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1.
Oncogene ; 37(33): 4546-4561, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29743594

RESUMO

Although there is a strong correlation between multinucleated cells (MNCs) and cancer chemo-resistance in variety of cancers, our understanding of how multinucleated cells modulate the tumor micro-environment is limited. We captured multinucleated cells from triple-negative chemo-resistant breast cancers cells in a time frame, where they do not proliferate but rather significantly regulate their micro-environment. We show that oxidatively stressed MNCs induce chemo-resistance in vitro and in vivo by secreting VEGF and MIF. These factors act through the RAS/MAPK pathway to induce chemo-resistance by upregulating anti-apoptotic proteins. In MNCs, elevated reactive oxygen species (ROS) stabilizes HIF-1α contributing to increase production of VEGF and MIF. Together the data indicate, that the ROS-HIF-1α signaling axis is very crucial in regulation of chemo-resistance by MNCs. Targeting ROS-HIF-1α in future may help to abrogate drug resistance in breast cancer.


Assuntos
Resistencia a Medicamentos Antineoplásicos/fisiologia , Espécies Reativas de Oxigênio/metabolismo , Neoplasias de Mama Triplo Negativas/metabolismo , Mama/metabolismo , Linhagem Celular Tumoral , Feminino , Humanos , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Fatores Inibidores da Migração de Macrófagos/metabolismo , Transdução de Sinais/fisiologia , Microambiente Tumoral/fisiologia , Fator A de Crescimento do Endotélio Vascular/metabolismo
2.
Environ Toxicol Pharmacol ; 46: 131-139, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27458701

RESUMO

In this study, we examined potential adverse health effect of particulate matter (PM) collected from industrial areas of Rourkela, Odisha, India. Results indicate that PM in these areas contains benzo[a]pyrene in addition to other unidentified molecules. Ames test revealed the above PM to be highly mutagenic. Further studies of PM in HaCaT cells suggest its DNA damaging potential which may lead to apoptosis. Generation of reactive oxygen and nitrogen species following PM exposure may be an early event in the PM induced apoptosis. In addition, the activity of cytochrome P450 (CYP450), the key xenobiotic metabolism enzyme, was found to be increased following PM exposure indicating its role in PM induced toxicity. To confirm this, we used genetic and pharmacological inhibitors of CYP450 like CYP1B1 siRNA and Clotrimazole. Interestingly, we found that the use of these inhibitors significantly suppressed the PM induced apoptosis in HaCaT cells, which confirm the crucial role of CYP1B1 in the toxic manifestation of PM. For further analysis, blood samples were collected from the volunteer donor and analyzed for immunophenotypes and comet assay to survey any change in immune cells and DNA damage in blood cells respectively. The study was performed with 55 blood samples including 32 from industrial areas and 23 people from non-industrial zone of Rourkela city. Samples had a mean±SD age of 35±6.2years (35 men and 20 women). Our investigation did not observe any significant alteration in lymphocytes (P=0.671), B cell (P=0.104), cytotoxic T cell (P=0.512), helper T cell (P=0.396), NK cell (P=0.675) and monocytes (P=0.170) of blood cells from these two groups. Taken together; this study first time reports the possible health hazards of PM from industrial areas of Odisha, India.


Assuntos
Exposição Ambiental/análise , Material Particulado/análise , Material Particulado/toxicidade , Poluentes Atmosféricos/análise , Poluentes Atmosféricos/farmacocinética , Poluentes Atmosféricos/toxicidade , Animais , Apoptose/genética , Linhagem Celular , Cidades , Ensaio Cometa , Citocromo P-450 CYP1B1/genética , Citocromo P-450 CYP1B1/metabolismo , Dano ao DNA/efeitos dos fármacos , Humanos , Inativação Metabólica , Índia , Queratinócitos/efeitos dos fármacos , Queratinócitos/patologia , Espectroscopia de Ressonância Magnética , Camundongos , Testes de Mutagenicidade/métodos , Material Particulado/farmacocinética , Espécies Reativas de Oxigênio/metabolismo , Espectrometria de Fluorescência
3.
Biochem Res Int ; 2016: 3137010, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27293892

RESUMO

Melanoma is one of the most aggressive forms of cancer, usually resistant to standard chemotherapeutics. Despite a huge number of clinical trials, any success to find a chemotherapeutic agent that can effectively destroy melanoma is yet to be achieved. Para-phenylenediamine (p-PD) in the hair dyes is reported to purely serve as an external dyeing agent. Very little is known about whether p-PD has any effect on the melanin producing cells. We have demonstrated p-PD mediated apoptotic death of both human and mouse melanoma cells in vitro. Mouse melanoma tumour growth was also arrested by the apoptotic activity of intraperitoneal administration of p-PD with almost no side effects. This apoptosis is shown to occur primarily via loss of mitochondrial membrane potential (MMP), generation of reactive oxygen species (ROS), and caspase 8 activation. p-PD mediated apoptosis was also confirmed by the increase in sub-G0/G1 cell number. Thus, our experimental observation suggests that p-PD can be a potential less expensive candidate to be developed as a chemotherapeutic agent for melanoma.

