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1.
J Biol Chem ; 290(8): 4994-5006, 2015 Feb 20.
Artículo en Inglés | MEDLINE | ID: mdl-25540201

RESUMEN

Myc is up-regulated in almost all cancer types and is the subject of intense investigation because of its pleiotropic effects controlling a broad spectrum of cell functions. However, despite its recognition as a stand-alone molecular target, development of suitable strategies to block its function is hindered because of its nonenzymatic nature. We reported earlier that arachidonate 5-lipoxygenase (5-Lox) plays an important role in the survival and growth of prostate cancer cells, although details of the underlying mechanisms have yet to be characterized. By whole genome gene expression array, we observed that inhibition of 5-Lox severely down-regulates the expression of c-Myc oncogene in prostate cancer cells. Moreover, inhibition of 5-Lox dramatically decreases the protein level, nuclear accumulation, DNA binding, and transcriptional activities of c-Myc. Both the 5-Lox inhibition-induced down-regulation of c-Myc and induction of apoptosis are mitigated when the cells are treated with 5-oxoeicosatetraenoic acid, a metabolite of 5-Lox, confirming a role of 5-Lox in these processes. c-Myc is a transforming oncogene widely expressed in prostate cancer cells and maintains their transformed phenotype. Interestingly, MK591, a specific 5-Lox inhibitor, strongly affects the viability of Myc-overactivated prostate cancer cells and completely blocks their invasive and soft agar colony-forming abilities, but it spares nontransformed cells where expression of 5-Lox is undetectable. These findings indicate that the oncogenic function of c-Myc in prostate cancer cells is regulated by 5-Lox activity, revealing a novel mechanism of 5-Lox action and suggesting that the oncogenic function of c-Myc can be suppressed by suitable inhibitors of 5-Lox.


Asunto(s)
Inhibidores de Proteína Activante de 5-Lipoxigenasa/farmacología , Apoptosis/efectos de los fármacos , Araquidonato 5-Lipooxigenasa/metabolismo , Indoles/farmacología , Neoplasias de la Próstata/enzimología , Proteínas Proto-Oncogénicas c-myc/biosíntesis , Quinolinas/farmacología , Transducción de Señal/efectos de los fármacos , Araquidonato 5-Lipooxigenasa/genética , Línea Celular Tumoral , Regulación hacia Abajo/efectos de los fármacos , Regulación hacia Abajo/genética , Regulación Enzimológica de la Expresión Génica/efectos de los fármacos , Regulación Enzimológica de la Expresión Génica/genética , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Regulación Neoplásica de la Expresión Génica/genética , Humanos , Inhibidores de la Lipooxigenasa/farmacología , Masculino , Neoplasias de la Próstata/tratamiento farmacológico , Neoplasias de la Próstata/genética , Neoplasias de la Próstata/patología , Proteínas Proto-Oncogénicas c-myc/genética , Transcripción Genética/efectos de los fármacos , Transcripción Genética/genética
2.
Org Biomol Chem ; 10(12): 2380-4, 2012 Mar 28.
Artículo en Inglés | MEDLINE | ID: mdl-22334308

RESUMEN

A highly selective and sensitive fluorescent Zn(2+) sensor, 2,6-bis(2-hydroxy-benzoic acid hydrazide)-4-methylphenol (1), was designed and synthesized. In aqueous THF (4 : 6 v/v) ligand 1 induces a 2 : 1 complex formation with respect to Zn(2+) at physiological pH. This probe features visible light excitation(390 nm) and emission (490 nm) profiles, excellent selectivity responses for Zn(2+)over other competing biological metal ions with K(d) < 1 pM(2), LOD < 1 ng L(-1) and about 680 fold enhancement in fluorescent intensity upon Zn(2+) binding. It also exhibits cell permeability and intracellular Zn(2+) sensing in A375 human melanoma cancer cell.


Asunto(s)
Colorantes Fluorescentes/química , Hidrazonas/química , Fenoles/química , Zinc/análisis , Línea Celular Tumoral , Colorantes Fluorescentes/análisis , Humanos , Hidrazonas/análisis , Modelos Moleculares , Estructura Molecular , Fenoles/análisis
3.
Zhong Xi Yi Jie He Xue Bao ; 10(2): 210-27, 2012 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-22313889

