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1.
Indian J Pharmacol ; 46(2): 181-4, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24741190

RESUMO

AIM: Two recurrent cases of severe acute liver injury attributed to the use of a wild germander decoction, prepared with some variation in traditional method has been reported. The aim of the present study was to correlate the hepatotoxic effect observed in patients who consumed germander decoction with teucrin A levels. Antioxidant properties were analyzed to assess any possible differences between the decoction used traditionally by the family (without negative consequences) and the decoction taken by the patients. MATERIALS AND METHODS: Different types of germander decoctions were prepared in the laboratory by simulating the same conditions for preparing the decoction by the patients and their family members. The levels of teucrin A, the polyphenols and the antioxidant power were determined. One-way analysis of variance was used to test for differences between the groups. RESULTS AND CONCLUSIONS: The extract consumed by the patients had higher concentration of teucrin A, lower antioxidant activity and lower content of polyphenols compared with the traditional decoction, revealing an inverse relationship between teucrin A content and antioxidant capacity. These case reports emphasize that more information is needed on the safety and quality of these natural products.


Assuntos
Doença Hepática Induzida por Substâncias e Drogas/etiologia , Extratos Vegetais/isolamento & purificação , Extratos Vegetais/toxicidade , Teucrium/toxicidade , Idoso , Doença Hepática Induzida por Substâncias e Drogas/diagnóstico , Composição de Medicamentos/métodos , Feminino , Humanos , Itália , Masculino , Pessoa de Meia-Idade , Componentes Aéreos da Planta/química , Componentes Aéreos da Planta/crescimento & desenvolvimento , Estações do Ano , Teucrium/química , Teucrium/crescimento & desenvolvimento
2.
Int J Clin Pharmacol Ther ; 50(4): 302-6, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22456302

RESUMO

OBJECTIVE: Although hypoglycemia is known to be associated with levofloxacin, patients are continually being hospitalized because of this adverse event. Here we have reported two further cases of severe hypoglycemia and discussed the possibility that the hypoglycemia is the result of interactions between levofloxacin and certain drugs, in order to alert physicians to be aware that geriatric patients, particularly those with Type 2 diabetes and in polytherapy, are at risk of showing this adverse reaction. CASES SUMMARY: A 91-year-old woman with Type 2 diabetes on metformin and glibenclamide, also under treatment with oral antihypertensive drugs, platelet antiaggregant, low-molecular- weight heparin and buprenorphine, was prescribed levofloxacin for a bacterial infection. Liver function and renal function parameters were within normal limits. After repeated administration of levofloxacin, her serum glycemic levels had decreased to 47 mg/dl and the patient was in a coma. After stopping levofloxacin her glycemia level returned to the normal value. A 61 year-old male, affected by tonsillar squamous cell carcinoma, with Type 2 diabetes on metformin and glibenclamide, under treatment with low-molecular-weight heparin for deep venous thrombosis, hydromorphone and undergoing nutritional support, was treated with levofloxacin for a bacterial infection. After 72 h the patient was unresponsive and his blood glucose levels were 38 mg/dl. After discontinuation of levofloxacin administration the patient was treated with glucose infusion and his glycemic values gradually returned to the normal range. DISCUSSION: The causality relationship between the levofloxacin and the hypoglycemia was established using Naranjo's ADR probability scale. These case reports confirm the literature data that serious hypoglycemia may develop due to the use of levofloxacin and appears to occur most frequently in elderly patients with Type 2 diabetes who are receiving oral hypoglycemic agents. We described the possible pharmacokinetic and pharmacodinamic mechanisms of the interaction between levofloxacin and the other drugs. CONCLUSIONS: We hypothesized that the concomitant use of several drugs and particularly levofloxacin in association with oral antidiabetic drugs, opioid analgesics and low-molecular-weight heparin could concur to cause this side effect. The safety and tolerability of this anti-infective agent should be revised urgently.


