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1.
Curr Cancer Drug Targets ; 12(1): 23-43, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22111836

RESUMO

Angiogenesis is the formation of new blood vessels from the pre-existing vasculature. Besides its role in normal physiology, angiogenesis is significantly involved in many pathological conditions, including inflammation, cardiovascular diseases and cancer. Numerous studies have been undertaken in the area of tumor angiogenesis. It is known that pathological angiogenesis is necessary for tumors to proceed from avascular, dormant stage to vascular, sprouting stage and also contributes to their later invasion and metastasis. Playing a central role in tumor angiogenesis, vascular endothelial growth factor is considered as a key target in therapeutic approaches. This article aims to review the critical role of VEGF in tumor angiogenesis and the importance of VEGF-targeted strategies in cancer treatment.


Assuntos
Antineoplásicos/metabolismo , Neoplasias/metabolismo , Neoplasias/patologia , Neovascularização Patológica/metabolismo , Neovascularização Patológica/patologia , Fator A de Crescimento do Endotélio Vascular/fisiologia , Animais , Antineoplásicos/administração & dosagem , Sistemas de Liberação de Medicamentos/métodos , Sistemas de Liberação de Medicamentos/tendências , Humanos , Invasividade Neoplásica/patologia , Metástase Neoplásica/patologia , Neoplasias/tratamento farmacológico , Neovascularização Patológica/tratamento farmacológico , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/fisiologia
2.
Mini Rev Med Chem ; 12(1): 44-52, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22070692

RESUMO

Tetracyclines are an amazing class of chemical agents with multiple therapeutic potential. Structural modification of the original natural tetracyclines led to the synthesis and development of doxycycline and minocycline, compounds with higher lipophilicity, better oral pharmacokinetics and higher potency. Due to diverse pharmacological properties, these drugs are now under extensive investigation for use in the treatment of various disparate diseases. In recent years, several studies have conclusively reported anti-inflammatory, immune-modulating and neuroprotective effects of these compounds. There are currently over 200 ongoing clinical trials on tetracyclines. These studies extend over a wide range of diseases including dermatological diseases, behavior and mental disorders, immune system disorders, cardiovascular diseases, and cancer. In this review we will discuss the chemistry and pharmacology of these agents, and describe how their inhibitory effect on matrix metalloproteinase and on pro-inflammatory cytokines has kindled renewed interest in them. Based on the reports from pre-clinical and clinical trials, the therapeutic potential and application of tetracyclines may well be redefined and extensively extended.


Assuntos
Tetraciclinas/uso terapêutico , Anti-Inflamatórios , Ensaios Clínicos como Assunto , Humanos , Fatores Imunológicos , Fármacos Neuroprotetores , Tetraciclinas/farmacologia
3.
Korean J Radiol ; 8(3): 212-5, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17554188

RESUMO

OBJECTIVE: One of the best known side effects of using opium is spasm of the sphincter of Oddi, which may increase the diameter of the extrahepatic bile ducts. Ultrasound is the first imaging modality used for evaluating the biliary system because it is commonly available and noninvasive. The principal objective of this study was to measure the common bile duct (CBD) diameter via ultrasonography in opium addicts and to evaluate the relation between the CBD diameter and the period of addiction. MATERIALS AND METHODS: This research was an analytical-cross sectional study that was done on 110 opium addicts that were admitted to a drug treatment center. The diameter of the CBD in these cases was measured by ultrasonography and the results were analyzed with other factors like age, the period of addiction and the laboratory findings. RESULTS: According to the findings, there is a significant increase in the range of the CBD diameter in comparison with normal bile ducts. Also, the mean diameter of the CBD in the different age groups showed a significant difference (p < 0.0001) and there was a significant relation between the CBD diameter and the period of addiction (p < 0.001, r = 0.74); so, with the increased length of the addiction period, the mean CBD diameter increases. CONCLUSION: Opium addiction is one of the factors that causes extrahepatic bile duct dilatation, so in these cases, if no obstructing lesion was found on ultrasound examination and the serum bilirobine and alkaline phosphatase levels are normal, then further evaluation is not needed.