RESUMEN

OBJECTIVE: To examine if potentiated homeopathic drug Arsenicum Album 30C (Ars Alb 30C) can reduce sodium arsenite-induced toxicity in Escherichia coli. METHODS: E. coli were exposed to low arsenite insult after they grew up to log phase in standard Luria-Bertani medium. E. coli were treated with 1 or 2 mmol/L sodium arsenite alone (control), or Ars Alb 30C was added to the medium of a subset of sodium arsenite-treated bacteria (drug-treated), or homeopathically agitated alcohol was added to the medium containing a subset of sodium arsenite-treated bacteria (placebo-treated). A sub-set of untreated E. coli served as the negative control. Glucose uptake, specific activities of hexokinase, lipid peroxidase (LPO), superoxide dismutase (SOD) and catalase, intra- and extra-cellular sodium arsenite content, cell growth, cell membrane potential, DNA damage, intracellular reactive oxygen species (ROS), adenosine triphosphate (ATP) and free glutathione content and expressions of arsB and ptsG gene in normal control, sodium arsenite-treated, drug-treated and placebo-treated E. coli were analyzed. Treatments were blinded and randomized. RESULTS: In sodium arsenite-treated E. coli, glucose uptake, intracellular ROS, LPO and DNA damage increased along with decrease in the specific activities of hexokinase, SOD and catalase, intracellular ATP and free glutathione contents and cell membrane potential and growth, and there were increases in expression levels of arsB gene and ptsG gene. Ars Alb 30C administration reduced arsenic toxicity in E. coli by inhibiting generation of ROS and increasing tolerance to arsenite toxicity and cell growth. CONCLUSION: Ars Alb 30C ameliorated arsenic toxicity and DNA damage, validating efficacy of ultra-highly diluted remedies used in homeopathy.


Asunto(s)
Arsenicales/antagonistas & inhibidores , Arsenitos/toxicidad , Escherichia coli/efectos de los fármacos , Escherichia coli/metabolismo , Homeopatía , Especies Reactivas de Oxígeno/metabolismo , Daño del ADN , Regulación Bacteriana de la Expresión Génica/efectos de los fármacos , Peroxidación de Lípido , Regulación hacia Arriba
4.
Zhong Xi Yi Jie He Xue Bao ; 10(9): 1025-38, 2012 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-22979935

RESUMEN

OBJECTIVE: To evaluate the role of chelidonine isolated from ethanolic extract of Chelidonium majus in inducing apoptosis in HeLa cells and to assess the main signalling pathways involved. METHODS: Cells were initially treated with different concentrations of chelidonine for 48 h and the median lethal dose (LD50) value was selected by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay. Morphological analysis of nuclear condensation and DNA damage and fragmentation were measured by 4',6-diamidino-2-phenylindole staining and comet assay. Further, reactive oxygen species (ROS) generation, cell cycle arrest and change in mitochondrial membrane potential were also examined and analyzed by flow cytometry. Evaluation of interaction of drug with CT DNA was investigated by circular dichroism (CD) spectral analysis to find any possible drug-CT DNA interaction. The mRNA and protein expressions of major signal proteins like p38, p53, protein kinase B (AKT), phosphatidylinositol 3-kinases (PI3K), Janus kinase 3 (JAK3), signal transducer and activator of transcription 3 (STAT3) and E6 and E7 oncoproteins as well as the pro-apoptotic genes and antiapoptotic genes were also estimated by reverse transcriptase-polymerase chain reaction and Western blotting. RESULTS: Based on LD(50) value (30 µg/mL) of chelidonine, three doses were selected, namely, 22.5 µg/mL (D1), 30.0 µg/mL (D2) and 37.5 µg/mL (D3). Results showed that chelidonine inhibited proliferation and induced apoptosis in HeLa cells through generation of ROS, cell cycle arrest at sub-G1 and G0/G1 stage, change in mitochondrial membrane potential and fragmentation of DNA. Results of CD spectra showed effective interaction between chelidonine and calf thymus DNA. Studies of signalling pathway revealed that chelidonine could efficiently induce apoptosis through up-regulation of expressions of p38, p53 and other pro-apoptotic genes and down-regulation of expressions of AKT, PI3K, JAK3, STAT3, E6, E7 and other antiapoptotic genes. CONCLUSION: Chelidonine isolated from Chelidonium majus efficiently induced apoptosis in HeLa cells through possible alteration of p38-p53 and AKT/PI3 kinase signalling pathways.


Asunto(s)
Apoptosis/efectos de los fármacos , Benzofenantridinas/farmacología , Transducción de Señal/efectos de los fármacos , Benzofenantridinas/química , Puntos de Control del Ciclo Celular , Proliferación Celular/efectos de los fármacos , Chelidonium/química , Células HeLa , Humanos , Potencial de la Membrana Mitocondrial/efectos de los fármacos , Fosfatidilinositol 3-Quinasas/metabolismo , Proteínas Proto-Oncogénicas c-akt/metabolismo , Proteínas Proto-Oncogénicas c-bcl-2/metabolismo , Factor de Transcripción STAT3/metabolismo , Proteína p53 Supresora de Tumor/metabolismo , Proteínas Quinasas p38 Activadas por Mitógenos/metabolismo
5.
Life Sci ; 278: 119524, 2021 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-33887344

RESUMEN

The association of adiponectin with metabolism and cancer is well established. Since its discovery in 1990, adiponectin, as one of the adipose tissue-secreted adipokines, has been very widely studied in biomedical research. Low levels of circulatory adiponectin have been reported in obesity, inflammatory diseases and various types of cancers including colorectal cancer (CRC), which is highly linked with obesity and gut inflammation. However, the function and underlying mechanisms of adiponectin in CRC is not well understood. In addition, there are contradictory reports on the role of adiponectin in cancer. Therefore, further investigation is needed. In this review, we explore the information available on the relationship between adiponectin and CRC with respect to proliferation, cell survival, angiogenesis and inflammation. We also highlighted the knowledge gaps, filling in which could help us better understand the function and mechanisms of adiponectin in CRC.


