos , Camundongos , Neocórtex/metabolismo , Neurogênese , Neurônios/metabolismo , RNA/metabolismo , Proteínas de Ligação a RNA/genética , Proteínas de Ligação a RNA/metabolismo
7.
Biomed Pharmacother ; 150: 113032, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35486977

RESUMO

In MYCN-amplified neuroblastoma (NB), we noticed that the single compound treatment with the HDAC inhibitor vorinostat led to a reprogramming of the glycolytic pathway in these cells. This reprogramming was upregulation of fatty acid oxidation (FAO) and oxidative phosphorylation (OXPHOS), allowing the cells to generate ATP, albeit at a reduced rate. This behavior was dependent on reduced levels of MYCN and a corresponding increase in the levels of PPARD transcription factors. By integrating metabolic and functional studies in NB cells and mouse xenografts, we demonstrate a compensatory upregulation of FAO/OXPHOS metabolism that promotes resistance to HDAC inhibitors. From the additional compounds that could reverse this metabolic reprogramming, the mTORC1 inhibitor sirolimus was selected. Besides both a block of glycolysis and OXPHOS, the HDAC/mTORC1 inhibitor combination produced significantly higher levels of reactive oxygen species (ROS) in the treated cells and in xenograft tumor samples, also a consequence of increased glycolytic block. The lead compounds were also tested for changes in the message levels of the glycolytic enzymes and their pathway activity, and HK2 and GPI glycolytic enzymes were most affected at their RNA message level. This combination was seen with no overall toxicity in treated mice in terms of weight loss or liver/kidney function.


Assuntos
Inibidores de Histona Desacetilases , Neuroblastoma , Animais , Linhagem Celular Tumoral , Inibidores de Histona Desacetilases/farmacologia , Humanos , Alvo Mecanístico do Complexo 1 de Rapamicina , Camundongos , Proteína Proto-Oncogênica N-Myc/genética , Neuroblastoma/tratamento farmacológico , Neuroblastoma/genética , Neuroblastoma/metabolismo
9.
J Exp Clin Cancer Res ; 41(1): 18, 2022 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-35012594

RESUMO

BACKGROUND: Neuronal-origin HuD (ELAVL4) is an RNA binding protein overexpressed in neuroblastoma (NB) and certain other cancers. The RNA targets of this RNA binding protein in neuroblastoma cells and their role in promoting cancer survival have been unexplored. In the study of modulators of mTORC1 activity under the conditions of optimal cell growth and starvation, the role of HuD and its two substrates were studied. METHODS: RNA immunoprecipitation/sequencing (RIP-SEQ) coupled with quantitative real-time PCR were used to identify substrates of HuD in NB cells. Validation of the two RNA targets of HuD was via reverse capture of HuD by synthetic RNA oligoes from cell lysates and binding of RNA to recombinant forms of HuD in the cell and outside of the cell. Further analysis was via RNA transcriptome analysis of HuD silencing in the test cells. RESULTS: In response to stress, HuD was found to dampen mTORC1 activity and allow the cell to upregulate its autophagy levels by suppressing mTORC1 activity. Among mRNA substrates regulated cell-wide by HuD, GRB-10 and ARL6IP1 were found to carry out critical functions for survival of the cells under stress. GRB-10 was involved in blocking mTORC1 activity by disrupting Raptor-mTOR kinase interaction. Reduced mTORC1 activity allowed lifting of autophagy levels in the cells required for increased survival. In addition, ARL6IP1, an apoptotic regulator in the ER membrane, was found to promote cell survival by negative regulation of apoptosis. As a therapeutic target, knockdown of HuD in two xenograft models of NB led to a block in tumor growth, confirming its importance for viability of the tumor cells. Cell-wide RNA messages of these two HuD substrates and HuD and mTORC1 marker of activity significantly correlated in NB patient populations and in mouse xenografts. CONCLUSIONS: HuD is seen as a novel means of promoting stress survival in this cancer type by downregulating mTORC1 activity and negatively regulating apoptosis.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Proteína Semelhante a ELAV 4/genética , Alvo Mecanístico do Complexo 1 de Rapamicina/metabolismo , Proteínas de Membrana/metabolismo , Proteínas de Ligação a RNA/genética , Animais , Autofagia , Humanos , Masculino , Camundongos , Camundongos Nus , Transfecção
10.
Int J Mol Sci ; 22(22)2021 Nov 19.
Artigo em Inglês | MEDLINE | ID: mdl-34830376

