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1.
Nutrients ; 13(3)2021 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-33670884

RESUMO

Although mandatory fortification of oil with vitamin A is efficacious, its effectiveness can be compromised by suboptimal compliance to standards. In this study, we assessed (1) the availability of oil brands across the eight divisions of Bangladesh, (2) fortification quality (the extent to which vitamin A content is aligned with fortification standards) of oil brands and producers and (3) the market volume represented by available edible oil types. We visited different retail outlets in rural and urban market hubs to ascertain available oil brands and bulk oil types and collected samples. We used high-performance liquid chromatography to quantify average vitamin A content and compared them to the national oil fortification standards. Among the 66 packaged brands analyzed, 26 (39%) were not fortified, and 40 (61%) were fortified, with 28 (42%) fortified above the standard vitamin A minimum. Among the 41 bulk oil type composites analyzed, 24 (59%) were not fortified, and 17 (41%) were fortified, with 14 (34%) fortified below and 3 (7%) fortified above the standard minimum. Vitamin A fortification is high for packaged and branded edible oil but low for oil sold in unbranded, loose form. As bulk oil makes up a large proportion of the oil market volume, this means the majority of the oil volume available to the population is either not (25%) or fortified below the standard requirement (39%). Regulatory inspections of producers selling bulk oil should be prioritized to support and incentivize the industry to make all oil traceable and fortified to standard.


Assuntos
Gorduras Insaturadas na Dieta/análise , Alimentos Fortificados/análise , Vitamina A/análise , Bangladesh , Gorduras Insaturadas na Dieta/classificação , Rotulagem de Alimentos , Qualidade dos Alimentos , Alimentos Fortificados/normas , Humanos , Supermercados , Vitamina A/administração & dosagem
2.
J Diet Suppl ; 9(1): 1-8, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22432798

RESUMO

Parkinson's disease (PD) is characterized by the progressive loss of dopaminergic neurons and the aggression of alpha Synuclein (αS) in the brain. Drosophila mutants and transgenes have provided a platform to understand the mechanistic insight associated with the degenerative diseases. A number of polyphenols have been reported to inhibit the αS aggregation resulting in the possible prevention of PD. The involvement of free radicals in mediating the neuronal death in PD has also been implicated. In the present study, the effect of Nordihydroguaiaretic acid (NDGA) was studied on the climbing ability of the PD model Drosophila expressing normal human alpha synuclein (h-αS) in the neurons. These flies exhibit locomotor dysfunction as the age progresses. NDGA at final concentration of 0.01, 0.1, 0.5, and 1µl/ml was supplemented with the diet and the flies were allowed to feed for the 24 days. NDGA at 0.01 µl/ml did not showed any significant delay in the loss of climbing ability of PD model flies. However, NDGA doses at 0.1, 0.5, and 1.0 µl/ml showed a dose dependent significant (p < .05) delay in the loss of climbing ability of PD model flies as compared to the untreated PD flies. The results suggest that the NDGA is potent in delaying the climbing disability of PD model flies and also supports the utility of this model in studying PD symptoms.


Assuntos
Suplementos Nutricionais , Locomoção/efeitos dos fármacos , Masoprocol/uso terapêutico , Doença de Parkinson/prevenção & controle , Fitoterapia , Extratos Vegetais/uso terapêutico , alfa-Sinucleína/antagonistas & inibidores , Animais , Animais Geneticamente Modificados , Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Modelos Animais de Doenças , Neurônios Dopaminérgicos/metabolismo , Relação Dose-Resposta a Droga , Proteínas de Drosophila/antagonistas & inibidores , Drosophila melanogaster , Radicais Livres/metabolismo , Humanos , Masoprocol/farmacologia , Mutação , Doença de Parkinson/metabolismo , Extratos Vegetais/farmacologia
3.
Drug Chem Toxicol ; 35(2): 119-26, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21995272

RESUMO

In India, natural preparations derived from the plants are widely use for the treatments of various diseases. Hence, it becomes necessary to assess the modulating action of the plant extract when associated with other substances. Potassium canrenoate (PC) is a synthetic steroid and is used in the treatment of hypertension. It is not only a genotoxic agent, but also a tumor-initiating agent. In the present study, the effect of various doses (i.e., 5, 10, 20, and 30 µM) of PC were studied for their genotoxic effects in the presence of S9 mix in cultured human lymphocytes, using mitotic index, chromosomal aberrations, sister chromatid exchanges, and replication index as parameters. PC was found to be genotoxic at 20 and 30 µM. Treatment of 30 µM of PC was given along with different doses of Plumbago zeylanica extract (i.e., 107.5, 212.5, 315, and 417 µg/mL) of the culture medium. A dose-dependent decrease in the genotoxic effects of PC was observed. The result suggested that the plant extract per se does not have genotoxic potential, but can modulate the genotoxicity of PC in cultured human lymphocytes.