Asunto(s)
Adiponectina/metabolismo , Neoplasias Colorrectales/metabolismo , Regulación Neoplásica de la Expresión Génica , Inflamación/metabolismo , Neovascularización Patológica , Adipoquinas/metabolismo , Tejido Adiposo/metabolismo , Animales , Biomarcadores de Tumor/metabolismo , Proliferación Celular , Supervivencia Celular , Humanos , Leptina/metabolismo , Ratones , Metástasis de la Neoplasia , Obesidad/metabolismo , Microambiente Tumoral
6.
Life Sci ; 262: 118507, 2020 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-33017572

RESUMEN

Nonalcoholic fatty liver disease (NAFLD) is one of the major metabolic diseases that occur in almost one in every four global population, while colorectal cancer (CRC) is one of the leading causes of cancer related deaths in the world. Individuals with pre-existing NAFLD show a higher rate of developing CRC and liver metastasis, suggesting a causal relationship. Interestingly, both of these diseases are strongly associated with obesity, which is also a growing global health concern. In this current review, we will explore scientific findings that demonstrate the relationship between NAFLD, CRC and obesity, as well as the underlying mechanisms. We will also indicate the missing links and knowledge gaps that require more in-depth investigation.


Asunto(s)
Neoplasias Colorrectales/patología , Enfermedad del Hígado Graso no Alcohólico/fisiopatología , Obesidad/complicaciones , Animales , Neoplasias Colorrectales/epidemiología , Neoplasias Colorrectales/etiología , Salud Global , Humanos , Enfermedad del Hígado Graso no Alcohólico/epidemiología , Enfermedad del Hígado Graso no Alcohólico/etiología , Obesidad/epidemiología , Factores de Riesgo
7.
Methods Mol Biol ; 1862: 245-250, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-30315472

RESUMEN

The obesity epidemic is a critical public health problem closely associated with the development of metabolic disease. In obesity there is excess white adipose tissue, a dynamic tissue that has many biological functions. Specifically visceral adipose tissue (VAT) is an active endocrine organ producing hormones that control systemic metabolism. VAT accumulates immune cells that produce cytokines that drive chronic inflammation and promote insulin resistance. VAT can be surgically removed in experimental animals (lipectomy) to explore mechanisms by which VAT participates in metabolic, endocrine, and immunological functions. This chapter describes the technical protocol for efficient and successful removal of the gonadal fat pads in mice.


Asunto(s)
Modelos Animales de Enfermedad , Grasa Intraabdominal/cirugía , Lipectomía/métodos , Obesidad/patología , Animales , Dieta Alta en Grasa/efectos adversos , Humanos , Grasa Intraabdominal/metabolismo , Lipectomía/instrumentación , Ratones , Obesidad/etiología , Obesidad/cirugía
8.
IEEE Trans Neural Netw ; 19(3): 381-96, 2008 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-18334359

RESUMEN

Suppose for a given classification or function approximation (FA) problem data are collected using l sensors. From the output of the ith sensor, ni features are extracted, thereby generating p = sigma li = 1 ni features, so for the task we have X subset Rp as input data along with their corresponding outputs or class labels Y subset Rc. Here, we propose two connectionist schemes that can simultaneously select the useful sensors and learn the relation between X and Y. One scheme is based on the radial basis function (RBF) network and the other uses the multilayered perceptron (MLP) network. Both schemes are shown to possess the universal approximation property. Simulations show that the methods can detect the bad/derogatory groups of features online and can eliminate the effect of these bad features while doing the FA or classification task.


Asunto(s)
Almacenamiento y Recuperación de la Información , Redes Neurales de la Computación , Procesamiento de Señales Asistido por Computador , Humanos , Sistemas de Información , Sistemas en Línea
9.
Adipocyte ; 7(1): 45-48, 2018 01 02.
Artículo en Inglés | MEDLINE | ID: mdl-29095087

RESUMEN

Although there is a growing number of incidences of obesity and obesity-linked cancers, how excess adiposity actually causes cancer has not been fully explained. Our previous study showed that removal of visceral adipose tissue significantly reduced the number of ultraviolet radiation (UVR)-initiated, high-fat diet-promoted skin cancers. This commentary focuses on our recently published study (Chakraborty, et al., 2017) which demonstrated that fibroblast growth factor-2 (FGF2) released from visceral adipose tissue is a key factor in the malignant transformation of epithelial cells. Within this commentary we have provided additional interpretations and new data in support of the role of FGF2 in adiposity-associated tumorigenesis.