RESUMO

Fungicides often cause genotoxic stress and neurodevelopmental disorders such as autism (ASD). Fungicide-azoxystrobin (AZOX) showed acute and chronic toxicity to various organisms, and remained a concern for ill effects in developing neurons. We evaluated the neurotoxicity of AZOX in developing mouse brains, and observed prenatal exposure to AZOX reduced neuronal viability, neurite outgrowth, and cortical migration process in developing brains. The 50% inhibitory concentration (IC50) of AZOX for acute (24 h) and chronic (7 days) exposures were 30 and 10 µM, respectively. Loss in viability was due to the accumulation of reactive oxygen species (ROS), and inhibited neurite outgrowth was due to the deactivation of mTORC1 kinase activity. Pretreatment with ROS scavenger- N-acetylcysteine (NAC) reserved the viability loss and forced activation of mTORC1 kinase revived the neurite outgrowth in AZOX treated neurons. Intra-amniotic injection of AZOX coupled with in utero electroporation of GFP-labelled plasmid in E15.5 mouse was performed and 20 mg/kg AZOX inhibited radial neuronal migration. Moreover, the accumulation of mitochondria was significantly reduced in AZOX treated primary neurons, indicative of mitochondrial deactivation and induction of apoptosis, which was quantified by Bcl2/Bax ratio and caspase 3 cleavage assay. This study elucidated the neurotoxicity of AZOX and explained the possible cure from it.


Assuntos
Apoptose/efeitos dos fármacos , Neurogênese/efeitos dos fármacos , Neurônios/efeitos dos fármacos , Pirimidinas/farmacologia , Estrobilurinas/farmacologia , Acetilcisteína/farmacologia , Animais , Transtorno Autístico/induzido quimicamente , Transtorno Autístico/genética , Transtorno Autístico/patologia , Movimento Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Feminino , Fungicidas Industriais/toxicidade , Humanos , Alvo Mecanístico do Complexo 1 de Rapamicina/genética , Camundongos , Mitocôndrias/efeitos dos fármacos , Crescimento Neuronal/efeitos dos fármacos , Neurônios/patologia , Gravidez , Efeitos Tardios da Exposição Pré-Natal , Pirimidinas/toxicidade , Espécies Reativas de Oxigênio/antagonistas & inibidores , Estrobilurinas/toxicidade
11.
Pharmazie ; 75(8): 395-400, 2020 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-32758340

RESUMO

It has been shown that Acori tatarinowii rhizoma (ATR) extract can improve cognitive functions in Alzheimer Diseas (AD) patients or animal models. In this study, we have examined the activity of ATR in 3×Tg-AD model mice with different comprehensive behavioral tests like the Morris water maze and Y-maze test assay for behavior. Moreover, we performed LFB staining for myelin determination in the AD model mouse. By analyzing different pathways, we determined key proteins that are beneficial for ameliorating AD syndrome in the mouse. Periluminally, ATR treatment improved the learning and memory ability that was determined by comprehensive behavioral tests. Moreover, treatment reduces the p-Tau accumulation in the 3×Tg-AD mouse and the level of p-Tau accumulation was at per with the wildtype control mouse and improves the myelin lining in 3×Tg-AD mouse. In conclusion, our results indicate that ATR-treatment can improve the learning ability of AD model mice and the hyperphosphorylation of Tau protein was decreased. ATR can protect myelin lining from damage in AD syndrome.