Assuntos
Ácido Canrenoico/toxicidade , Leucócitos Mononucleares/efeitos dos fármacos , Mutagênicos/toxicidade , Extratos Vegetais/farmacologia , Plumbaginaceae/química , Ácido Canrenoico/antagonistas & inibidores , Ciclo Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Aberrações Cromossômicas/induzido quimicamente , Aberrações Cromossômicas/efeitos dos fármacos , Interações Medicamentosas , Humanos , Índia , Extratos Vegetais/isolamento & purificação , Troca de Cromátide Irmã/efeitos dos fármacos
4.
Interdiscip Toxicol ; 4(3): 159-65, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22058658

RESUMO

Methyl methanesulfonate (MMS) is an anti-carcinogenic drug and its toxicity has been reported in various experimental models. The hsp70s are a family of ubiquitously expressed heat shock proteins. In the recent years, hsp70 has been considered to be one of the candidate genes for predicting cytotoxicity against environmental chemicals. Nowadays emphasis is given to the use of alternatives to mammals in testing, research and education. The European Centre for the Validation of Alternative Methods (EVCAM) has recommended the use of Drosophila as an alternative model for scientific studies. Almost all living organisms possess proteins with a similar structure to that of hsp70s. In the present study, the toxicity of MMS was evaluated by quantifying hsp70 expression and tissue damage in the third instar larvae of transgenic Drosophila melanogaster (hsp70-lacZ) Bg(9), at different doses and hours of exposure. We studied the effect of 0.25, 0.50, 0.75 and 1.0 µl/ml of MMS at 2, 4, 24 and 48 hours of exposure on hsp70 expression by using the soluble O-nitrophenyl-ß-D-galactopyranoside (ONPG) assay and on establishing the tissue damage by the Trypan blue exclusion assay in the third instar larvae of transgenic Drosophila melanogaster (hsp70-lacZ) Bg(9). A dose-dependent increase in the expression of hsp70 was observed at 0.25, 0.50, and 0.75 µl/ml of MMS compared to the control. At the highest dose, i.e. 1.0 µl/ml of MMS, the activity of hsp70 was decreased due to tissue damage.

5.
Nat Prod Res ; 24(12): 1087-94, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-20582805

RESUMO

Antigenotoxic activity of allicin, one of the sulphur compounds of garlic (Allium sativum) which possesses antioxidant and thiol disulphide exchange activity, was studied against estradiol-17beta-induced genotoxic damage using chromosomal aberrations (CAs) and sister chromatid exchanges (SCEs) as parameters. Approximately 10, 20 and 40 microM of estradiol-17beta was tested for its genotoxic effect in the presence of metabolic activation and was found to be genotoxic at 20 and 40 microM. Approximately 20 microM of estradiol-17beta was treated along with 5, 10 and 15 microM of allicin, separately, in the presence of metabolic activation. Similar treatments were given with 40 microM of estradiol-17beta. Treatments along with allicin result in the reduction of CAs and SCEs, suggesting its anti-genotoxic activity in human lymphocytes in vitro against estradiol-17beta-induced genotoxic damage.