Asunto(s)
Neoplasias de la Mama/metabolismo , Factor 2 de Crecimiento de Fibroblastos/metabolismo , Neoplasias Cutáneas/metabolismo , Tejido Adiposo/metabolismo , Adiposidad , Neoplasias de la Mama/etiología , Dieta Alta en Grasa/efectos adversos , Humanos , Grasa Intraabdominal , Obesidad/metabolismo , Transducción de Señal/efectos de los fármacos , Transducción de Señal/efectos de la radiación , Neoplasias Cutáneas/etiología , Rayos Ultravioleta/efectos adversos
10.
Adipocyte ; 7(2): 113-120, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29561195

RESUMEN

Obesity is a leading risk factor for post-menopausal breast cancer, and this is concerning as 40% of cancer diagnoses in 2014 were associated with overweight/obesity. Despite this epidemiological link, the underlying mechanism responsible is unknown. We recently published that visceral adipose tissue (VAT) releases FGF2 and stimulates the transformation of skin epithelial cells. Furthermore, obesity is differentially associated with many epithelial cancers, and this mechanistic link could be translational. As FGF2 and FGFR1 are implicated in breast cancer progression, we hypothesize that VAT-derived FGF2 plays a translational role in promoting adiposity-associated mammary epithelial cell transformation. In this brief report, data suggest that FGF2/FGFR1 signaling is a potential mechanistic link in VAT-stimulated transformation of breast epithelial cells.


Asunto(s)
Células Epiteliales/metabolismo , Transición Epitelial-Mesenquimal , Factor 2 de Crecimiento de Fibroblastos/metabolismo , Grasa Intraabdominal/metabolismo , Células Cultivadas , Humanos , Piel/metabolismo
11.
Cancer Prev Res (Phila) ; 11(3): 129-142, 2018 03.
Artículo en Inglés | MEDLINE | ID: mdl-29246955

RESUMEN

Almost half a million of all new cancers have been attributed to obesity and epidemiologic evidence implicates visceral adipose tissue (VAT) and high-fat diets (HFD) in increasing cancer risk. We demonstrated that VAT-derived fibroblast growth factor 2 (FGF2) from mice fed an HFD or obese individuals stimulates the malignant transformation of epithelial cells. Mechanism-based strategies to prevent this VAT-enhanced tumorigenesis have not been explored. Clinical studies have indicated that bromodomain inhibitors have considerable potential as therapeutic agents for cancer by inhibiting the activity of several oncogenes, including c-Myc; however, their chemopreventive activity is unknown. We show herein that mice with visceral adiposity have elevated nuclear c-Myc expression in their epidermis. We hypothesized that the bromodomain inhibitor I-BET-762 (I-BET) would have efficacy in the prevention of malignant transformation by VAT and FGF2. We tested this hypothesis using our novel models of VAT-stimulated transformation in vitro and FGF2- stimulated tumor formation in vivo We found that I-BET significantly attenuates VAT and FGF2-stimulated transformation and inhibits VAT-induced c-Myc protein expression in several skin and breast epithelial cell lines. Moreover, I-BET attenuated tumor growth significantly in FGF2-treated nude mice. Work is ongoing to determine the role of visceral adiposity in c-Myc activity in several tissues and determine the inhibitory effect of I-BET on VAT-promoted tumors in vivoCancer Prev Res; 11(3); 129-42. ©2017 AACRSee related editorial by Berger and Scacheri, p. 125.


Asunto(s)
Adiposidad/efectos de los fármacos , Adiposidad/fisiología , Antineoplásicos/farmacología , Benzodiazepinas/farmacología , Transformación Celular Neoplásica/efectos de los fármacos , Animales , Transformación Celular Neoplásica/genética , Células Cultivadas , Femenino , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Humanos , Grasa Intraabdominal/efectos de los fármacos , Grasa Intraabdominal/metabolismo , Ratones , Ratones Endogámicos BALB C , Ratones Desnudos , Neoplasias/etiología , Neoplasias/genética , Neoplasias/patología , Neoplasias/prevención & control , Obesidad/complicaciones , Obesidad/genética , Obesidad/patología , Proteínas/antagonistas & inhibidores , Proteínas Proto-Oncogénicas c-myc/genética , Ensayos Antitumor por Modelo de Xenoinjerto
12.
IEEE Trans Neural Netw ; 15(1): 110-23, 2004 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-15387252

RESUMEN

Most methods of classification either ignore feature analysis or do it in a separate phase, offline prior to the main classification task. This paper proposes a neuro-fuzzy scheme for designing a classifier along with feature selection. It is a four-layered feed-forward network for realizing a fuzzy rule-based classifier. The network is trained by error backpropagation in three phases. In the first phase, the network learns the important features and the classification rules. In the subsequent phases, the network is pruned to an "optimal" architecture that represents an "optimal" set of rules. Pruning is found to drastically reduce the size of the network without degrading the performance. The pruned network is further tuned to improve performance. The rules learned by the network can be easily read from the network. The system is tested on both synthetic and real data sets and found to perform quite well.