Assuntos
Doença de Alzheimer/tratamento farmacológico , Comportamento Animal/efeitos dos fármacos , Medicamentos de Ervas Chinesas/farmacologia , Bainha de Mielina/efeitos dos fármacos , Doença de Alzheimer/fisiopatologia , Animais , Modelos Animais de Doenças , Aprendizagem/efeitos dos fármacos , Masculino , Aprendizagem em Labirinto , Camundongos , Camundongos Transgênicos , Bainha de Mielina/patologia , Fosforilação , Rizoma , Proteínas tau/metabolismo
12.
Anim Cells Syst (Seoul) ; 24(2): 114-123, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32489691

RESUMO

In utero electroporation (IUE) is a useful technique for gene delivery in embryonic mouse brain. IUE technique is used to investigate the mammalian brain development in vivo. However, according to recent studies, IUE methodology has some limitations like the formation of artificial ectopias and heterotopias at the micro-injection site. Thus far, the artificial heterotopias generated by physical trauma during IUE are rarely reported. Here, we reported the artificial heterotopias and ectopias generated from surgical damages of micropipette in detail, and moreover, we described the protocol to avoid these phenotypes. For the experimental purpose, we transferred empty plasmids (pCAGIG-GFP) with green fluorescent-labelled protein into the cortical cortex by IUE and then compared the structure of the cortex region between the injected and un-injected cerebral hemispheres. The coronary section showed that ectopias and heterotopias were appeared on imperfect-injected brains, and layer maker staining, which including Ctip2 and TBR1 and laminin, can differentiate the physical damage, revealing the neurons in artificial ectopic and heterotopic area were not properly arranged. Moreover, premature differentiation of neurons in ectopias and heterotopias were observed. To avoid heterotopias and ectopias, we carefully manipulated the method of IUE application. Thus, this study might be helpful for the in utero electroporator to distinguish the artificial ectopias and heterotopias that caused by the physical injury by microneedle and the ways to avoid those undesirable circumstances.

13.
Cell Physiol Biochem ; 53(1): 258-280, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31313541

RESUMO

BACKGROUND/AIMS: Although neuroblastoma is a heterogeneous cancer, a substantial portion overexpresses CD71 (transferrin receptor 1) and MYCN. This study provides a mechanistically driven rationale for a combination therapy targeting neuroblastomas that doubly overexpress or have amplified CD71 and MYCN. For this subset, CD71 was targeted by its natural ligand, gambogic acid (GA), and MYCN was targeted with an HDAC inhibitor, vorinostat. A combination of GA and vorinostat was then tested for efficacy in cancer and non-cancer cells. METHODS: Microarray analysis of cohorts of neuroblastoma patients indicated a subset of neuroblastomas overexpressing both CD71 and MYCN. The viability with proliferation changes were measured by MTT and colony formation assays in neuroblastoma cells. Transfection with CD71 or MYCN along with quantitative real-time polymerase chain reaction (qRT-PCR) and Western blotting were used to detect expression changes. For pathway analysis, gene ontology (GO) and Protein-protein interaction analyses were performed to evaluate the potential mechanisms of GA and vorinostat in treated cells. RESULTS: For both GA and vorinostat, their pathways were explored for specificity and dependence on their targets for efficacy. For GA-treated cells, the viability/proliferation loss due to GA was dependent on the expression of CD71 and involved activation of caspase-3 and degradation of EGFR. It relied on the JNK-IRE1-mTORC1 pathway. The drug vorinostat also reduced cell viability/proliferation in the treated cells and this was dependent on the presence of MYCN as MYCN siRNA transfection led to a blunting of vorinostat efficacy and conversely, MYCN overexpression improved the vorinostat potency in those cells. Vorinostat inhibition of MYCN led to an increase of the pro-apoptotic miR183 levels and this, in turn, reduced the viability/proliferation of these cells. The combination treatment with GA and vorinostat synergistically reduced cell survival in the MYCN and CD71 overexpressing tumor cells. The same treatment had no effect or minimal effect on HEK293 and HEF cells used as models of non-cancer cells. CONCLUSION: A combination therapy with GA and vorinostat may be suitable for MYCN and CD71 overexpressing neuroblastomas.