Assuntos
Antibacterianos/efeitos adversos , Glicemia/efeitos dos fármacos , Diabetes Mellitus Tipo 2/tratamento farmacológico , Hipoglicemia/induzido quimicamente , Hipoglicemiantes/efeitos adversos , Levofloxacino , Ofloxacino/efeitos adversos , Idoso de 80 Anos ou mais , Diabetes Mellitus Tipo 2/sangue , Diabetes Mellitus Tipo 2/complicações , Interações Medicamentosas , Feminino , Humanos , Hipoglicemia/sangue , Hipoglicemia/diagnóstico , Masculino , Pessoa de Meia-Idade , Polimedicação , Medição de Risco , Índice de Gravidade de Doença
3.
Eur J Med Chem ; 46(6): 2206-16, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21440338

RESUMO

Serotonin (5-hydroxytryptamine, 5-HT) is one of the most important neuromediator involved in numerous physiological and pathophysiological processes. In addition it is well established that 5-HT acts as a growth factor on several types of non-tumoral and tumoral cells, and recently it was also related to oncogenes. 5-HT1A receptor expression was identified in prostatic tumor cell lines (PC3 cells) and in human hormone refractory prostate cancer tissue. Based on these observations, development of 5-HT1A antagonists could be useful in inhibiting the growth of cancer cells. In order to investigate on potential use of 5-HT1A ligands as antiproliferative agents, we have analyzed a new set of 1-naphtylpiperazine derivatives. In binding studies, several molecules showed affinity in nanomolar and subnanomolar range at 5-HT1A and moderate to no affinity for other relevant receptors (5-HT2A, 5-HT2C, D1, D2, α1 and α2). All compounds were then evaluated in order to assess their antiproliferative activity using PC3 cells and the most active compounds (1 and 2) were fully characterized to define the mechanism responsible for the observed antiproliferative effect.


Assuntos
Antineoplásicos/farmacologia , Naftalenos/farmacologia , Piperazinas/farmacologia , Neoplasias da Próstata/tratamento farmacológico , Receptor 5-HT1A de Serotonina/metabolismo , Antineoplásicos/síntese química , Antineoplásicos/química , Ciclo Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Ligantes , Masculino , Estrutura Molecular , Naftalenos/síntese química , Naftalenos/química , Piperazinas/síntese química , Piperazinas/química , Neoplasias da Próstata/metabolismo , Neoplasias da Próstata/patologia , Receptor 5-HT1A de Serotonina/biossíntese , Estereoisomerismo , Relação Estrutura-Atividade , Células Tumorais Cultivadas
4.
Plant Foods Hum Nutr ; 66(1): 11-6, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21290188

RESUMO

Antioxidant activity of fresh Allium sativum L. (garlic) is well known and is mainly due to unstable and irritating organosulphur compounds. Fresh garlic extracted over a prolonged period (up to 20 months) produces odourless aged garlic extract (AGE) containing stable and water soluble organosulphur compounds that prevent oxidative damage by scavenging free radicals. The aim of this study was to investigate the in vitro antioxidant activity of aged (up to 20 months) 15% hydroethanolic extracts of different parts (bulbs, bulblets, flower bulblets, flowers, and leaves) of three Allium spontaneous species which are endemic for Italian flora: Allium neapolitanum Cyr., Allium subhirsutum L., Allium roseum L. and to compare it with the in vitro antioxidant activity of aged 15% hydroethanolic extracts of bulbs and leaves of garlic. The antioxidant potential of aged extracts of all species has been evaluated using two different spectrophotometric assays: 2,2-diphenylpicrylhydrazyl (DPPH) test and the ferric reducing/antioxidant power (FRAP) assay. Furthermore the polyphenol content was determined. The aged extracts obtained from the leaves showed the best antioxidant activity, followed by flowers and then by bulbs in both used tests, while flower bulblets and bulblets exhibited lower results or no activity. The polyphenol content was generally directly correlated with antioxidant/antiradical activity. This study confirms the data obtained in previous researches, the wild-type species of Allium and in particular organs other than bulbs are more active and efficacious than garlic bulb. Surely leaves of these Allium spp. deserve special attention.