Asunto(s)
Lógica Difusa , Redes Neurales de la Computación
13.
Integr Cancer Ther ; 12(5): 433-41, 2013 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-23615751

RESUMEN

OBJECTIVE: Ethanolic extract of Gymnema sylvestre (GS) leaves is used as a potent antidiabetic drug in various systems of alternative medicine, including homeopathy. The present study was aimed at examining if GS also had anticancer potentials, and if it had, to elucidate its possible mechanism of action. METHODS: We initially tested possible anticancer potential of GS on A375 cells (human skin melanoma) through MTT assay and determined cytotoxicity levels in A375 and normal liver cells; we then thoroughly studied its apoptotic effects on A375 cells through protocols such as Hoechst 33258, H2DCFDA, and rhodamine 123 staining and conducted ELISA for cytochrome c, caspase 3, and PARP activity levels; we determined the mRNA level expression of cytochrome c, caspase 3, Bcl2, Bax, PARP, ICAD, and EGFR signaling genes through semiquantitative reverse transcriptase polymerase chain reaction and conducted Western blot analysis of caspase 3 and PARP. We also analyzed cell cycle events, determined reactive oxygen species accumulation, measured annexin V-FITC/PI and rhodamine 123 intensity by flow cytometry. RESULTS: Compared with both normal liver cells and drug-untreated A375, the mortality of GS-treated A375 cells increased in a dose-dependent manner. Additionally, GS induced nuclear DNA fragmentation and showed an increased level of mRNA expression of apoptotic signal related genes cytochrome c, caspase 3, PARP, Bax, and reduced expression level of ICAD, EGFR, and the anti-apoptotic gene Bcl2. CONCLUSION: Overall results indicate GS to have significant anticancer effect on A375 cells apart from its reported antidiabetic effect, indicating possibility of its palliative use in patients with symptoms of both the diseases.


Asunto(s)
Antineoplásicos/farmacología , Caspasa 3/metabolismo , Gymnema sylvestre , Melanoma/patología , Extractos Vegetales/farmacología , Especies Reactivas de Oxígeno/metabolismo , Neoplasias Cutáneas/patología , Supervivencia Celular/efectos de los fármacos , Células Cultivadas , Evaluación Preclínica de Medicamentos , Humanos , Hipoglucemiantes/farmacología , Melanoma/metabolismo , Mitocondrias/efectos de los fármacos , Mitocondrias/metabolismo , Transducción de Señal/efectos de los fármacos , Neoplasias Cutáneas/metabolismo
14.
Eur J Pharmacol ; 698(1-3): 110-21, 2013 Jan 05.
Artículo en Inglés | MEDLINE | ID: mdl-23142370

RESUMEN

When the prostate cancer cells become unresponsive to androgen therapy, resistance to chemotherapy becomes imminent, resulting in high mortality. To combat this situation, lycopodine, a pharmacologically important bioactive component derived from Lycopodium clavatum spores, was tested against hormone sensitive (LnCaP) and refractory (PC3) prostate cancer cells in vitro. This study aims to check if lycopodine has demonstrable anti-cancer effects and if it has, to find out the possible mechanism of its action. The MTT assay was performed to evaluate the cytotoxic effect. Depolarization of mitochondrial membrane potential, cell cycle, EGF receptor activity and apoptosis were recorded by FACS; profiles of different anti- and pro-apoptotic genes and their products were studied by semi-quantitative RT-PCR, indirect-ELISA, western blotting. Drug-DNA interaction was determined by CD spectroscopy. Administration of lycopodine down-regulated the expression of 5-lipoxygenase and the 5-oxo-ETE receptor (OXE receptor1) and EGF receptor, and caused up-regulation of cytochrome c with depolarization of mitochondrial inner membrane potential, without palpable change in p53 activity, resulting in apoptosis, cell arrest at G0/G1 stage and ultimately reduced proliferation of cancer cells; concomitantly, there was externalization of phosphotidyl serine residues. CD spectroscopic analysis revealed intercalating property of lycopodine with DNA molecule, implicating its ability to block cellular DNA synthesis. The overall results suggest that lycopodine is a promising candidate suitable for therapeutic use as an anti-cancer drug.


Asunto(s)
Alcaloides/farmacología , Apoptosis/efectos de los fármacos , Araquidonato 5-Lipooxigenasa/metabolismo , ADN/metabolismo , Potencial de la Membrana Mitocondrial/efectos de los fármacos , Neoplasias de la Próstata/patología , Quinolizinas/farmacología , Transducción de Señal/efectos de los fármacos , Alcaloides/metabolismo , Andrógenos/metabolismo , Animales , Antineoplásicos/metabolismo , Antineoplásicos/farmacología , Bovinos , Ciclo Celular/efectos de los fármacos , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , ADN/química , ADN/genética , Fragmentación del ADN/efectos de los fármacos , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Humanos , Masculino , Conformación de Ácido Nucleico/efectos de los fármacos , Quinolizinas/metabolismo , Proteína p53 Supresora de Tumor/metabolismo
15.
J Integr Med ; 11(2): 116-24, 2013 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-23506692