Assuntos
Antígenos CD , Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Sistemas de Liberação de Medicamentos , Proteína Proto-Oncogênica N-Myc , Neuroblastoma , Receptores da Transferrina , Antígenos CD/genética , Antígenos CD/metabolismo , Caspase 3/genética , Caspase 3/metabolismo , Células HEK293 , Humanos , MicroRNAs/biossíntese , MicroRNAs/genética , Proteína Proto-Oncogênica N-Myc/antagonistas & inibidores , Proteína Proto-Oncogênica N-Myc/genética , Proteína Proto-Oncogênica N-Myc/metabolismo , Neuroblastoma/tratamento farmacológico , Neuroblastoma/genética , Neuroblastoma/metabolismo , Neuroblastoma/patologia , RNA Neoplásico/biossíntese , RNA Neoplásico/genética , Receptores da Transferrina/antagonistas & inibidores , Receptores da Transferrina/genética , Receptores da Transferrina/metabolismo , Vorinostat/farmacologia , Xantonas/farmacologia
14.
Exp Neurobiol ; 28(1): 54-61, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30853824

RESUMO

Scratching is a main behavioral response accompanied by acute and chronic itch conditions, and has been quantified as an objective correlate to assess itch in studies using laboratory animals. Scratching has been counted mostly by human annotators, which is a time-consuming and laborious process. It has been attempted to develop automated scoring methods using various strategies, but they often require specialized equipment, costly software, or implantation of device which may disturb animal behaviors. To complement limitations of those methods, we have adapted machine learning-based strategy to develop a novel automated and real-time method detecting mouse scratching from experimental movies captured using monochrome cameras such as a webcam. Scratching is identified by characteristic changes in pixels, body position, and body size by frame as well as the size of body. To build a training model, a novel two-step J48 decision tree-inducing algorithm along with a C4.5 post-pruning algorithm was applied to three 30-min video recordings in which a mouse exhibits scratching following an intradermal injection of a pruritogen, and the resultant frames were then used for the next round of training. The trained method exhibited, on average, a sensitivity and specificity of 95.19% and 92.96%, respectively, in a performance test with five new recordings. This result suggests that it can be used as a non-invasive, automated and objective tool to measure mouse scratching from video recordings captured in general experimental settings, permitting rapid and accurate analysis of scratching for preclinical studies and high throughput drug screening.

15.
Neuroscience ; 355: 126-140, 2017 07 04.
Artigo em Inglês | MEDLINE | ID: mdl-28501506

RESUMO

Brain developmental disorders such as lissencephaly can result from faulty neuronal migration and differentiation during the formation of the mammalian neocortex. The cerebral cortex is a modular structure, where developmentally, newborn neurons are generated as a neuro-epithelial sheet and subsequently differentiate, migrate and organize into their final positions in the cerebral cortical plate via a process involving both tangential and radial migration. The specific role of Mest, an imprinted gene, in neuronal migration has not been previously studied. In this work, we reduced expression of Mest with in utero electroporation of neuronal progenitors in the developing embryonic mouse neocortex. Reduction of Mest levels by shRNA significantly reduced the number of neurons migrating to the cortical plate. Also, Mest-knockdown disrupted the transition of bipolar neurons into multipolar neurons migrating out of the sub-ventricular zone region. The migrating neurons also adopted a more tangential migration pattern upon knockdown of the Mest message, losing their potential to attach to radial glia cells, required for radial migration. The differentiation and migration properties of neurons via Wnt-Akt signaling were affected by Mest changes. In addition, miR-335, encoded in a Mest gene intron, was identified as being responsible for blocking the default tangential migration of the neurons. Our results suggest that Mest and its intron product, miR-335, play important roles in neuronal migration with Mest regulating the morphological transition of primary neurons required in the formation of the mammalian neocortex.


Assuntos
Movimento Celular/genética , Regulação da Expressão Gênica no Desenvolvimento/fisiologia , Neocórtex/metabolismo , Neurônios/classificação , Neurônios/fisiologia , Proteínas/metabolismo , Animais , Animais Recém-Nascidos , Caderinas/metabolismo , Embrião de Mamíferos , Regulação da Expressão Gênica no Desenvolvimento/genética , Proteínas de Fluorescência Verde/genética , Proteínas de Fluorescência Verde/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , MicroRNAs/genética , MicroRNAs/metabolismo , Proteínas Associadas aos Microtúbulos/metabolismo , Neocórtex/citologia , Neocórtex/embriologia , Neocórtex/crescimento & desenvolvimento , Nestina/metabolismo , Neuroblastoma/patologia , Neurogênese/genética , Proteínas/genética , RNA Mensageiro/metabolismo , RNA Interferente Pequeno/genética , RNA Interferente Pequeno/metabolismo , Fatores de Tempo , Transdução Genética , Transfecção , Proteínas tau/metabolismo
16.
Biochim Biophys Acta Gen Subj ; 1861(2): 23-36, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27815218