Assuntos
Antioxidantes/análise , Flavonoides/análise , Alho/química , Fenóis/análise , Extratos Vegetais/química , Antioxidantes/química , Compostos de Bifenilo , Flavonoides/química , Flores/química , Fenóis/química , Picratos , Extratos Vegetais/análise , Folhas de Planta/química , Raízes de Plantas/química , Polifenóis
5.
Phytother Res ; 21(9): 874-8, 2007 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-17514631

RESUMO

The genus Allium (Alliaceae) is an important dietary source of antioxidant phytochemical products. The antioxidant activity of some Allium species is well known but no information is available on the in vitro antioxidant activities of Italian Allium species growing wild. The aim of this study was to examine the in vitro antioxidant activity of aqueous extracts of different parts belonging to three Allium species growing wild, endemic to Italian flora: Allium neapolitanum Cyr., Allium subhirsutum L. and Allium roseum L., compared with the in vitro antioxidant activity of aqueous extracts of bulbs and leaves of the greatly studied garlic (Allium sativum L.). The antioxidant potential of extracts was evaluated using two different spectrophotometric assays: the DPPH test and FRAP assay. Furthermore the polyphenolic content was determined in all Allium species. The flowers of species growing wild showed the higher antioxidant power. Interesting results were shown even by the leaves, while the antioxidant capacity of the bulbs was lower. A correlation between the phenolic contents and the antioxidant activity was discovered. The differences in antioxidant capacity reflect the variability in the Allium species and the parts of the plant used and that the bulb of Allium sativum did not show higher antioxidant power.


Assuntos
Allium , Antioxidantes/química , Fitoterapia , Extratos Vegetais/química , Compostos de Bifenilo , Etnobotânica , Flavonoides/química , Flores , Humanos , Itália , Fenóis/química , Picratos/química , Folhas de Planta , Polifenóis
6.
J Cell Mol Med ; 11(1): 156-70, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17367510

RESUMO

BACKGROUND: To investigate the cardiotoxic role of reactive oxygen species (ROS) and of products derived from catecholamines auto-oxidation, we studied: (1) the response of antioxidant cardiac cellular defence systems to oxidative stress induced by norepinephrine (NE) administration, (2) the effect of NE administration on cardiac beta1-adrenergic receptors by means of receptor binding assay, (3) the cellular morphological alterations related to the biologically cross-talk between the NE administration and cytokines [tumor necrosis factor-alpha (TNF-alpha), monocyte chemotactic protein-1 (MCP-1), interleukins IL6, IL8, IL10]. METHODS AND RESULTS: A total of 195 male rats was used in the experiment. All animals underwent electrocardiogram (EKG) before being sacrificed. The results obtained show that NE administration influences the antioxidant cellular defence system significantly increasing glutathione peroxidase (GPx) activity, glutathione reductase (GR) and superoxide dismutase (SOD). The oxidized glutathione (GSH/GSSG) ratio significantly decreases and malondialdehyde (MDA) levels increase showing a state of lipoperoxidation of cardiac tissue. We describe a significant apoptotic process randomly sparse in the damaged myocardium and the effect of ROS on the NE-mediated TNF-alpha, MCP-1, and IL6, IL8, IL10 production. CONCLUSIONS: Our results support the hypothesis that catecholamines may induce oxidative damage through reactive intermediates resulting from their auto-oxidation, irrespective of their interaction with adrenergic receptors, thus representing an important factor in the pathogenesis of catecholamines-induced cardiotoxicity. The rise of the cardioinhibitory cytokines may be interpreted as the adaptive response of jeopardized myocardium with respect to the cardiac dysfunction resulting from NE injection.