RESUMEN

OBJECTIVE: Preventive measures against skin melanoma like chemotherapy are useful but suffer from chronic side effects and drug resistance. Ethanolic extract of Phytolacca decandra (PD), used in homeopathy for the treatment of various ailments like chronic rheumatism, regular conjunctivitis, psoriasis, and in some skin diseases was tested for its possible anticancer potential. METHODS: Cytotoxicity of the drug was tested by conducting 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay on both normal (peripheral blood mononuclear cells) and A375 cells. Fluorescence microscopic study of 4',6-diamidino-2-phenylindole dihydrochloride-stained cells was conducted for DNA fragmentation assay, and changes in cellular morphology, if any, were also recorded. Lactate dehydrogenase activity assay was done to evaluate the percentages of apoptosis and necrosis. Reactive oxygen species (ROS) accumulation, if any, and expression study of apoptotic genes also were evaluated to pin-point the actual events of apoptosis. RESULTS: Results showed that PD administration caused a remarkable reduction in proliferation of A375 cells, without showing much cytotoxicity on peripheral blood mononuclear cells. Generation of ROS and DNA damage, which made the cancer cells prone to apoptosis, were found to be enhanced in PD-treated cells. These results were duly supported by the analytical data on expression of different cellular and nuclear proteins, as for example, by down-regulation of Akt and Bcl-2, up-regulation of p53, Bax and caspase 3, and an increase in number of cell deaths by apoptosis in A375 cells. CONCLUSION: Overall results demonstrate anticancer potentials of PD on A375 cells through activation of caspase-mediated signaling and ROS generation.


Asunto(s)
Antineoplásicos Fitogénicos/farmacología , Apoptosis/efectos de los fármacos , Medicamentos Herbarios Chinos/farmacología , Melanoma/metabolismo , Phytolacca/química , Especies Reactivas de Oxígeno/metabolismo , Neoplasias Cutáneas/metabolismo , Caspasa 3/genética , Caspasa 3/metabolismo , Línea Celular Tumoral , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Humanos , Melanoma/tratamiento farmacológico , Melanoma/genética , Melanoma/fisiopatología , Fitoterapia , Proteínas Proto-Oncogénicas c-bcl-2/genética , Proteínas Proto-Oncogénicas c-bcl-2/metabolismo , Transducción de Señal/efectos de los fármacos , Neoplasias Cutáneas/tratamiento farmacológico , Neoplasias Cutáneas/genética , Neoplasias Cutáneas/fisiopatología , Regulación hacia Arriba/efectos de los fármacos
16.
Exp Biol Med (Maywood) ; 237(1): 64-76, 2012 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-22169161

RESUMEN

Helonias dioica (HD) is a threatened species of herb growing in North America. It is used as a traditional medicine for treating various ailments particularly related to reproductive issues. The root is reported to contain approximately 10% of a saponin (chamaelirin; C(36)H(62)O(18)) apart from certain other fatty acids. As saponins are known to have hypoglycemic effects, we suspected its possible antihyperglycemic potentials. We injected intraperitoneally alloxan (ALX) at the dose of 200 mg/kg body weight (bw) to induce hyperglycemia in mice and tested possible hypoglycemic effects of HD in vivo by deploying two doses (100 and 200 mg/kg bw, respectively). We also tested its effects on the isolated pancreatic islets cells in vitro. We used various standard protocols like reactive oxygen species (ROS) generation and DNA damage, activities of biomarkers like catalase (CAT), superoxide dismutase (SOD), lipid peroxidase (LPO), reduced glutathione (GSH) of the pancreas tissue and glucokinase and glycogen content of the liver of hyperglycemic mice. With a mechanistic approach, we also tracked down the possible signaling pathway involved. We found an elevated level of ROS generation, LPO and overexpression of inducible nitric oxide synthase (iNOS), tumor necrosis factor α (TNF-α), p38 Map kinase (p38 MAPK), nuclear factor (NF)-κß, interferon gamma (IFN-γ), cytochrome c, caspase 3, poly [ADP ribose] polymerase (PARP) and cyclo oxygenase 2 (COX2) in ALX-induced diabetic mouse. Treatment of hyperglycemic mice with both the doses of HD showed a significant decrease with respect to all these parameters of study. Thus, our results suggest that HD prevents ALX-induced islet cell damage and possesses antihyperglycemic and antioxidative potentials.