RESUMO

BACKGROUND: Drug resistance from apoptosis is a challenging issue with different cancer types, and there is an interest in identifying other means of inducing cytotoxicity. Here, treatment of neuroblastoma cells with oxyresveratrol (OXYRES), a natural antioxidant, led to dose-dependent cell death and increased autophagic flux along with activation of caspase-dependent apoptosis. METHODS: For cell viability, we performed the CCK-8 assay. Protein expression changes were with Western blot and immunocytochemistry. Silencing of proteins was with siRNA. The readouts for cell cycle, mitochondria membrane potential, caspase-3, autophagy and apoptosis were performed with flow cytometry. RESULTS: Phosphorylation of p38 MAPK increased with OXYRES treatment and inhibition of p38 reduced autophagy and cell death from OXYRES. In contrast, PI3K/AKT/mTOR signaling decreased in the target cells with OXYRES and inhibition of PI3K or mTOR enhanced OXYRES-mediated cytotoxicity with increased levels of autophagy. Modulation of either of the apoptosis and autophagy flux pathways affected the extent of cell death by OXYRES, but did not affect the indicators of these pathways with respect to each other. Both pathways were independent of ROS generation or p53 activation. CONCLUSION: OXYRES led to cell death from autophagy, which was independent of apoptosis induction. The OXYRES effects were due to changes in the activity levels of p38 MAPK and PI3K/AKT/mTOR. GENERAL SIGNIFICANCE: With two independent and parallel pathways for cytotoxicity induction in target cells, this study puts forward a potential utility for OXYRES or the pathways it represents as novel means of inducing cell death in neuroblastoma cells.


Assuntos
Apoptose/efeitos dos fármacos , Autofagia/efeitos dos fármacos , Neuroblastoma/tratamento farmacológico , Extratos Vegetais/farmacologia , Transdução de Sinais/efeitos dos fármacos , Estilbenos/farmacologia , Animais , Proteínas Reguladoras de Apoptose/metabolismo , Caspase 3/metabolismo , Linhagem Celular , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Células HEK293 , Humanos , Neuroblastoma/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Fosforilação/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-akt/metabolismo , Ratos , Espécies Reativas de Oxigênio/metabolismo , Serina-Treonina Quinases TOR/metabolismo , Proteína Supressora de Tumor p53/metabolismo , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo
17.
Biochem Pharmacol ; 117: 97-112, 2016 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-27520483

RESUMO

18α-Glycyrrhetinic acid (18-GA) is a known gap-junction inhibitor with demonstrated anticancer effects. However, the different modes of cell cytotoxicity for 18-GA remain to be characterized. In this study, 18-GA reduced the expression of cell-cell interaction proteins (N- and VE-cadherin), and led to a dose-dependent increase in cytotoxicity of the neuroblastoma cells tested, but was less toxic toward actively dividing human embryonic kidney cells. We found that 18-GA could induce both autophagy and apoptosis. 18-GA mediated autophagy was due to accumulation of Atg5, Atg7 and LC3II and degradation of p62. Individual siRNAs against Atg5 and Atg7 prevented autophagy and resulted in a further loss of viability with 18-GA. In addition, combination of 18-GA with autophagy inhibitor chloroquine produced a more significant cell death. This implied a pro-survival function for autophagy induction with 18-GA. 18-GA also led to the destabilization of Bcl-2/Beclin-1 interaction and cleavage of Beclin-1, a protein known to play role in apoptosis and autophagy induction. Treatment of cells by a pan-caspase inhibitor or a caspase-3 siRNA prevented a large portion of 18-GA mediated cytotoxicity, demonstrating that caspase-dependent apoptosis induction was responsible for most of the observed cytotoxicity. In terms of signaling, 18-GA led to reduced phosphorylation of all three classes of MAP kinases. Taken together, 18-GA or its pathways may lead to more effective, targeted therapeutics against neuroblastoma.