Assuntos
Agonistas alfa-Adrenérgicos/farmacologia , Miocárdio/metabolismo , Miocárdio/patologia , Norepinefrina/farmacologia , Estresse Oxidativo/efeitos dos fármacos , Agonistas alfa-Adrenérgicos/administração & dosagem , Animais , Apoptose/efeitos dos fármacos , Citocinas/metabolismo , Esquema de Medicação , Eletrocardiografia , Dissulfeto de Glutationa/metabolismo , Glutationa Peroxidase/metabolismo , Glutationa Redutase/metabolismo , Imuno-Histoquímica , Peroxidação de Lipídeos/efeitos dos fármacos , Masculino , Malondialdeído/análise , Miocárdio/enzimologia , Norepinefrina/administração & dosagem , Ratos , Ratos Wistar , Espécies Reativas de Oxigênio/metabolismo , Receptor Cross-Talk/efeitos dos fármacos , Receptores Adrenérgicos beta 1/metabolismo , Superóxido Dismutase/metabolismo
7.
Phytother Res ; 20(8): 701-3, 2006 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-16676297

RESUMO

This study was designed to examine the in vitro antiproliferative activity of the methanol crude extracts of six Salvia species: Salvia dominica L. leaves, Salvia lanigera Desf. aerial parts, Salvia menthaefolia Ten. roots, Salvia palaestina Benth. aerial parts, Salvia sclarea L. roots and Salvia spinosa L. aerial parts. Extracts were screened for their possible antitumoral activity by MTT test on nine human cancer cell lines: glioblastoma (DBTRG-05MG, T98G, U-87MG), colorectal adenocarcinoma (WiDr and HT-29), prostate adenocarcinoma (MDA Pca2b), choriocarcinoma (JEG-3), endometrium adenocarcinoma (HEC-1A) and B lymphoblast (CIR). IC(50) values were determined for only five extracts and ranged from 90 to 400 microg/mL approximately. Salvia menthaefolia extract exhibited marked antiproliferative activity against all tumor cell lines showing lower IC(50) values, while S. spinosa, S. sclarea and S. dominica extracts showed a degree cytotoxic activity dependent on the cell line type. Finally S. palaestina extract revealed a moderate antiproliferative effect only against three cell lines. Salvia lanigera extract displayed toxic activity at all concentrations tested. The results strengthen the evidence that the genus Salvia could be considered a natural resource of potential antitumor agents.


Assuntos
Antineoplásicos/farmacologia , Proliferação de Células/efeitos dos fármacos , Fitoterapia , Extratos Vegetais/farmacologia , Salvia , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Concentração Inibidora 50
8.
Invest New Drugs ; 24(2): 99-110, 2006 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-16502353

RESUMO

Advanced colorectal cancer is a common disease with an high mortality rate. For four decades, pharmacological treatment of the advanced disease was based on the use of 5-fluorouracil alone or in combination with biomodulators such as folinic acid and intereferon alpha. In the last 5 years, response to therapy has been considerably ameliorated thanks to the discovery of new drugs such as oxaliplatin and CPT-11. These agents, in combination with 5-fluorouracil, according to various schedules of treatment, have reached a significant improvement of palliation, response rate and survival. Immunotherapy is an uprising modality of treatment for human cancer including colorectal carcinoma. Its rationale is based on the knowledge that tumour cells are genetically unstable and produce molecular structures which allow their recognition and destruction by the immune-surveillance system. Therefore, humoral as well as cellular compartments of the immune system can be utilized according to a "passive" strategy (e.g. monoclonal antibody administration and adoptive immunotherapy) or an "active" approach, by using different modalities of vaccine therapy. In this context, monoclonal antibodies (mAbs) and cancer vaccines are being tested for the treatment of advanced colorectal cancer. Due to their genetic instability and extraordinary adaptative potential, tumour cells may acquire resistance to the immune effectors and mAbs exactly as they do for cytotoxic drugs. To improve the results of both immunological and chemical modality of cancer treatment, an increasing number of authors is starting to combine chemo and immunotherapy in the attempt to circumvent the limitations of both strategies. This report tries to review the possible rationale of the chemo-immunotherapy combination, illustrating preliminary results of preclinical and clinical studies.