Asunto(s)
Hiperglucemia/tratamiento farmacológico , Hipoglucemiantes/farmacología , Magnoliopsida , Estrés Oxidativo/efectos de los fármacos , Fitoterapia , Extractos Vegetales/farmacología , Plantas Medicinales/metabolismo , Aloxano , Animales , Caspasa 3/biosíntesis , Catalasa/metabolismo , Células Cultivadas , Ciclooxigenasa 2/biosíntesis , Citocromos c/biosíntesis , Daño del ADN , Especies en Peligro de Extinción , Glucoquinasa/metabolismo , Glutatión/metabolismo , Hiperglucemia/inducido químicamente , Hipoglucemiantes/administración & dosificación , Islotes Pancreáticos/efectos de los fármacos , Peróxidos Lipídicos/metabolismo , Glucógeno Hepático/análisis , Magnoliopsida/química , Ratones , FN-kappa B/biosíntesis , Óxido Nítrico Sintasa de Tipo II/biosíntesis , Páncreas/metabolismo , Extractos Vegetales/administración & dosificación , Raíces de Plantas/química , Poli(ADP-Ribosa) Polimerasas/biosíntesis , Especies Reactivas de Oxígeno/metabolismo , Saponinas/análisis , Saponinas/farmacología , Transducción de Señal , Superóxido Dismutasa/metabolismo , Factor de Necrosis Tumoral alfa/biosíntesis , Proteínas Quinasas p38 Activadas por Mitógenos/biosíntesis
17.
Chem Commun (Camb) ; 48(23): 2891-3, 2012 Mar 18.
Artículo en Inglés | MEDLINE | ID: mdl-22310528

RESUMEN

Mesoporous phosphosilicate nanoparticles of hollow sphere architecture have been prepared hydrothermally for the first time under acidic pH conditions and this material is found to be efficient in encapsulating an antibiotic drug and its controlled release at physiological pH for possible cargo delivery applications.


Asunto(s)
Antibacterianos/química , Portadores de Fármacos/química , Nanopartículas/química , Silicatos/química , Línea Celular Tumoral , Células HeLa , Humanos , Concentración de Iones de Hidrógeno , Nanopartículas/ultraestructura , Porosidad , Dióxido de Silicio/química
18.
Toxicol Lett ; 210(1): 34-43, 2012 Apr 05.
Artículo en Inglés | MEDLINE | ID: mdl-22285432

RESUMEN

Arsenic toxicity induces type 2 diabetes via stress mediated pathway. In this study, we attempt to reveal how sodium arsenite (iAs) could induce stress mediated impaired insulin signaling in mice and if an isolated active fraction of ginger, [6]-gingerol could attenuate the iAs intoxicated hyperglycemic condition of mice and bring about improvement in their impaired insulin signaling. [6]-Gingerol treatment reduced elevated blood glucose level and oxidative stress by enhancing activity of super oxide dismutase (SOD), catalase, glutathione peroxidase (GPx) and GSH. [6]-Gingerol also helped in increasing plasma insulin level, brought down after iAs exposure. iAs treatment to primary cell culture of ß-cells and hepatocytes in vitro produced cyto-degenerative effect and accumulated reactive oxygen species (ROS) in pancreatic ß-cells and hepatocytes of mice. [6]-Gingerol appeared to inhibit/intervene iAs induced cyto-degeneration of pancreatic ß-cells and hepatocytes, helped in scavenging the free radicals. The over-expression of TNFα and IL6 in iAs intoxicated mice was down-regulated by [6]-gingerol treatment. iAs intoxication reduced expression levels of GLUT4, IRS-1, IRS-2, PI3K, AKT, PPARγ signaling molecules; [6]-gingerol mediated its action through enhancing the expressions of these signaling molecules, both at protein and mRNA levels. Thus, our results suggest that [6]-gingerol possesses an anti-hyperglycemic property and can improve impaired insulin signaling in arsenic intoxicated mice.


Asunto(s)
Arsenitos/efectos adversos , Catecoles/farmacología , Alcoholes Grasos/farmacología , Insulina/agonistas , Estrés Oxidativo/efectos de los fármacos , Compuestos de Sodio/efectos adversos , Animales , Arsenitos/antagonistas & inhibidores , Glucemia/análisis , Catalasa/efectos de los fármacos , Catalasa/metabolismo , Glutatión Peroxidasa/efectos de los fármacos , Glutatión Peroxidasa/metabolismo , Hepatocitos/química , Hepatocitos/efectos de los fármacos , Insulina/sangre , Insulina/fisiología , Células Secretoras de Insulina/química , Células Secretoras de Insulina/efectos de los fármacos , Ratones , Especies Reactivas de Oxígeno/análisis , Transducción de Señal/efectos de los fármacos , Compuestos de Sodio/antagonistas & inhibidores , Superóxido Dismutasa/efectos de los fármacos , Superóxido Dismutasa/metabolismo
19.
Eur J Pharmacol ; 694(1-3): 20-9, 2012 Nov 05.
Artículo en Inglés | MEDLINE | ID: mdl-22939973

RESUMEN

[6]-Gingerol, a pharmacologically important bioactive component of ginger, has been reported to have anti-hyperglycemic, anti-cancer and anti-oxidative properties, but mechanisms through which these are achieved are largely unclear. The present study focuses on apoptosis and autophagy, two key events of anti-cancer activity, in HeLa cells treated with [6]-gingerol. The treated cells showed several morphological changes, including externalization of phosphatidyl serine, degradation of DNA and increase in TUNEL positivity. Furthermore, there was depolarization of mitochondrial membrane potential, providing evidence of mitochondria mediated apoptosis. The expression of caspase 3 and PARP was increased in cells exposed to [6]-gingerol. Circular dichroism study for testing drug-DNA interaction with both calf thymus and nuclear DNA as target revealed that the drug had potential to bind with the nuclear DNA and induce conformational changes of DNA. The over-expression of NFkß, AKT and Bcl2 genes in cancer cells was down-regulated by [6]-gingerol treatment. On the other hand the expression levels of TNFα, Bax and cytochrome c were enhanced in [6]-gingerol treated cells. Thus, overall results suggest that [6]-gingerol has potential to bind with DNA and induce cell death by autophagy and caspase 3 mediated apoptosis.