Assuntos
Antioxidantes/farmacologia , Estradiol/toxicidade , Ácidos Sulfínicos/farmacologia , Células Cultivadas , Aberrações Cromossômicas/induzido quimicamente , Dissulfetos , Relação Dose-Resposta a Droga , Estrogênios/toxicidade , Feminino , Humanos , Análise de Regressão , Troca de Cromátide Irmã/efeitos dos fármacos , Troca de Cromátide Irmã/genética
6.
Clin Cancer Res ; 16(2): 600-9, 2010 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-20068074

RESUMO

PURPOSE: Ovarian cancer recurrence with the development of paclitaxel resistance is an obstacle to long-term survival. We showed that secretory leukocyte protease inhibitor (SLPI) is a survival factor for ovarian cancer. We hypothesize that SLPI may antagonize paclitaxel injury. EXPERIMENTAL DESIGN: Differential SLPI induction in response to paclitaxel and in response to stable forced expression of SLPI was shown in A2780-1A9 cells and their paclitaxel-resistant sublines, PTX10 and PTX22, and confirmed with HEY-A8 cells. SLPI-mediated survival was reduced by the MAP/extracellular signal-regulated kinase (ERK) kinase inhibitor, U0126, and a humanized neutralizing monoclonal anti-SLPI antibody, CR012. OVCAR3 xenographs tested the role of CR012 in vivo. RESULTS: SLPI expression was lower in A2780-1A9 ovarian cancer cells than in PTX10 and PTX22, and SLPI was induced by paclitaxel exposure. Stable SLPI expression yielded a proliferation advantage (P = 0.01); expression of and response to SLPI in OVCAR3 cells were abrogated by exposure to CR012. SLPI reduced the paclitaxel susceptibility of 1A9 and HEY-A8 cells (P

Assuntos
Carcinoma/patologia , Resistencia a Medicamentos Antineoplásicos/genética , Neoplasias Ovarianas/patologia , Paclitaxel/antagonistas & inibidores , Inibidor Secretado de Peptidases Leucocitárias/fisiologia , Animais , Anticorpos Monoclonais/administração & dosagem , Anticorpos Monoclonais/farmacologia , Anticorpos Monoclonais/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Carcinoma/tratamento farmacológico , Carcinoma/genética , Carcinoma/metabolismo , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/genética , Antagonismo de Drogas , Feminino , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Camundongos , Camundongos SCID , Neoplasias Ovarianas/tratamento farmacológico , Neoplasias Ovarianas/genética , Paclitaxel/farmacologia , Paclitaxel/uso terapêutico , Inibidor Secretado de Peptidases Leucocitárias/genética , Inibidor Secretado de Peptidases Leucocitárias/imunologia , Células Tumorais Cultivadas , Ensaios Antitumorais Modelo de Xenoenxerto
7.
Exp Toxicol Pathol ; 62(5): 503-8, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-19608391

RESUMO

Mitomycin C (MMC) is an antineoplastic agent used to fight a number of different cancers including cancer of the stomach, colon, rectum, pancreas, breast, lung, uterus, cervix, bladder, head, neck, eye and oesophagus. It is a potent DNA cross-linker. The prolonged use of the drug may result in permanent bone marrow damage and other various types of secondary tumors in normal cells. The toxic effect of anticancerous drugs may be reduced if supplemented with natural antioxidants/plant products. With this view, the effect of 5, 10 and 15 microM of curcumin was studied against the genotoxic doses of MMC, i.e. 10 and 20 microM, in cultured human lymphocytes using cell viability, lipid peroxidation and DNA damage quantification as parameters. The treatment of curcumin with MMC results in a significant dose-dependent increase in cell viability and decrease in lipid peroxidation and DNA damage suggesting a protective role of curcumin against the anticancerous drug mitomycin C.


Assuntos
Antibióticos Antineoplásicos/toxicidade , Antioxidantes/farmacologia , Curcumina/farmacologia , Linfócitos/efeitos dos fármacos , Mitomicina/toxicidade , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Fragmentação do DNA/efeitos dos fármacos , Humanos , Peroxidação de Lipídeos/efeitos dos fármacos , Linfócitos/patologia , Masculino
8.
Int J Radiat Biol ; 84(5): 401-12, 2008 May.
Artigo em Inglês | MEDLINE | ID: mdl-18464069