4.
Future Microbiol ; 10(5): 763-89, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26000650

RESUMO

AIM: The effect of astrakurkurone, a novel triterpene, isolated from Indian mushroom Astraeus hygrometricus has been investigated to elucidate the mechanisms involved in selective cell death of Leishmania donovani. MATERIALS & METHODS: The hypotheses were investigated using flow-cytometry, scanning electron microscopy and confocal microscopy. RESULTS: The time dependent elevation of astrakurkurone-induced reactive oxygen species (ROS) was found intimately associated with apoptosis. The involvement of ROS in promastigote death was found confirmed as NAC and GSH could decrease the ROS level and restored the mitochondrial membrane potential (ΔΨ(m)). It also inhibited the intracellular amastigotes. CONCLUSION: We claim the present invention as substantial in depth evidences that mushroom derived active molecules can be exploited as target specific, comparatively nontoxic leads for antileishmanial therapy.


Assuntos
Antiprotozoários/farmacologia , Basidiomycota/química , Morte Celular/efeitos dos fármacos , Leishmania donovani/efeitos dos fármacos , Estresse Oxidativo , Espécies Reativas de Oxigênio/toxicidade , Triterpenos/farmacologia , Antiprotozoários/isolamento & purificação , Citometria de Fluxo , Leishmania donovani/fisiologia , Microscopia Confocal , Microscopia Eletrônica de Varredura , Fatores de Tempo , Triterpenos/isolamento & purificação
5.
J Pineal Res ; 58(3): 275-90, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25652673

RESUMO

Mitochondrial dysfunction due to oxidative damage is the key feature of several diseases. We have earlier reported mitochondrial damage resulting from the generation of oxidative stress as a major pathophysiological effect of isoproterenol (ISO)-induced myocardial ischemia in rats. That melatonin is an antioxidant that ameliorates oxidative stress in experimental animals as well as in humans is well established. We previously demonstrated that melatonin provides cardioprotection against ISO-induced myocardial injury as a result of its antioxidant properties. The mechanism of ISO-induced cardiac mitochondrial damage and protection by melatonin, however, remains to be elucidated in vitro. In this study, we provide evidence that ISO causes dysfunction of isolated goat heart mitochondria. Incubation of cardiac mitochondria with increasing concentrations of ISO decreased mitochondrial succinate dehydrogenase (SDH) activity, which plays a pivotal role in mitochondrial bioenergetics, as well as altered the activities of other key enzymes of the Kreb's cycle and the respiratory chain. Co-incubation of ISO-challenged mitochondria with melatonin prevented the alterations in enzyme activity. That these changes in mitochondrial energy metabolism were due to the perpetration of oxidative stress by ISO was evident from the increased levels of lipid peroxidation and decreased reduced glutathione/oxidized glutathione ratio. ISO-induced oxidative stress also altered mitochondrial redox potential and brought about changes in the activity of the antioxidant enzymes manganese superoxide dismutase and glutathione peroxidase, eventually leading to alterations in total ATPase activity and membrane potential. Melatonin ameliorated these changes likely through its antioxidant abilities suggesting a possible mechanism of cardioprotection by this indole against ISO-induced myocardial injury.


Assuntos
Antioxidantes/farmacologia , Isoproterenol/efeitos adversos , Melatonina/farmacologia , Mitocôndrias Cardíacas/efeitos dos fármacos , Mitocôndrias Cardíacas/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Animais , Cabras , Peroxidação de Lipídeos/efeitos dos fármacos , Mitocôndrias Cardíacas/enzimologia , Mitocôndrias Cardíacas/patologia
6.
Colloids Surf B Biointerfaces ; 126: 426-36, 2015 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-25579219