Assuntos
Adjuvantes Imunológicos/uso terapêutico , Anticorpos Monoclonais/uso terapêutico , Antineoplásicos/uso terapêutico , Vacinas Anticâncer/uso terapêutico , Neoplasias Colorretais/terapia , Imunização Passiva , Imunoterapia Ativa , Animais , Cisplatino/uso terapêutico , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/imunologia , Terapia Combinada , Citocinas/uso terapêutico , Fluoruracila/uso terapêutico , Humanos
9.
J Clin Oncol ; 23(35): 8950-8, 2005 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-16061910

RESUMO

PURPOSE: Tumor cell killing by anticancer drugs may be supported by their immuno- and pharmacologic effects. Chemotherapy is in fact able to (A) upregulate tumor-associated antigen expression, including carcinoembryonic antigen (CEA) or other target molecules such as thymidylate synthase (TS); and (B) downregulate tumor cell resistance to the death signals induced by tumor antigen-specific cytotoxic T lymphocytes. This provides the rationale for combining chemo- and immunotherapy. MATERIALS AND METHODS: We describe the results of a translational phase II trial designed to evaluate the toxicity, antitumor activity and immunologic effects of gemcitabine + FOLFOX-4 (oxaliplatin, fluorouracil, and folinic acid) polychemotherapy followed by the subcutaneous administration of granulocyte macrophage colony-stimulating factor and low-dose interleukin-2 in colorectal carcinoma patients. The study involved 29 patients (16 males and 13 females with a mean age of 69 years), 21 of whom had received a previous line of treatment, and 19 had liver involvement. RESULTS: The treatment was well tolerated and induced very high objective response (68.9%) and disease control rates (96.5%), with an average time to progression of 12.5 months. An immunologic study of peripheral blood mononuclear cells (PBMCs) taken from 20 patients showed an enhanced proliferative response to colon carcinoma antigen and a significant reduction in suppressive regulatory T lymphocytes (CD4+CD25T-reg+). A cytofluorimetric study of the PBMCs of five HLA-A(*)02.01+ patients who achieved an objective response showed an increased frequency of cytolytic T lymphocyte precursors specific for known CEA- and TS-derived epitopes. CONCLUSION: The results show that our regimen has strong immunologic and antitumor activity in colorectal cancer patients and deserves to be investigated in phase III trials.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias do Colo/tratamento farmacológico , Neoplasias Colorretais/tratamento farmacológico , Fator Estimulador de Colônias de Granulócitos e Macrófagos/uso terapêutico , Imunoterapia/métodos , Idoso , Antígenos de Neoplasias/imunologia , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Antígeno Carcinoembrionário/imunologia , Neoplasias do Colo/imunologia , Neoplasias do Colo/secundário , Neoplasias Colorretais/imunologia , Neoplasias Colorretais/patologia , Citotoxicidade Imunológica/efeitos dos fármacos , Desoxicitidina/administração & dosagem , Desoxicitidina/efeitos adversos , Desoxicitidina/análogos & derivados , Progressão da Doença , Feminino , Citometria de Fluxo , Fluoruracila/administração & dosagem , Fluoruracila/efeitos adversos , Fator Estimulador de Colônias de Granulócitos e Macrófagos/administração & dosagem , Fator Estimulador de Colônias de Granulócitos e Macrófagos/efeitos adversos , Humanos , Infusões Intravenosas , Interleucina-2/administração & dosagem , Interleucina-2/efeitos adversos , Leucovorina/administração & dosagem , Leucovorina/efeitos adversos , Masculino , Compostos Organoplatínicos/administração & dosagem , Compostos Organoplatínicos/efeitos adversos , Oxaliplatina , Linfócitos T Reguladores/efeitos dos fármacos , Linfócitos T Reguladores/imunologia , Timidilato Sintase/imunologia , Resultado do Tratamento , Gencitabina
10.
J Immunol ; 175(2): 820-8, 2005 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-16002679