RESUMO

PURPOSE: Velafermin (recombinant human fibroblast growth factor-20, rhFGF-20) has been shown to reduce the severity and duration of mucositis in preclinical acute (single dose) radiation and chemotherapy/radiation models of oral mucositis. Our present study assessed the impact of velafermin on the severity and duration of oral mucositis that occurred as a consequence of fractionated radiation. EXPERIMENTAL DESIGN: Male Golden Syrian hamsters were exposed to eight doses of radiation (7.5 Gy/dose) to the cheek pouch on days 0, 1, 2, 3, 6, 7, 8 and 9 that resulted in severe mucositis. Velafermin (4 mg/kg intraperitoneally) was administered on days 3 and 9; days 2, 3, 8 and 9; days 3, 4, 9 and 10; or days 4, 5, 10 and 11. RESULTS: Although all velafermin-treated groups showed some reduction in the degree of mucositis relative to the vehicle control, the most significant reduction (p < 0.001) was observed in the groups treated on days 3 and 9 or on days 4, 5, 10 and 11. Further histological analysis of resected buccal mucosa revealed improvements in epithelial tissue degradation, connective tissue degradation and inflammation severity after velafermin treatment. Most notably, velafermin treatment reduced inflammatory cytokines interleukin-6 (IL-6) and tumor necrosis factor (TNF) production possibly through nuclear factor-kappaB (NF-kappaB) mediation. The detection of increased NF-E2-related factor-2 (NRF-2) expression in the early onset stage of mucositis in the buccal mucosa suggested additional protective benefits from reactive oxygen species (ROS) generated as a consequence of fractionated radiation treatment. CONCLUSION: Thus, velafermin provided therapeutic benefit in a hamster model of oral mucositis induced by fractionated radiation therapy.


Assuntos
Fatores de Crescimento de Fibroblastos/química , Fatores de Crescimento de Fibroblastos/farmacologia , Mucosa Bucal/patologia , Lesões por Radiação/tratamento farmacológico , Estomatite/tratamento farmacológico , Animais , Bochecha , Cricetinae , Epitélio/efeitos da radiação , Humanos , Inflamação/radioterapia , Interleucina-6/biossíntese , Masculino , Fator 2 Relacionado a NF-E2/biossíntese , NF-kappa B/biossíntese , Fator de Necrose Tumoral alfa/biossíntese
9.
J Nat Med ; 62(1): 52-6, 2008 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-18404342

RESUMO

Nordihydroguaiaretic acid (NDGA), a phenolic lignan, was tested for its antigenotoxic potential against chlormadinone acetate (CMA)-induced genotoxic damage in mice bone-marrow cells. Doses of about 22.50 mg/kg body weight of CMA were given along with 1, 5 and 10 mg/kg body weight of NDGA intraperitoneally. The treatment resulted in the reduction of sister chromatid exchanges and chromosomal aberrations induced by CMA, suggesting an antigenotoxic potential of NDGA. Earlier studies show that CMA generates reactive oxygen species, responsible for genotoxic damage. The free radical-scavenging property of NDGA is responsible for the reduction of genotoxic damage induced by CMA in mice bone-marrow cells.


Assuntos
Antimutagênicos/farmacologia , Células da Medula Óssea/efeitos dos fármacos , Acetato de Clormadinona/toxicidade , Aberrações Cromossômicas/efeitos dos fármacos , Sequestradores de Radicais Livres/farmacologia , Masoprocol/farmacologia , Mutagênicos/toxicidade , Troca de Cromátide Irmã/efeitos dos fármacos , Animais , Antimutagênicos/administração & dosagem , Células da Medula Óssea/patologia , Relação Dose-Resposta a Droga , Feminino , Sequestradores de Radicais Livres/administração & dosagem , Injeções Intraperitoneais , Masoprocol/administração & dosagem , Camundongos
10.
Int J Cancer ; 122(6): 1400-10, 2008 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-18027850

RESUMO

Histone deacetylase inhibitors (HDACi) represent a promising new class of anticancer agents. In the current investigation, we examined the activity of the HDACi belinostat in preclinical models of prostate cancer. In vitro proliferation assays demonstrated that belinostat potently inhibited the growth of prostate cancer cell lines (IC(50) < 1.0 microM) and was cytotoxic to these cells. Washout experiments indicated that exposure to belinostat for relatively short periods of time (<12 hr) induced suboptimal growth-inhibition and that cells exposed to 1.0 microM belinostat for 48 hr retained the capacity for regrowth following drug withdrawal, while cells exposed to 4.0 microM belinostat were irreversibly growth-inhibited. Cell cycle analyses demonstrated that belinostat induced G2/M arrest and increased the percentage of cells with subG1 DNA content, thus confirming the growth-inhibitory and cytotoxic effects of this compound. Normal prostate epithelial cells were generally less susceptible to the effects of belinostat than were prostate cancer cells. In an orthotopic prostate cancer tumor model, belinostat inhibited tumor growth by up to 43%. Moreover, metastatic lung lesions were present in 47% of vehicle-treated animals but in none of the animals administered belinostat. Consistent with its observed antimetastatic activity, belinostat inhibited the migration of prostate tumor cells and increased the production of tissue inhibitor of metalloproteinase-1 (TIMP-1) by these cells, the latter effect being replicated by siRNA knockdown of HDAC3. Belinostat also increased the expression of p21 and decreased the expression of potentially oncogenic proteins (mutant p53 and ERG). These results support the clinical evaluation of belinostat for the treatment of prostate cancer.