RESUMO

The objective of the present study was to fabricate and monitor real-time, impact of a stable conjugated linolenic acid, α-eleostearic acid (ESA) rich nanoemulsion (NE) formulation (d < 200 nm) vis-à-vis ESA conventional emulsion (CE) system in ex vivo systems against both endogenous and exogenous reactive oxygen species (ROS). Accordingly, stable nanoemulsion formulation of ESA was engineered with the aid of bitter melon seed oil and non-toxic excipients. Morphology and particle size of the emulsion formulations were studied to validate stability. The real-time rapid uptake of the ESA NE and its increased prophylactic efficacy against induced endogenous and exogenous ROS in terms of cell viability and membrane integrity was evaluated flow-cytometrically and with fluorescence microscopic analysis of different primary cells. It was found that the fabricated non-toxic ESA NE had stable parameters (hydrodynamic mean diameter, particle size distribution and zeta potential) for over 12 weeks. Further, ESA NE at a concentration of ∼ 70 µM exhibited maximum efficacy in protecting cells from oxidative damage against both endogenous and exogenous ROS in lymphocytes and hepatocytes as compared to its corresponding presence in the CE formulation. This study provides a real-time empirical evidence on the influence of nano formulation in enhancing bioavailability and antioxidative properties of ESA.


Assuntos
Leucócitos Mononucleares/química , Nanoestruturas/química , Ácido alfa-Linolênico/química , Morte Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Emulsões/química , Emulsões/farmacologia , Humanos , Leucócitos Mononucleares/citologia , Leucócitos Mononucleares/metabolismo , Substâncias Macromoleculares/química , Substâncias Macromoleculares/farmacologia , Tamanho da Partícula , Espécies Reativas de Oxigênio/metabolismo , Relação Estrutura-Atividade , Propriedades de Superfície , Fatores de Tempo , Ácido alfa-Linolênico/farmacologia
7.
Protoplasma ; 252(1): 283-99, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25052711

RESUMO

The genus Drimia (syn. Urginea), commonly called squill, represents a species complex, infrageneric delimitation being ill-defined due to morphological variability, population variation within species and polyploidy. In the present study, fluorescent chromosome banding and measurements of nuclear DNA content by flow cytometry were performed in five Indian species of Drimia: Drimia indica, Drimia polyantha, Drimia razii, Drimia wightii and Drimia coromandeliana to elucidate taxonomic relationship and obtain possible insights into the evolutionary processes within this group. All taxa analyzed exhibited similar karyomorphology with subtle differences accounted by nucleolar chromosomes. Nuclear DNA content ranged from 20.41 pg/2C in D. polyantha to 40.80 pg/2C in D. coromandeliana and was positively correlated with chromosome number (r = 0.67, P = 0.02) and total diploid chromatin length (r = 0.59, P = 0.06). Fluorescent chromosome banding revealed the presence of CMA(+ve)/DAPI(-ve) signals associated with nucleolar chromosomes presumably coincident with NOR in all species and unique CMA(+ve) signals in diploid populations of D. indica. Satellite polymorphism between homologous NOR-bearing chromosomes was observed which supports hybrid origin of the taxon. UPGMA dendrogram and scatter diagrams based on karyological parameters indicated a close relationship of D. indica, D. razii and D. polyantha while D. wightii and D. coromandeliana appeared distant. D. wightii appeared more close to D. indica than to all other species based on genome size and karyomorphology. As a whole, D. indica showed high intra-specific variability with populations exhibiting intergrading characters with other species. In conclusion, it is likely that hybridization followed by reproductive isolation of polymorphic forms arising by adaptation to different ecological niches resulted in species diversification of Drimia in India, probably from a common ancestor similar to D. indica.


Assuntos
Bandeamento Cromossômico/métodos , DNA de Plantas/genética , Hibridização Genética/genética , Liliaceae/química , Índia , Cariotipagem , Liliaceae/crescimento & desenvolvimento
8.
Clin Hemorheol Microcirc ; 59(1): 67-81, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-24531124

RESUMO

Platelet signatures indicating differential dysfunction, hyperactivation, aggregation or adhesion are capable of expressing their characters during the journey of a disease process, and can be utilized as cost effective biomarkers with immense clinical value. Type 2 diabetes mellitus (T2DM) is a major lifestyle disease of contemporary world with progression to diabetes associated cardiovascular diseases (DM-CVD). We identified a few potential biomarkers in platelets of T2DM to analyze the thrombotic risk in diabetes subjects by utilizing flow cytometric quantification with different flurochrome conjugated monoclonal antibodies. Our study describes interesting correlations (p<0.0001) for different clinical parameters of concurrent threat for vessel occlusion and the status of indices like reactive oxygen species, von Willebrand factor and mitochondrial membrane potential using western blotting and fluorescence techniques. Our study involved 32 T2DM, and 31 T2DM-CVD subjects compared to 29 healthy controls without any history of T2DM or CVD. An altered expression of platelet surface markers P-selectin (CD62p) and GpIIb/IIIa (CD 41/61, PAC1) along with changes in the platelet size due to agonist induced activation contributed to the enhanced thrombotic potential in the patients. This work elucidates the prospect of platelet biomarkers as diagnostic tool to predict cardiovascular risk in DM subjects.