Assuntos
Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Proteína Beclina-1/metabolismo , Ácido Glicirretínico/análogos & derivados , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Neuroblastoma/tratamento farmacológico , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Animais , Antineoplásicos/efeitos adversos , Autofagia/efeitos dos fármacos , Proteína Beclina-1/antagonistas & inibidores , Proteína Beclina-1/genética , Caderinas/antagonistas & inibidores , Caderinas/genética , Caderinas/metabolismo , Linhagem Celular Tumoral , Forma Celular/efeitos dos fármacos , Tamanho Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Ácido Glicirretínico/efeitos adversos , Ácido Glicirretínico/farmacologia , Células HEK293 , Humanos , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Neuroblastoma/metabolismo , Neuroblastoma/patologia , Fosforilação/efeitos dos fármacos , Processamento de Proteína Pós-Traducional/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-bcl-2/antagonistas & inibidores , Proteínas Proto-Oncogênicas c-bcl-2/genética , Interferência de RNA , Ratos
18.
Mol Cells ; 39(2): 119-28, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26674967

RESUMO

Angelica polymorpha Maxim root extract (APRE) is a popular herbal medicine used for treating stomachache, abdominal pain, stomach ulcers, and rheumatism; however the effect of APRE on cancer cells has not yet been explored. Here, we examined APRE cytotoxicity seen on target neuroblastoma cells (NB) using cell viability assays, DAPI visualization of fragmented DNA, and Western blotting analysis of candidate signaling pathways involved in proliferation and apoptosis. We demonstrated that APRE reduced cell viability in NB to a greater extent than in fibroblast cells. In addition, we found that APRE could inhibit the three classes of MAPK proteins and could also down-regulate the PI3K/AKT/GSK-3ß activity all being relevant for proliferation and survival. APRE could also up-regulate Bax expression and down-regulate Bcl-2 and Mcl-1. With APRE treatment, depolarization of mitochondria membrane potential and activation of caspase-3 was demonstrated in the SH-SY5Y cells. We could not found increased activity of death receptor and caspase-8 as markers of the extrinsic apoptosis pathway for the APRE treated cells. In presence of a caspase-3 siRNA and a pan-caspase inhibitor, APRE could not reduce the viability of NB cells to a significant degree. So we predicted that with APRE, the intrinsic pathway was solely responsible for inducing apoptosis as we also showed that the non-caspase autophagy pathway or ER stress-ROS mediated pathways were not involved. These findings demonstrate that an intrinsic mitochondria-mediated apoptosis pathway mediates the apoptotic effects of APRE on SH-SY5Y cells, and that APRE shows promise as a novel agent for neuroblastoma therapy.


Assuntos
Angelica/química , Antineoplásicos Fitogênicos/farmacologia , Apoptose/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica , Neurônios/efeitos dos fármacos , Extratos Vegetais/farmacologia , Antineoplásicos Fitogênicos/isolamento & purificação , Autofagia/efeitos dos fármacos , Caspase 3/genética , Caspase 3/metabolismo , Caspase 8/genética , Caspase 8/metabolismo , Linhagem Celular , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Fragmentação do DNA/efeitos dos fármacos , Fibroblastos/citologia , Fibroblastos/efeitos dos fármacos , Fibroblastos/metabolismo , Quinase 3 da Glicogênio Sintase/genética , Quinase 3 da Glicogênio Sintase/metabolismo , Glicogênio Sintase Quinase 3 beta , Humanos , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Proteína de Sequência 1 de Leucemia de Células Mieloides/genética , Proteína de Sequência 1 de Leucemia de Células Mieloides/metabolismo , Neurônios/metabolismo , Neurônios/patologia , Fosfatidilinositol 3-Quinases/genética , Fosfatidilinositol 3-Quinases/metabolismo , Extratos Vegetais/química , Raízes de Plantas/química , Proteínas Proto-Oncogênicas c-akt/genética , Proteínas Proto-Oncogênicas c-akt/metabolismo , Proteínas Proto-Oncogênicas c-bcl-2/genética , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Transdução de Sinais , Proteína X Associada a bcl-2/genética , Proteína X Associada a bcl-2/metabolismo
19.
J Pharmacopuncture ; 18(3): 32-41, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26389000