Assuntos
Inibidores Enzimáticos/uso terapêutico , Inibidores de Histona Desacetilases , Ácidos Hidroxâmicos/uso terapêutico , Neoplasias da Próstata/tratamento farmacológico , Animais , Divisão Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Inibidores Enzimáticos/farmacologia , Ácidos Hidroxâmicos/farmacologia , Masculino , Camundongos , Camundongos Nus , Neoplasias da Próstata/enzimologia , Neoplasias da Próstata/patologia , Sulfonamidas
11.
Toxicol In Vitro ; 22(1): 10-7, 2008 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-17719740

RESUMO

The majority of the Indian population use traditional natural preparations derived from plant material for the treatment of various diseases, and for that reason it becomes necessary to assess the mutagenic potential or modulating action of plants extract when associated with other substances. The genotoxicity testing provides human a risk assessment. Earlier in vitro and in vivo studies reveal that the plant extracts from various parts of the plant play a modulating role in xenobiotic effects. Identification and characterization of some active principles may lead to the development of the strategies to reduce the risk for developing cancer in humans. Cyproterone acetate (CPA), a synthetic progestin is not only a genotoxic agent but also a tumor initiating agent. It is used in oral contraceptives formulations and also in the treatment of various sexual and metabolic disorders. In this context, the antigenotoxic effect of Centella asiatica L. extract was studied against the genotoxic effect induced by CPA on human lymphocytes using chromosomal aberrations and sister chromatid exchanges as parameters. The treatment of the two doses of CPA, i.e. 20 and 30 microM was given along with the C. asiatica extract at the dosages of 1.075 x 10(-4), 2.125 x 10(-4), 3.15 x 10(-4) and 4.17 x 0(-4)g/ml of culture medium. A clear dose dependent decrease in the genotoxic damage of CPA was observed, suggesting a protective role of C. asiatica extract during CPA therapy. The results of the present study suggest that the plant extract per se do not have genotoxic potential, but can modulate the genotoxicity of CPA on human lymphocytes in vitro.


Assuntos
Antagonistas de Androgênios/toxicidade , Centella/química , Acetato de Ciproterona/toxicidade , Mutagênicos/toxicidade , Extratos Vegetais/farmacologia , Antagonistas de Androgênios/administração & dosagem , Antimutagênicos/administração & dosagem , Antimutagênicos/farmacologia , Células Cultivadas , Aberrações Cromossômicas/efeitos dos fármacos , Acetato de Ciproterona/administração & dosagem , Relação Dose-Resposta a Droga , Humanos , Índia , Linfócitos/efeitos dos fármacos , Linfócitos/metabolismo , Testes de Mutagenicidade , Mutagênicos/administração & dosagem , Extratos Vegetais/administração & dosagem , Troca de Cromátide Irmã/efeitos dos fármacos
12.
J Transl Med ; 5: 49, 2007 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-17935615