Assuntos
Plaquetas/patologia , Doenças Cardiovasculares/complicações , Doenças Cardiovasculares/diagnóstico , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/diagnóstico , Biomarcadores/análise , Feminino , Citometria de Fluxo , Humanos , Masculino , Potencial da Membrana Mitocondrial , Pessoa de Meia-Idade , Selectina-P/análise , Complexo Glicoproteico GPIIb-IIIa de Plaquetas/análise , Espécies Reativas de Oxigênio/análise , Fatores de Risco , Fator de von Willebrand/análise
9.
Clin Hemorheol Microcirc ; 59(4): 287-300, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-23603328

RESUMO

Studies of RBC morphological alterations, despite their potential clinical and experimental application, are compromised due to lack of simple and rapid techniques. As a complementary approach toward quantitative microscopy, we have reconstituted morphological information from light scattering data obtained from flow cytometer. Normal and poikilocytic agent treated samples were analyzed by microscopy and respective morphological index (MI) was calculated from the morphology based scores assigned to RBC. The samples were simultaneously analyzed by flowcytometer and the scatter data were obtained. Accordingly, the best correlated parameters of both forward scatter and side scatter were chosen to formulate a suitable regression model with MI as response. Flow cytometry data was also verified with another instrument (BD FACS Verse) and the equation obtained was validated with separate set of samples. The multivariate regression analysis yields a quadratic model with MI as response (R2 = 0.96, p <  0.001). The flow cytometric data from both instruments were in good agreement (Intra class correlation ∼0.9, p <  0.001). The model was found to simulate the sample MI with high accuracy (R2 = 0.97, p <  0.001). This proposed method was verified to be simple, rapid, quantitative and cost effective for the measurement of morphological alteration of RBC.


Assuntos
Eritrócitos/patologia , Citometria de Fluxo , Adulto , Feminino , Humanos , Luz , Masculino , Espalhamento de Radiação
10.
Cytometry A ; 85(10): 833-40, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24853918

RESUMO

The family Hyacinthaceae constitutes about 900 species of bulbous geophytes usually characterized by high mucilage content. Taxonomic delimitation of Hyacinthaceae has been controversial since the time of Linnaeus due to the absence of reliable discriminating characters. Pattern of genome size variation can thus be considered as an added character to aid intergeneric and intrageneric relationship of the group. However, reports on genome size estimation by flow cytometric analysis of these plants are rare due to the presence of mucilage, which causes problem with nuclei sample preparation. To overcome this problem five reported nuclei isolation buffers were tested in Drimia indica of which Galbraith's buffer gave comparatively better results and was further modified by increasing pH, detergent concentration, and replacing sodium citrate by citric acid. The modified buffer enabled better sample preparation with increased yield, lesser debris, and improved DNA peak CV. The standardized buffer was used to estimate the 2C values of Drimia indica, Drimia nagarjunae, Drimia wightii, Drimia coromandeliana, and Ledebouria revoluta for the first time by flow cytometric analysis. This study also opens up the scope for further improvement in sample preparation for flow cytometric analysis of mucilaginous plants, which is otherwise problematic due to nuclei clumping and increased viscosity of sample.


Assuntos
DNA de Plantas/genética , Citometria de Fluxo/métodos , Tamanho do Genoma/genética , Liliaceae/genética , Mucilagem Vegetal/genética , Mucilagem Vegetal/análise , Raízes de Plantas/genética , Especificidade da Espécie
11.
Food Chem Toxicol ; 66: 262-77, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24508525

RESUMO

Arsenic is a well known global groundwater contaminant. Exposure of human body to arsenic causes various hazardous effects via oxidative stress. Nutrition is an important susceptible factor which can affect arsenic toxicity by several plausible mechanisms. Development of modern civilization led to alteration in the lifestyle as well as food habits of the people both in urban and rural areas which led to increased use of junk food containing high level of fat. The present study was aimed at investigating the effect of high fat diet on heart and liver tissues of rats when they were co-treated with arsenic. This study was established by elucidating heart weight to body weight ratio as well as analysis of the various functional markers, oxidative stress biomarkers and also the activity of the antioxidant enzymes. Histological analysis confirmed the biochemical investigations. From this study it can be concluded that high fat diet increased arsenic induced oxidative stress.