RESUMO

Gemcitabine, oxaliplatin, leucovorin, and 5-fluorouracil (GOLF) is a novel multidrug regimen inducing high levels of necrosis and apoptosis in colon carcinoma cells. This regimen is also able to promote a process of Ag remodeling including up-regulation of immunotherapy targets like carcinoembryonic Ag (CEA), thymidylate synthase (TS). We have conducted a preclinical study aimed to investigate whether these drug-induced modifications would also enhance colon cancer cell immunogenicity. Several CTL lines were thus generated by in vitro stimulating human HLA-A(*)02.01(+) PBMCs, from normal donors and colon cancer patients, with autologous dendritic cells cross-primed with cell lysates of colon cancer cells untreated, irradiated, or previously exposed to different drug treatments including the GOLF regimen. Class I HLA-restricted cytolytic activity of these CTL lines was tested against colon cancer cells and CEA and TS gene transfected target cells. These experiments revealed that CTLs sensitized with GOLF-treated cancer cells were much more effective than those sensitized with the untreated colon carcinoma cells or those exposed to the other treatments. CTL lines sensitized against the GOLF-treated colon cancer cells, also expressed a greater percentage of T-lymphocyte precursors able to recognize TS- and CEA-derived peptides. These results suggest that GOLF regimen is a powerful antitumor and immunomodulating regimen that can make the tumor cells a suitable means to induce an Ag-specific CTL response. These results suggest that a rationale combination of GOLF chemotherapy with cytokine-based immunotherapy could generate a chemotherapy-modulated Ag-specific T-lymphocyte response in cancer patients able to destroy the residual disease survived to the cytotoxic drugs.


Assuntos
Antígenos de Neoplasias/metabolismo , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias do Colo/tratamento farmacológico , Neoplasias do Colo/imunologia , Apresentação Cruzada/imunologia , Citotoxicidade Imunológica/efeitos dos fármacos , Células Dendríticas/imunologia , Linfócitos T Citotóxicos/imunologia , Antígenos de Neoplasias/imunologia , Protocolos de Quimioterapia Combinada Antineoplásica/toxicidade , Linhagem Celular Tumoral , Técnicas de Cocultura , Neoplasias do Colo/patologia , Apresentação Cruzada/efeitos dos fármacos , Células Dendríticas/metabolismo , Desoxicitidina/administração & dosagem , Desoxicitidina/análogos & derivados , Desoxicitidina/uso terapêutico , Desoxicitidina/toxicidade , Avaliação Pré-Clínica de Medicamentos , Fluoruracila/administração & dosagem , Fluoruracila/uso terapêutico , Fluoruracila/toxicidade , Antígenos HLA-A/biossíntese , Antígenos HLA-A/genética , Antígeno HLA-A2 , Células HT29 , Humanos , Leucovorina/administração & dosagem , Leucovorina/uso terapêutico , Leucovorina/toxicidade , Leucócitos Mononucleares/efeitos dos fármacos , Leucócitos Mononucleares/imunologia , Leucócitos Mononucleares/metabolismo , Compostos Organoplatínicos/administração & dosagem , Compostos Organoplatínicos/uso terapêutico , Compostos Organoplatínicos/toxicidade , Oxaliplatina , Linfócitos T Citotóxicos/efeitos dos fármacos , Gencitabina
11.
J Clin Endocrinol Metab ; 90(7): 4205-10, 2005 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-15840756