RESUMO

BACKGROUND: Treatment options for patients with recurrent superficial bladder cancer are limited, necessitating aggressive exploration of new treatment strategies that effectively prevent recurrence and progression to invasive disease. We assessed the effects of belinostat (previously PXD101), a novel histone deacetylase inhibitor, on a panel of human bladder cancer cell lines representing superficial and invasive disease, and on a transgenic mouse model of superficial bladder cancer. METHODS: Growth inhibition and cell cycle distribution effect of belinostat on 5637, T24, J82, and RT4 urothelial lines were assessed. Ha-ras transgenic mice with established superficial bladder cancer were randomized to receive either belinostat or vehicle alone, and assessed for bladder weight, hematuria, gene expression profiling, and immunohistochemistry (IHC). RESULTS: Belinostat had a significant linear dose-dependent growth inhibition on all cell lines (IC50 range of 1.0-10.0 microM). The 5637 cell line, which was derived from a superficial papillary tumor, was the most sensitive to treatment. Belinostat (100 mg/kg, intraperitoneal, 5 days each week for 3 weeks) treated mice had less bladder weight (p < 0.05), and no hematuria compared with 6/10 control mice that developed at least one episode. IHC of bladder tumors showed less cell proliferation and a higher expression of p21WAF1 in the belinostat-treated mice. Gene expression profile analysis revealed 56 genes significantly different in the treated group; these included the upregulation of p21WAF1, induction of core histone deacetylase (HDAC), and cell communication genes. CONCLUSION: Our data demonstrate that belinostat inhibits bladder cancer and supports the clinical evaluation of belinostat for the treatment of patients with superficial bladder cancer.


Assuntos
Inibidores Enzimáticos/farmacologia , Inibidores de Histona Desacetilases , Ácidos Hidroxâmicos/farmacologia , Neoplasias da Bexiga Urinária/enzimologia , Neoplasias da Bexiga Urinária/patologia , Animais , Comunicação Celular/efeitos dos fármacos , Comunicação Celular/genética , Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Inibidor de Quinase Dependente de Ciclina p21/genética , Ensaios de Seleção de Medicamentos Antitumorais , Inibidores Enzimáticos/efeitos adversos , Feminino , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Hematúria/complicações , Humanos , Ácidos Hidroxâmicos/efeitos adversos , Imuno-Histoquímica , Masculino , Camundongos , Camundongos Transgênicos , Tamanho do Órgão/efeitos dos fármacos , Sulfonamidas , Neoplasias da Bexiga Urinária/complicações , Neoplasias da Bexiga Urinária/genética
13.
Mol Cancer Ther ; 6(1): 37-50, 2007 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-17237265

RESUMO

Histone deacetylase inhibitors (HDI) can inhibit proliferation and enhance apoptosis in a wide range of malignancies. However, HDIs show relatively modest activity in head and neck squamous cell carcinomas (HNSCC), in which we have shown the activation of nuclear factor-kappaB (NF-kappaB; NF-kappaB1/RelA or p50/p65), a transcription factor that promotes expression of proliferative and antiapoptotic genes. In this study, we examined if HDIs enhance activation of NF-kappaB and target genes and if genetic or pharmacologic inhibition of NF-kappaB can sensitize HNSCC to HDIs. Limited activity of classic HDIs trichostatin A and sodium butyrate was associated with enhanced activation of NF-kappaB reporter activity in a panel of six HNSCC cell lines. HDIs enhanced NF-kappaB p50/p65 DNA binding and acetylation of the RelA p65 subunit. Transfection of small interfering RNAs targeting p65 strongly inhibited NF-kappaB expression and activation, induced cell cycle arrest and cell death, and further sensitized HNSCC cells when combined with HDIs. The p65 small interfering RNA inhibited HDI-enhanced expression of several NF-kappaB-inducible genes implicated in oncogenesis of HNSCC, such as p21, cyclin D1, and BCL-XL. Bortezomib, an inhibitor of proteasome-dependent NF-kappaB activation, also increased sensitization to trichostatin A, sodium butyrate, and a novel HDI, PXD101, in vitro, and to the antitumor effects of PXD101 in bortezomib-resistant UMSCC-11A xenografts. However, gastrointestinal toxicity, weight loss, and mortality of the combination were dose limiting and required parenteral fluid administration. We conclude that HDI-enhanced NF-kappaB activation is one of the major mechanisms of resistance of HNSCC to HDIs. The combination of HDI and proteasome inhibitor produced increased antitumor activity. Low starting dosages for clinical studies combining HDIs with proteasome inhibitors and IV fluid support may be warranted.