Assuntos
Arsênio/toxicidade , Dieta Hiperlipídica , Coração/efeitos dos fármacos , Fígado/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Animais , Peso Corporal/efeitos dos fármacos , Relação Dose-Resposta a Droga , Testes de Função Cardíaca , Testes de Função Hepática , Masculino , Tamanho do Órgão/efeitos dos fármacos , Ratos , Ratos Wistar
12.
PLoS One ; 8(1): e53504, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23326443

RESUMO

A unique event in bacterial epidemiology was the emergence of the El Tor biotype of Vibrio cholerae O1 and the subsequent rapid displacement of the existing classical biotype as the predominant cause of epidemic cholera. We demonstrate that when the El Tor and classical biotypes were cocultured in standard laboratory medium a precipitous decline in colony forming units (CFU) of the classical biotype occurred in a contact dependent manner. Several lines of evidence including DNA release, microscopy and flow cytometric analysis indicated that the drastic reduction in CFU of the classical biotype in cocultures was not accompanied by lysis, although when the classical biotype was grown individually in monocultures, lysis of the cells occurred concomitant with decrease in CFU starting from late stationary phase. Furthermore, uptake of a membrane potential sensitive dye and protection of genomic DNA from extracellular DNase strongly suggested that the classical biotype cells in cocultures retained viability in spite of loss of culturability. These results suggest that coculturing the classical biotype with the El Tor biotype protects the former from lysis allowing the cells to remain viable in spite of the loss of culturability. The stationary phase sigma factor RpoS may have a role in the loss of culturability of the classical biotype in cocultures. Although competitive exclusion of closely related strains has been reported for several bacterial species, conversion of the target bacterial population to the viable non-culturable state has not been demonstrated previously and may have important implications in the evolution of bacterial strains.


Assuntos
Técnicas de Tipagem Bacteriana/métodos , Viabilidade Microbiana , Vibrio cholerae/classificação , Vibrio cholerae/crescimento & desenvolvimento , Bacteriólise , Técnicas de Cocultura , Contagem de Colônia Microbiana , Desoxirribonucleases/metabolismo , Citometria de Fluxo , Concentração de Íons de Hidrogênio , Ensaios de Proteção de Nucleases , Vibrio cholerae/citologia
13.
Mutat Res ; 749(1-2): 60-9, 2012 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-22960309

RESUMO

The biocidal effect of silver nanoparticles (Ag-np) has resulted in their incorporation into consumer products. While the population exposed to Ag-np continues to increase with ever new applications, Ag-np remains a controversial research area with regard to their toxicity in biological systems. Here a genotoxic and cytotoxic approach was employed to elucidate the activity of Ag-np in vitro and in vivo. Characterization of Ag-np using scanning electron microscopy revealed a size range of 90-180nm. Cytotoxic potential of Ag-np was evaluated in human lymphocytes via cell viability assay (Trypan blue dye exclusion method, MTT and WST assay). The uptake and incorporation of Ag-np into the lymphocytes was confirmed by flow cytometry. Additionally apoptosis (AnnexinV-FITC-PI staining) and DNA strand breaks (comet assay) in human lymphocytes revealed that Ag-np at concentration 25µg/ml can cause genotoxicity. In vivo experiments on plants (Allium cepa and Nicotiana tabacum) and animal (Swiss albino male mice) showed impairment of nuclear DNA. Induction of oxidative stress was also studied. The DNA damage and chromosomal aberrations raise the concern about the safety associated with applications of the Ag-np. A single ip administration of Ag-np gave a significant (P≤0.05) increase in the frequency of aberrant cells and Tail DNA percent at concentrations 10mg/kg body weight and above. Results of comet assay in A. cepa and N. tabacum demonstrated that the genotoxic effect of Ag-np was more pronounced in root than shoot/leaf of the plants. The present study indicated a good correlation between the in vitro and in vivo experiments. Therefore the biological applications employing Ag-np should be given special attention besides adapting the antimicrobial potential.