RESUMO

OBJECTIVES: Condurango (Gonolobus condurango) extract is used by complementary and alternative medicine (CAM) practitioners as a traditional medicine, including homeopathy, mainly for the treatment of syphilis. Condurango bark extract is also known to reduce tumor volume, but the underlying molecular mechanisms still remain unclear. METHODS: Using a cervical cancer cell line (HeLa) as our model, the molecular events behind condurango extract's (CE's) anticancer effect were investigated by using flow cytometry, immunoblotting and reverse transcriptase-polymerase chain reaction (RT-PCR). Other included cell types were prostate cancer cells (PC3), transformed liver cells (WRL-68), and peripheral blood mononuclear cells (PBMCs). RESULTS: Condurango extract (CE) was found to be cytotoxic against target cells, and this was significantly deactivated in the presence of N-acetyl cysteine (NAC), a scavenger of reactive oxygen species (ROS), suggesting that its action could be mediated through ROS generation. CE caused an increase in the HeLa cell population containing deoxyribonucleic acid (DNA) damage at the G zero/Growth 1 (G0/G1) stage. Further, CE increased the tumor necrosis factor alpha (TNF-α) and the fas receptor (FasR) levels both at the ribonucleic acid (RNA) and the protein levels, indicating that CE might have a cytotoxic mechanism of action. CE also triggered a sharp decrease in the expression of nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB ) both at the RNA and the protein levels, a possible route to attenuation of B-cell lymphoma 2 (Bcl-2), and caused an opening of the mitochondrial membrane's permeability transition (MPT) pores, thus enhancing caspase activities. CONCLUSION: Overall, our results suggest possible pathways for CE mediated cytotoxicity in model cancer cells.

20.
Nutr Res ; 35(10): 921-929, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26319614

RESUMO

Probiotic treatment has been gaining attention due to its remarkable effects in alleviating toxicity and carcinogenesis. The novel strain Pediococcus pentosaceus GS4 has been reported for probiotic, survivability in simulated gastrointestinal fluid, and antioxidative and biohydrogenation properties. Therefore, we hypothesize that this specific strain might be able to assuage the effect of azoxymethane (AOM)-induced toxicity in mice. Twenty-eight Swiss albino mice were divided into 4 groups and were studied for 32 weeks. Azoxymethane (10 mg/kg body weight) was administered intraperitoneally twice (0th and 14th days), and probiotic GS4 (1.1 × 10(9) colony-forming unit/mL) was given orally for the respective groups. Mice who served as the normal control received only normal saline. GS4-intervened AOM-induced mice showed marked improvement at the histopathologic level, in the liver and kidney. Moreover, probiotic GS4 intervention in AOM-induced mice exhibited a significant reduction in the liver function biomarker when compared with the AOM-induced mice. Probiotic GS4 intervention reduced the intestinal structural deformities as evident from the elevated brush border membrane-associated disaccharidases (sucrase, lactase) and intestinal alkaline phosphatase activities, which were found disrupted by AOM intoxication. Fecal bacterial load was found to be reduced in AOM-induced mice which were subsequently replenished by the probiotic GS4 intervention as apparent from the enhanced fecal bacterial load. There were no adverse effects observed in the probiotic control group. Conclusively, novel probiotic strain GS4 exhibited safe and beneficial effects against the toxicity threats posed by AOM. Thus, GS4 could be considered as a potential food supplement/additive for therapeutic purposes in gastrointestinal disorders related to inflammation and cancer.


Assuntos
Azoximetano/toxicidade , Pediococcus/fisiologia , Probióticos/uso terapêutico , Fosfatase Alcalina/metabolismo , Animais , Azoximetano/administração & dosagem , Doença Hepática Induzida por Substâncias e Drogas/prevenção & controle , Microbioma Gastrointestinal/efeitos dos fármacos , Microbioma Gastrointestinal/fisiologia , Intestinos/enzimologia , Nefropatias/induzido quimicamente , Nefropatias/prevenção & controle , Lactase/metabolismo , Camundongos , Peritônio/efeitos dos fármacos , Sacarase/metabolismo
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