Assuntos
Doenças do Ducto Colédoco/diagnóstico por imagem , Ducto Colédoco/diagnóstico por imagem , Transtornos Relacionados ao Uso de Opioides/complicações , Adulto , Fatores Etários , Idoso , Doença Crônica , Estudos Transversais , Dilatação Patológica/diagnóstico por imagem , Humanos , Pessoa de Meia-Idade , Fatores de Tempo , Ultrassonografia
4.
J Steroid Biochem Mol Biol ; 89-90(1-5): 513-8, 2004 May.
Artigo em Inglês | MEDLINE | ID: mdl-15225830

RESUMO

1,25-Dihydroxyvitamin D(3) (1,25-(OH)(2) D(3)) is a potent regulator of cell growth and differentiation, with recent evidence showing inhibition of tumor invasion, angiogenesis and tumor cell death. The growth-inhibitory properties of 1,25-(OH)(2) D(3) could be harnessed in the treatment of patients with cancer if the development of systemic hypercalcemia is avoided. Hepatocellular cancer (HCC) presents a setting where the tumor is accessible for treatment through the hepatic artery and also where the tumor is highly lipiodol avid. On this basis, we hypothesised that, 1,25-(OH)(2) D(3) dissolved in lipiodol and administered through the hepatic artery may prove to be a rational approach to the use of the drug in the treatment of HCCs. In brief, 6 years of work with 1,25-(OH)(2) D(3) at cellular, animal and clinical level has provided us with plenty of support for this hypothesis. Sensitivity of HCCs in cell culture to 1,25-(OH)(2) D(3), growth retardation of human HCC xenografts in nude mice, uptake and retention of 1,25-(OH)(2) D(3)-lipiodol by liver tumors in cell culture and animals, escalation of the 1,25-(OH)(2) D(3) dose by 100x without the development of hypercalcemia in both liver tumor bearing rats and in patients with HCC are some of the evidence that will be discussed in this paper.


Assuntos
Calcitriol/uso terapêutico , Carcinoma Hepatocelular/tratamento farmacológico , Óleo Iodado/administração & dosagem , Neoplasias Hepáticas/tratamento farmacológico , Animais , Humanos , Camundongos , Camundongos Nus , Receptores de Calcitriol/fisiologia
5.
Int J Oncol ; 21(4): 901-6, 2002 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-12239633

RESUMO

1,25-dihydroxycholecalciferol [1,25-(OH)2 D3] has been shown to have antiproliferative effects in a wide variety of cancer cell lines. In vivo studies, although often limited by the development of hypercalcemia, have also shown the potential usefulness of 1,25-(OH)2 D3 in inhibiting tumor growth. The potential usefulness of the drug has been hampered by the development of hypercalcemia. This pilot clinical study was designed to evaluate the preclinical results that have shown, locoregional administration of 1,25-(OH)2 D3 in lipiodol can prevent the development of hypercalcemia. Eight patients with refractory HCC were given a single intrahepatic arterial dose (50, 75 or 100 microg) of 1,25-(OH)2 D3 dissolved in 5 ml of lipiodol. Following this, for 4 weeks serum calcium, 1,25-(OH)2 D3, alpha-fetoprotein and a range of biochemical indices were monitored. While, in 3 patients the calcium levels exceeded the normal range, even at these extremely high doses, non of the patients developed grade 3 hypercalcemia. 1,25-(OH)2 D3 administration also led to transient stabilization of serum alpha-fetoprotein in these patients. The data obtained support the hypothesis that, in patients with HCC, locoregional delivery of 1,25-(OH)2 D3 in lipiodol can allow administration of supra-pharmacological doses of the drug without the development of hypercalcemia.


Assuntos
Calcitriol/uso terapêutico , Carcinoma Hepatocelular/tratamento farmacológico , Óleo Iodado/farmacologia , Neoplasias Hepáticas/tratamento farmacológico , Idoso , Idoso de 80 Anos ou mais , Cálcio/metabolismo , Agonistas dos Canais de Cálcio/uso terapêutico , Divisão Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Feminino , Humanos , Injeções Intra-Arteriais , Masculino , Pessoa de Meia-Idade , Projetos Piloto , Fatores de Tempo , alfa-Fetoproteínas/metabolismo
6.
Indian J Med Res ; 116: 35-40, 2002 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-12514976