Assuntos
Dano ao DNA , Mutagênicos/toxicidade , Nanopartículas/toxicidade , Prata/toxicidade , Animais , Apoptose , Células da Medula Óssea , Ensaio Cometa , Humanos , Linfócitos/efeitos dos fármacos , Camundongos , Cebolas , Espécies Reativas de Oxigênio , Nicotiana
14.
Int J Med Mushrooms ; 13(5): 427-40, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-22324408

RESUMO

Previously, we reported the in vitro anticancer and immunomodulatory effect of a protein fraction designated as Cibacron blue affinity purified protein (CBAEP) obtained from the culinary-medicinal oyster mushroom, Pleurotus ostreatus. In the present study, we investigated the in vivo antitumor potential of CBAEP in different tumor-bearing mice models and studied the detailed mechanism of tumor regression in Dalton lymphoma (DL)-bearing mice. The lethal dose (LD50) of CBAEP was found to be 55 mg/kg body weight and sublethal doses (5 mg/kg and 10 mg/kg body weight) showed a prolonged tumor survival time in DL, Sarcoma-180, and B16F0 melanoma tumor-bearing mice. Further, CBAEP reduced about 35.68 and 51.43% DL cell growth in 5 and 10 mg/kg body weight, respectively. The in vivo CBAEP treatment showed an apoptotic feature as demonstrated in morphological study and sub-G0/G1 population in cell cycle and Western blot of DL cells. CBAEP also activated immunosuppression condition in DL tumor-bearing host. It also stimulated immune cells in the presence of nonspecific immunostunulator (LPS and ConA) ex vivo as well as enhanced Th1 response with production of TNF-α, IFN-γ, and IL-2. Moreover, it activated tumor-associated macrophages and NK cells. The present findings revealed the potent antitumor property of CBAEP, which might help in developing a new anticancer drug.


Assuntos
Antineoplásicos/farmacologia , Proteínas Fúngicas/uso terapêutico , Linfoma/tratamento farmacológico , Pleurotus/química , Sarcoma 180/tratamento farmacológico , Animais , Antineoplásicos/química , Camundongos , Camundongos Endogâmicos C57BL
15.
Cell Biol Int ; 35(6): 617-21, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21143204

RESUMO

Mushroom-derived polysaccharides like ß-glucan are being investigated for therapeutic properties for a long time, but their mode of action of immunomodulatory properties is not well established. In the present study, a heteroglucan from Astraeus hygrometricus designated as AE2 is investigated for its macrophage stimulatory properties using RAW 264.7 cell line. An augmentation of nitric oxide production is observed in the presence of AE2 in a dose-dependent manner due to up-regulation of iNOS (inducible NO synthase) expression; hence NF κB (nuclear factor κB) pathway is investigated. RAW 264.7 cells endured phosphorylation of Ikk (IκB kinase) and subsequently NF κB is translocated to the nucleus. Further, the PKC (protein kinase C) level of the cells enhanced significantly. We also found that AE2 could induce the phosphorylation of p38 MAPK (mitogen-activated protein kinase), ERK1/2 (extracellular-signal-regulated kinase 1/2), MEK (MAPK/ERK kinase) and JNK (c-Jun N-terminal kinase), whereas it failed to induce phosphorylation of JAK2 (Janus kinase 2) and STAT1. These results indicated that the macrophage activation by AE2 might be exerted, at least in part, via MAPKs (mitogen-activated protein kinases) pathway of signal transduction.


Assuntos
Basidiomycota/metabolismo , Glucanos/farmacologia , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Animais , Linhagem Celular Tumoral , Proteínas I-kappa B/genética , Proteínas I-kappa B/metabolismo , Proteínas Quinases JNK Ativadas por Mitógeno/genética , Proteínas Quinases JNK Ativadas por Mitógeno/metabolismo , Janus Quinase 2/genética , Janus Quinase 2/metabolismo , Camundongos , Proteína Quinase 1 Ativada por Mitógeno/genética , Proteína Quinase 1 Ativada por Mitógeno/metabolismo , Proteína Quinase 3 Ativada por Mitógeno/genética , Proteína Quinase 3 Ativada por Mitógeno/metabolismo , NF-kappa B/genética , NF-kappa B/metabolismo , Óxido Nítrico/metabolismo , Óxido Nítrico Sintase Tipo II/genética , Óxido Nítrico Sintase Tipo II/metabolismo , Fosforilação , Fator de Transcrição STAT1/genética , Fator de Transcrição STAT1/metabolismo , Proteínas Quinases p38 Ativadas por Mitógeno/genética , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo
16.
J Med Food ; 13(3): 665-72, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20521989