Asunto(s)
Antineoplásicos/farmacología , Apoptosis/efectos de los fármacos , Autofagia/efectos de los fármacos , Caspasa 3/metabolismo , Catecoles/farmacología , ADN/metabolismo , Alcoholes Grasos/farmacología , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Animales , Antineoplásicos/metabolismo , Antineoplásicos/farmacocinética , Antineoplásicos/toxicidad , Disponibilidad Biológica , Inhibidores de Caspasas/farmacología , Catecoles/metabolismo , Catecoles/farmacocinética , Catecoles/toxicidad , Bovinos , Núcleo Celular/efectos de los fármacos , Núcleo Celular/metabolismo , Supervivencia Celular/efectos de los fármacos , ADN/genética , Fragmentación del ADN/efectos de los fármacos , Alcoholes Grasos/metabolismo , Alcoholes Grasos/farmacocinética , Alcoholes Grasos/toxicidad , Células HeLa , Humanos , Ensayo de Materiales , Potencial de la Membrana Mitocondrial/efectos de los fármacos , Poli(ADP-Ribosa) Polimerasas/metabolismo , Proteolisis/efectos de los fármacos
20.
Eur J Pharm Sci ; 44(3): 207-17, 2011 Oct 09.
Artículo en Inglés | MEDLINE | ID: mdl-21839831

RESUMEN

We injected alloxan (100 mg/kg b.w.) in mice (Mus musculus) intra-peritoneally to induce hyperglycemia and divided the hyperglycemic mice into two sub-groups: one was fed ethanolic extract of Syzygium jambolanum (EESJ) (20 mg/kg b.w. for 8 weeks) and the other 85% ethyl alcohol ("vehicle"-control). Chromatographic and mass spectroscopic studies of EESJ revealed two principal components, one corresponding to an iridoid glycoside. We estimated blood glucose, glycosylated hemoglobin, glucokinase, and fructosamine and analyzed the expression of marker proteins like insulin, GLUT2, and GLUT4. We also studied anti-oxidant biomarkers like lipid peroxidase, superoxide dismutase, total thiole and catalase. We assayed generation of reactive oxygen species (ROS) and several inflammatory and apoptotic signal proteins like NFkB, IFNγ, iNOS, Bcl(2,) Bax, STAT1 and Caspase3. We further evaluated the effects of hyperglycemia on DNA through comet assay and DNA fragmentation study and assessed drug-DNA interaction by comparative analysis of circular dichroism (CD) spectral data and melting temperature profiles (T(m)) of calf thymus DNA treated with or without EESJ. We observed an elevation of all biomarkers for oxidative stress, generation of ROS and activation of NFkB and down regulation in expression of insulin, GLUT2 and glucokinase in hyperglycemic mice. Administration of EESJ reversed these changes. Histo-pathological observations of pancreas, liver and kidney also revealed relevant changes. Data of CD and (T(m)) indicated an interaction of EESJ with calf thymus DNA, indicating change in structure and conformation. Thus, EESJ has anti-oxidant as well as anti-hyperglycemic activities in diabetic mice, and potentially useful in management of hyperglycemia.


Asunto(s)
Glucemia/metabolismo , Daño del ADN , ADN/química , Diabetes Mellitus Experimental/tratamiento farmacológico , Hipoglucemiantes/uso terapéutico , Estrés Oxidativo/efectos de los fármacos , Extractos Vegetales/uso terapéutico , Transducción de Señal/efectos de los fármacos , Syzygium/química , Aloxano/farmacología , Animales , Antioxidantes/metabolismo , Biomarcadores/metabolismo , Compuestos de Bifenilo/química , Western Blotting , Supervivencia Celular/efectos de los fármacos , Dicroismo Circular , Ensayo Cometa , Diabetes Mellitus Experimental/sangre , Diabetes Mellitus Experimental/enzimología , Diabetes Mellitus Experimental/metabolismo , Etanol/química , Radicales Libres/química , Hipoglucemiantes/aislamiento & purificación , Hipoglucemiantes/farmacología , Riñón/efectos de los fármacos , Riñón/patología , Hígado/efectos de los fármacos , Hígado/patología , Espectroscopía de Resonancia Magnética , Espectrometría de Masas , Ratones , Páncreas/efectos de los fármacos , Páncreas/patología , Picratos/química , Extractos Vegetales/aislamiento & purificación , Extractos Vegetales/farmacología , Semillas/química , Espectroscopía Infrarroja por Transformada de Fourier
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