RESUMO

BACKGROUND & OBJECTIVES: The amygdala and hippocampus are recognized as the two important structures in the brain involved in the development and control of kindled seizures. The study on the precise interconnection between these two regions can provide important insights into the functional anatomy of complex partial seizures. In this study the effect of an experimentally increased excitability in hippocampal neurons, via hippocampal kindling, on the amygdala kindling rate was investigated in rats. METHODS: Animals were divided into four groups. Tripolar electrodes were implanted in the amygdala and CA1 region of the dorsal hippocampus of animals of Groups 1, 3 and 4. In Group 2 animals, tripolar electrodes were only implanted in the amygdala. In Group 1, one week after surgery, the rats were kindled first from the hippocampus and the next day kindled by amygdala stimulation. In Groups 2 and 3, one week after surgery, rats were kindled from the amygdala. Group 4 animals had a recovery period of one week plus 32 days, which was the mean of the hippocampal kindling rate in Group 1, and then were kindled from the amygdala. RESULTS: In Group 1, the amygdala kindling rate (n; number of days for which animals were stimulated before a stage 5 motor convulsion is triggered) and seizure stage at day n/2 were significantly facilitated and increased respectively. There was also a significant positive correlation between hippocampal and amygdala kindling rates. INTERPRETATION & CONCLUSION: Results obtained show that an increase in hippocampal excitability can facilitate kindling from the amygdala. Thus, it is suggested that the hippocampus has an important role in the development and propagation of seizures from the amygdala.


Assuntos
Tonsila do Cerebelo/fisiologia , Hipocampo/fisiologia , Excitação Neurológica/fisiologia , Animais , Estimulação Elétrica , Masculino , Ratos , Ratos Sprague-Dawley
7.
Cancer Chemother Pharmacol ; 48(3): 209-14, 2001 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-11592342

RESUMO

PURPOSE: We have previously shown that 1,25-dihydroxyvitamin D3 [1,25(OH)2D3] inhibits the proliferation of a number of human cancers, including colorectal and hepatocellular carcinoma, both of which affect the liver and are major causes of cancer death. However, the clinical use of 1,25(OH)2D3 and analogues has been restricted by the development of hypercalcaemia upon systemic administration. We hypothesized that a clinically significant hepatic first-pass effect may exist upon the administration of 1,25(OH)2D3 as a hepatic arterial infusion, and that such an effect may allow high levels of 1,25(OH)2D3 to be delivered to the liver whilst avoiding high systemic levels. METHODS: To examine this hypothesis, two groups of Landrace pigs were given identical doses of 1,25(OH)2D3 as continuous infusions, one group systemically, the other as a hepatic arterial infusion. Serum levels of 1,25(OH)2D3, calcium, phosphate and a number of liver and kidney function tests were performed regularly. RESULTS: Concentrations of 1,25(OH)2D3 and calcium remained normal in the hepatic arterial infusion animals, in contrast to the intravenous infusion animals which developed elevated levels of 1,25(OH)2D3 and hypercalcaemia. Hepatic arterial infusion of 1,25(OH)2D3 did not produce any adverse effects upon renal or hepatic function. CONCLUSION: The present findings support the existence of a clinically significant hepatic first-pass effect when 1,25(OH)2D3 is administered as a continuous hepatic arterial infusion. Hepatic arterial infusion of 1,25(OH)2D3 has great potential in the treatment of hepatic cancers.


Assuntos
Calcitriol/farmacocinética , Agonistas dos Canais de Cálcio/farmacocinética , Fígado/metabolismo , Alanina Transaminase/sangue , Animais , Área Sob a Curva , Aspartato Aminotransferases/sangue , Calcitriol/administração & dosagem , Cálcio/sangue , Agonistas dos Canais de Cálcio/administração & dosagem , Artéria Hepática , Infusões Intra-Arteriais , Infusões Intravenosas , Fosfatos/sangue , Suínos , Ureia/sangue
8.
Oncology ; 61(1): 42-6, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11474247

RESUMO

Our preclinical studies have shown that the widely used antiparasitic drug albendazole has potent antiproliferative activity against colorectal cancer (CRC) and hepatocellular carcinoma (HCC). This trial was designed to evaluate albendazole in a small number of patients (n = 7) with either HCC or CRC and hepatic metastases refractory to other forms of therapy. Albendazole was given at 10 mg/kg/day orally in two divided doses for a period of 28 days. To follow the effect of treatment, tumor markers, carcinoembryonic antigen (CEA) or alpha-feto protein (AFP), were measured routinely in these patients. A range of hematological and biochemical indices were also serially measured to monitor bone marrow, kidney or liver toxicity. Albendazole therapy resulted in a decrease in CEA in 2 patients. In the remaining 5 with measurable tumor markers, serum CEA or AFP was stabilized in 3 patients, while in the other 2, after an initial stabilization (5-10 days), the markers began to increase. In the 7 patients completing the trial, albendazole was well tolerated and there were no significant changes in any hematological, kidney or liver function tests, but 3 patients were withdrawn for severe neutropenia which was probably contributory to the death of 1 patient. These data support our previous experimental results demonstrating that albendazole has antitumor effects.