RESUMO

Mushrooms have been used as food and for therapeutic purpose for decades, and various compounds derived from these have potential biological activities. Application of such agents of natural origin is vital with relevance to an increase in diseases involving immune dysfunction, cancer, and autoimmune conditions in recent years. These compounds belong mainly to polysaccharides, especially beta-D-glucan, glycopeptide/protein complexes, proteoglycans, proteins, and triterpenoids. Among these compounds, polysaccharides and their peptide/protein derivates have extremely important roles in immunomodulating activities. The present study aims to explore the immunomodulatory properties of polysaccharide isolated from the mushroom Astraeus hygrometricus. The polysaccharide isolated by hot alkaline extraction and chromatography was designated as AE2 and studied for its immunostimulatory potential in vivo in a murine model. Macrophages from treated mice showed higher production of nitric oxide and interleukin-1 and also exhibited an increased phagocytic potential. It also enhanced natural killer cell activation and proliferation of splenocytes with an increase in the T-helper (Th) 1 cytokine level of splenocyte culture supernatant. The cytokine level in serum also indicated a Th1 skew. The observed activities were associated with no general toxicity to the organism. The findings will be helpful in considering A. hygrometricus as a potential source of an immunomodulator and in designing further studies to understand its mode of action on immune system.


Assuntos
Basidiomycota/imunologia , Fatores Imunológicos/imunologia , Polissacarídeos/imunologia , Animais , Basidiomycota/química , Células Cultivadas , Citocinas/imunologia , Fatores Imunológicos/isolamento & purificação , Fatores Imunológicos/farmacologia , Células Matadoras Naturais/efeitos dos fármacos , Células Matadoras Naturais/imunologia , Ativação Linfocitária/efeitos dos fármacos , Macrófagos/efeitos dos fármacos , Macrófagos/imunologia , Masculino , Camundongos , Polissacarídeos/isolamento & purificação , Polissacarídeos/farmacologia
17.
Cell Biol Int ; 34(5): 553-63, 2010 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-20384587

RESUMO

Most tumours arise from a single normal cell through a sequential evolutionary process of mutation and selection. Tumours are initiated by escaping non-immune surveillance, which includes defective DNA repair, epigenetic gene alternation, resistance to apoptosis and loss of intercellular contact inhibition. Tumour cells harbour mutations in a number of critical genes that provide selective advantages at various stages during the evolution of the tumour. The tumour cells that circumvent the tumour suppressor mechanisms of the non-immune surveillance process are edited by the immune system, resulting in the selection of a resistant tumour variant. The selection of the tumour cell is further shaped by its interactions with cells and other factors in its microenvironment. Tumour evolution is thought to adhere to Darwinian principles by escaping both non-immune (intrinsic) and immune (extrinsic) responses against self-altered tumour cells. At end-stage, tumours have escaped both non-immune and immune surveillance with increased threshold of apoptosis. Combination therapy has been proposed, by exploring the non-immune and immune suppressive nature of the tumour, and has been found to have a therapeutic efficiency on tumour regression as compared with monotherapies. The combination of immunotherapy and other different modalities, especially vaccines, with conventional anticancer therapies with optimized dosage and scheduling can offer synergistic antitumour effects. Here, we focus on the mechanism of tumour evolution and its implication in combination therapy.


Assuntos
Imunoterapia/métodos , Neoplasias/imunologia , Neoplasias/terapia , Evasão Tumoral/imunologia , Apoptose/imunologia , Vacinas Anticâncer/uso terapêutico , Terapia Combinada , Epigênese Genética , Humanos , Sistema Imunitário/imunologia , Vigilância Imunológica/imunologia , Linfócitos/imunologia , Neoplasias/genética , Neoplasias/patologia
18.
Cell Biol Int ; 33(7): 720-7, 2009 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-19422926

RESUMO

In our previous study, Abrus abrin derived peptide fraction (ABP) with molecular weight in range of 600-1500Da was shown to have potent antitumor activity in Dalton's lymphoma (DL) tumor bearing mice. The purpose of this study was to elucidate the mechanism of mitochondrial apoptosis induced by the peptide fraction. ABP was found to have selective antiproliferative activity (10ng-100ng/ml) on several tumor cell lines in vitro without having any cytotoxic effect on normal cell lines with a dose of 1000ng/ml. Analysis of the growth inhibitory mechanism in HeLa cells revealed DNA fragmentation with appearance of the sub G(0)/G(1) peak indicative of apoptosis. Further investigation results showed that the apoptotic machinery of HeLa induced by ABP was associated with the release of reactive oxygen species, a drop in mitochondrial transmembrane potential, upregulation of Bax, downregulation of Bcl-2, and activation of caspase-3. The peptide fraction was found to target mitochondria of HeLa cells as observed by confocal microscopy. This peptide fraction offers a source of mitochondria penetrating peptides which might have therapeutic induction of apoptosis in cancer cells.