RESUMO

CONTEXT: Preeclampsia (PE) is a disorder that occurs only during pregnancy. The placenta has a controlling role in this condition. Recent literature suggests that the oxidative stress is a component of PE and plays a main role in the link between decreased placental perfusion and the impaired function of maternal endothelium. OBJECTIVE: Because the human placenta expresses endothelin-1 (ET-1) and its circulating levels are high in pregnancies complicated with PE, the present study investigated the role of ET-1 on placental oxidative stress pathways. DESIGN: Human placental explants, JEG-3, and primary cytotrophoblast cells were cultured with increasing ET-1 concentrations for 6 and 24 h. SETTING: The study was conducted at tertiary clinical care centers in Siena and Padova, Italy. INTERVENTIONS: Human placental explants, JEG-3, and primary cytotrophoblast cells were used to test ET-1 effect. MAIN OUTCOME MEASURE(S): The main outcome measure was ET-1 mRNA and its receptor mRNAs, type A and B, detection by RT-PCR. The common markers of oxidative stress [malondialdehyde (MDA), glutathione (GSH), glutathione disulfide (GSSG), ascorbic acid (AA)] as well as cell proliferation and vitality were measured after stimulation periods. RESULTS: ET-1 inhibits cell proliferation and vitality and triggers oxidative stress in the human placenta by altering the balance between oxidant (increased MDA levels) and antioxidant (decreased GSH, GSSG, and AA) forces in favor of oxidation. CONCLUSIONS: Because MDA damages endothelial cells, whereas GSH, GSSG, and AA protect them, we postulate that ET-1 may be one of the key links between primary placental disorders and the systemic endothelial dysfunction of PE.


Assuntos
Endotelina-1/fisiologia , Estresse Oxidativo , Placenta/metabolismo , Pré-Eclâmpsia/etiologia , Linhagem Celular Tumoral , Feminino , Glutationa/metabolismo , Humanos , Peroxidação de Lipídeos , Gravidez
12.
Int J Cancer ; 104(4): 437-45, 2003 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-12584740

RESUMO

Cancer vaccines directed against tumor associate antigen (TAA) have produced encouraging results in preclinical models but not in cancer patients. A major limitation of this strategy is the relative degree of tolerance to these antigens and the low and heterogeneous tumor cell expression of TAA and major histocompatibility complex (MHC). Previous studies have shown that 5-fluorouracil (5-FU) can upregulate the expression of membrane-associated carcino-embryonic antigen (CEA), and MHC molecules in colon and breast carcinoma cell lines. We have investigated whether this drug can also enhance their sensitivity to the lytic effects of CEA-peptide specific Cytotoxic T cell lymphocytes (CTL). The CEA peptide-specific CTLs generated in our laboratory from normal HLA-A(*)02.01(+) donor PBMCs, were able to kill HLA-A(*)02.01(+)/CEA(+) breast (MCF-7-T103) and colon (HLA-A(*)02.01 gene-transfected HT-29 and C22.20) carcinoma cells in HLA-A(*)02.01 restricted manner. The treatment of target cells with 5-FU, enhanced their CEA expression and susceptibility to CTL-mediated lysis. Cold competition assays confirmed these results, thus supporting the hypothesis that immune target cell lysis and 5-FU mediated enhancement were dependent on CEA peptide presentation by cancer cells. 5-FU treatment of functionally "mature" CTL after in vitro expansion, did not reduce their cytolytic activity against MT-2 target cells but, when the anti-metabolite was added during the immune-sensitization phase, CTL generation was significantly inhibited. These results provide a rationale for investigating a possible new role of 5-FU as an immuno targeting amplifier agent in breast and colorectal cancer patients immunized with CEA-directed cancer vaccines.


Assuntos
Antimetabólitos Antineoplásicos/farmacologia , Neoplasias da Mama/tratamento farmacológico , Antígeno Carcinoembrionário/biossíntese , Neoplasias do Colo/tratamento farmacológico , Citotoxicidade Imunológica/efeitos dos fármacos , Fluoruracila/farmacologia , Antígenos HLA-A/imunologia , Linfócitos T Citotóxicos/imunologia , Neoplasias da Mama/imunologia , Antígeno Carcinoembrionário/imunologia , Neoplasias do Colo/imunologia , Humanos , Células Tumorais Cultivadas
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