Assuntos
Ácidos Borônicos/uso terapêutico , Carcinoma de Células Escamosas/tratamento farmacológico , Neoplasias de Cabeça e Pescoço/tratamento farmacológico , Ácidos Hidroxâmicos/uso terapêutico , Inibidores de Proteassoma , Pirazinas/uso terapêutico , RNA Interferente Pequeno/metabolismo , Fator de Transcrição RelA/metabolismo , Acetilação/efeitos dos fármacos , Animais , Antineoplásicos/administração & dosagem , Antineoplásicos/farmacologia , Protocolos de Quimioterapia Combinada Antineoplásica , Ácidos Borônicos/administração & dosagem , Ácidos Borônicos/farmacologia , Bortezomib , Carcinoma de Células Escamosas/patologia , Ciclina D1/genética , Inibidor de Quinase Dependente de Ciclina p21/genética , DNA de Neoplasias/metabolismo , Regulação para Baixo/efeitos dos fármacos , Resistencia a Medicamentos Antineoplásicos , Inibidores Enzimáticos/farmacologia , Neoplasias de Cabeça e Pescoço/enzimologia , Neoplasias de Cabeça e Pescoço/patologia , Inibidores de Histona Desacetilases , Humanos , Ácidos Hidroxâmicos/administração & dosagem , Ácidos Hidroxâmicos/farmacologia , Proteínas Inibidoras de Apoptose/genética , Camundongos , Camundongos SCID , Subunidade p50 de NF-kappa B/metabolismo , Ligação Proteica/efeitos dos fármacos , Pirazinas/administração & dosagem , Pirazinas/farmacologia , Sulfonamidas , Ensaios Antitumorais Modelo de Xenoenxerto , Proteína bcl-X/metabolismo
14.
Mol Cancer Ther ; 5(8): 2086-95, 2006 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-16928830

RESUMO

Histone deacetylase inhibitors represent a promising new class of anticancer agents. In the current investigation, we examined the activity of PXD101, a potent histone deacetylase inhibitor, used alone or in combination with clinically relevant chemotherapeutics (docetaxel, paclitaxel, and carboplatin), in preclinical in vitro and in vivo models of ovarian cancer. In vitro activity was examined in ovarian cancer and multidrug-resistant cell lines grown in monolayer culture, and in primary clinical ovarian cancer specimens grown in three-dimensional organoid culture. PXD101 was found to inhibit in vitro cancer cell growth at sub- to low micromolar IC(50) potency, exhibited synergistic activity when used in combination with relevant chemotherapeutics, and effectively inhibited the growth of multidrug-resistant cells. In vivo, PXD101 displayed single-agent antitumor activity on human A2780 ovarian cancer s.c. xenografts which was enhanced via combination therapy with carboplatin. In support of these findings, PXD101 was shown to increase the acetylation of alpha-tubulin induced by docetaxel and the phosphorylation of H2AX induced by carboplatin. Taken together, these results support the clinical evaluation of PXD101 used alone or in combination therapy for the treatment of ovarian cancer.


Assuntos
Inibidores Enzimáticos/farmacologia , Inibidores de Histona Desacetilases , Ácidos Hidroxâmicos/farmacologia , Neoplasias Ovarianas/tratamento farmacológico , Acetilação , Animais , Protocolos de Quimioterapia Combinada Antineoplásica , Carboplatina/administração & dosagem , Linhagem Celular Tumoral , Docetaxel , Resistência a Múltiplos Medicamentos , Resistencia a Medicamentos Antineoplásicos , Ensaios de Seleção de Medicamentos Antitumorais , Feminino , Histonas/efeitos dos fármacos , Histonas/metabolismo , Humanos , Ácidos Hidroxâmicos/administração & dosagem , Camundongos , Camundongos Nus , Neoplasias Ovarianas/patologia , Fosforilação , Sulfonamidas , Taxoides/administração & dosagem , Taxoides/farmacologia , Tubulina (Proteína)/efeitos dos fármacos , Tubulina (Proteína)/metabolismo
15.
J Health Popul Nutr ; 23(4): 320-30, 2005 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-16599102