Assuntos
Abrina/química , Abrus/química , Antineoplásicos Fitogênicos/farmacologia , Apoptose , Mitocôndrias/metabolismo , Peptídeos/farmacologia , Caspase 3/metabolismo , Linhagem Celular Tumoral , Células HeLa , Humanos , Interfase , Potenciais da Membrana , Mitocôndrias/efeitos dos fármacos , Peptídeos/química , Proteína X Associada a bcl-2/metabolismo
19.
Phytomedicine ; 16(8): 776-82, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19303750

RESUMO

In vitro immunostimulatory effect of Abrus lectins derived peptide fractions (AGP and ABP) was investigated in DL bearing mice. Both AGP and ABP were found to activate splenocytes and induced production of cytokines like IL-2, IFN-gamma and TNF-alpha indicating a Th1 type of immune response. Analysis of in vitro treated splenocytes by flow cytometry revealed an increase in percentage of T and B cell with high expression of activation markers (CD25(+) and CD71(+)). At the same time, expression of co-stimulatory markers was significantly high compared to tumor control. The tumor associated macrophages were able to stimulate NO production, IL-1 secretion, increased phagocytosis and decreased expression of mannose receptor. It was also observed that NK cell was activated by AGP and ABP. These results suggest that both AGP and ABP act as immunostimulants in vitro in DL bearing mice.


Assuntos
Abrina/metabolismo , Abrus/química , Adjuvantes Imunológicos/uso terapêutico , Aglutininas/metabolismo , Antineoplásicos Fitogênicos/uso terapêutico , Linfoma/tratamento farmacológico , Peptídeos/uso terapêutico , Adjuvantes Imunológicos/farmacologia , Animais , Antígenos CD/metabolismo , Antineoplásicos Fitogênicos/farmacologia , Linfócitos B/efeitos dos fármacos , Linhagem Celular Tumoral , Citocinas/biossíntese , Citocinas/metabolismo , Subunidade alfa de Receptor de Interleucina-2/metabolismo , Células Matadoras Naturais/efeitos dos fármacos , Lectinas Tipo C/antagonistas & inibidores , Macrófagos/efeitos dos fármacos , Receptor de Manose , Lectinas de Ligação a Manose/antagonistas & inibidores , Camundongos , Óxido Nítrico/biossíntese , Peptídeos/metabolismo , Peptídeos/farmacologia , Fagocitose/efeitos dos fármacos , Fitoterapia , Extratos Vegetais/farmacologia , Extratos Vegetais/uso terapêutico , Plantas Medicinais/química , Receptores de Superfície Celular/antagonistas & inibidores , Receptores da Transferrina/metabolismo , Sementes , Baço/citologia , Baço/efeitos dos fármacos , Linfócitos T/efeitos dos fármacos
20.
Immunobiology ; 214(3): 227-34, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19215805

RESUMO

In our previous studies, Abrus agglutinin showed non-specific immunostimulatory activity both native (NA) and heat-denatured (HDA) condition in mouse model. The present study was investigated to decipher the specific immune response towards B and T cell by NA and HDA. It was observed that the proliferation index for NA and HDA of stimulated B cells are 1.35 and 1.41 respectively and on the other hand, T cell proliferation index for NA and HDA are 1.67 and 1.54 respectively. At the same time, expression of surface and activation marker for B and T cells was significantly different compared to control as quantified by flow cytometry. But the expression of co-stimulatory markers (CD 80 and CD 86) was not significantly different and NA and HDA in immunized splenocytes with Dalton's lymphoma antigen induced antibodies titer 4.37 and 4.2 times more than control. This study indicates Abrus agglutinin (NA and HDA) acts as a B cell and T cell stimulator.


Assuntos
Abrus/imunologia , Linfócitos B/metabolismo , Ativação Linfocitária/efeitos dos fármacos , Lectinas de Plantas/farmacologia , Linfócitos T/metabolismo , Animais , Linfócitos B/citologia , Linfócitos B/efeitos dos fármacos , Linfócitos B/imunologia , Antígeno B7-1/genética , Antígeno B7-1/imunologia , Antígeno B7-1/metabolismo , Proliferação de Células/efeitos dos fármacos , Ciclosporina/farmacologia , Citometria de Fluxo , Temperatura Alta , Separação Imunomagnética , Ativação Linfocitária/imunologia , Camundongos , Lectinas de Plantas/química , Conformação Proteica , Desnaturação Proteica , Sementes , Baço/citologia , Linfócitos T/citologia , Linfócitos T/efeitos dos fármacos , Linfócitos T/imunologia
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