RESUMO

This prospective randomized trial was carried out to test the efficacy of a specific intervention for reducing the extent of their malnutrition and to change behaviour of mothers relating to child-feeding practices, care-giving, and health-seeking practices under the Bangladesh Integrated Nutrition Project (BINP). The study was conducted in rural Bangladesh among 282 moderately-malnourished (weight-for-age between 61% and 75% of median of the National Center for Health Statistics standard) children aged 6-24 months. Mothers of the first intervention group received intensive nutrition education (INE group) twice a week for three months. The second intervention group received the same nutrition education, and their children received additional supplementary feeding (INE+SF group). The comparison group received nutrition education from the community nutrition promoters twice a month according to the standard routine service of BINP. The children were observed for a further six months. After three months of interventions, a significantly higher proportion of children in the INE and INE+SF groups improved (37% and 47% respectively) from moderate to mild or normal nutrition compared to the comparison group (18%) (p < 0.001). At the end of six months of observation, the nutritional status of children in the intervention groups improved further from moderate to mild or normal nutrition compared to the comparison group (59% and 86% vs 30%, p < 0.0001). As the intensive nutrition education and supplementation given were highly effective, more children improved from moderate malnutrition to mild or normal nutritional status despite a higher incidence of morbidity. The frequency of child feeding and home-based complementary feeding improved significantly (p < 0.001) in both the intervention groups after three months of interventions and six months of observation. Body-weight gain was positively associated with age, length-for-age, weight-for-length, frequency of feeding of khichuri, egg, and potato (p < 0.05). Ability of mothers to identify malnutrition improved from 15% to 99% in the INE group and from 15% to 100% in the INE+SF group, but reduced from 24% to 21% in the comparison group. Use of separate feed pots, frequency of feeding, and cooking of additional complementary feeds improved significantly in the INE and INE+SF groups compared to the comparison group after three months of interventions and six months of observation. It can be concluded from the findings of the study that intensive nutrition education significantly improves the status of moderately-malnourished children with or without supplementary feeding.


Assuntos
Transtornos da Nutrição Infantil/epidemiologia , Alimentos Fortificados/estatística & dados numéricos , Mães/educação , Ciências da Nutrição/educação , Estado Nutricional/fisiologia , Análise de Variância , Bangladesh/epidemiologia , Transtornos da Nutrição Infantil/prevenção & controle , Ciências da Nutrição Infantil/educação , Pré-Escolar , Feminino , Promoção da Saúde/métodos , Humanos , Lactente , Masculino , Estudos Prospectivos , População Rural/estatística & dados numéricos , Análise de Sobrevida , Fatores de Tempo , Resultado do Tratamento
16.
Int J Cancer ; 103(4): 501-7, 2003 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-12478666

RESUMO

We have characterized a receptor:ligand pair, ICOS:B7RP-1, that is structurally and functionally related to CD28:B7.1/2. We reported previously that B7RP-1 costimulates T cell proliferation and immune responses (Yoshinaga et al., Nature 1999;402:827-32; Guo et al., J Immunol 2001;166:5578-84; Yoshinaga et al., Int Immunol 2000;12:1439-47). We report that B7RP-1-Fc causes rejection or growth inhibition of Meth A, SA-1 and EMT6 tumors in syngeneic mice. Established Meth A tumors were rejected effectively with a single dose of B7RP-1-Fc, however, the treatment was less effective on larger tumors. Mice that rejected Meth A tumors previously by Day 30, also rejected a subsequent Meth A challenge on Day 60, without additional B7RP-1-Fc treatment, indicating a long-lived memory response. Tumor cells believed to be less immunogenic, such as P815 and EL-4 cells, were less responsive to this treatment. The EL-4 responsiveness to the B7RP-1-Fc treatment was enhanced, however, by pre-treatment of the mice with cyclophosphamide. As expected, T cells appeared to be targeted by B7RP-1-Fc treatment. Thus, the administration of soluble B7RP-1-Fc may have therapeutic value in generating or enhancing anti-tumor activity in a clinical setting.


Assuntos
Antígeno B7-1/uso terapêutico , Neoplasias/terapia , Animais , Antígenos CD/farmacologia , Antineoplásicos/uso terapêutico , Antineoplásicos Alquilantes/farmacologia , Antígeno B7-2 , Complexo CD3/biossíntese , Divisão Celular/efeitos dos fármacos , Ciclofosfamida/uso terapêutico , Citocinas/biossíntese , Relação Dose-Resposta a Droga , Feminino , Imuno-Histoquímica , Ligante Coestimulador de Linfócitos T Induzíveis , Ligantes , Glicoproteínas de Membrana/farmacologia , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos DBA , Camundongos Nus , Transplante de Neoplasias , Fatores de Tempo , Células Tumorais Cultivadas
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