Assuntos
Albendazol/uso terapêutico , Antineoplásicos/uso terapêutico , Carcinoma Hepatocelular/tratamento farmacológico , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Hepáticas/tratamento farmacológico , Adulto , Idoso , Albendazol/administração & dosagem , Albendazol/efeitos adversos , Antineoplásicos/administração & dosagem , Antineoplásicos/efeitos adversos , Biomarcadores Tumorais/sangue , Contagem de Células Sanguíneas , Antígeno Carcinoembrionário/sangue , Carcinoma Hepatocelular/sangue , Carcinoma Hepatocelular/patologia , Neoplasias Colorretais/sangue , Neoplasias Colorretais/patologia , Esquema de Medicação , Feminino , Humanos , Neoplasias Hepáticas/sangue , Neoplasias Hepáticas/patologia , Masculino , Pessoa de Meia-Idade , Projetos Piloto , Resultado do Tratamento
9.
ANZ J Surg ; 71(7): 414-7, 2001 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-11450917

RESUMO

BACKGROUND: 1alpha,25-dihydroxyvitamin D3 (1,25[OH]2D3) has been shown to inhibit the proliferation of various cancer cells including colon, prostate, melanoma, osteosarcoma and breast cancer. METHODS: The human hepatoma cell line (HepG2) was cultured with 1,25(OH)2D3 or one of two analogues EB1089 or CB1093 for various durations. Cellular proliferation was measured by uptake of [3H]thymidine, and cell numbers were determined by trypan blue exclusion counting. RESULTS: 1,25(OH)2D3, EB1089 and CB1093 all inhibited proliferation of HepG2 by up to 90% after 5 days of treatment, compared to the untreated controls. Decreased proliferation was associated with an approximately 50% reduction in cell numbers at concentrations of up to 10(-10) mol/L after 5 days of treatment with 1,25(OH)2D3. Cell proliferation rapidly recovered in cultures treated with lower concentrations of 1,25(OH)2D3 (10(-10) and 10(-11) mol/L) when 1,25(OH)2D3 was removed from the cultures by placing cells in serum containing medium without 1,25(OH)2D3. When HepG2 cells were treated with 10(-8) mol/L 1,25(OH)2D3 for 5 weeks, there was still significant inhibition of proliferation, although at week 5 there was 66% inhibition compared to 93% at the end of week 1. CONCLUSIONS: 1,25(OH)2D3, EB1089 and CB1093 all significantly inhibit the proliferation of HepG2 hepatoblastoma cells, with EB1089 being the most potent at lower concentrations. Inhibition can be maintained for at least 4 weeks, but is reversed after removal of vitamin D3.


Assuntos
Antineoplásicos/farmacologia , Calcitriol/farmacologia , Hepatoblastoma/patologia , Neoplasias Hepáticas/patologia , Calcitriol/análogos & derivados , Divisão Celular/efeitos dos fármacos , Humanos , Células Tumorais Cultivadas
10.
Epilepsy Res ; 46(1): 45-51, 2001 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-11395288

RESUMO

In the female species, effect of estrogens on seizure activity is well documented, but not much is known on the effect of this ubiquitous steroid hormone on the seizure activity of the male species. In the present study, fully kindled male rats were treated with various doses (10, 30 and 50 microg/kg, i.p.) of estradiol benzoate (EB) daily, and kindled seizure parameters such as seizure stage (SS), after discharge duration (ADD) and stage 5 duration (S(5)D) were recorded at various times (0.25, 3 h and every 24 h for 96 h) after the first of daily EB treatments. While the 10-microg/kg dose of EB failed to produce any significant effect, the 30-microg/kg dose induced a triphasic effect on seizure parameters. An initially rapid increment of ADD (after 0.25 h), followed by significant decrease of all parameters at 48 h and later a significant increase in S(5)D was observed 96 h after the first of daily EB treatments. The 50-microg/kg dose of EB produced almost a similar but less marked pattern of effects. Pre-treatment with a 3-mg/kg dose of tamoxifen citrate (TAM), not only blocked the EB (30 microg/kg) effects till 72 h but also reduced the ADD and S(5)D significantly after 0.25 h, when compared to its control group. While pre-treatment with the 10-mg/kg dose of TAM only blocked the inhibitory effects of EB 48 h after the first of daily EB treatments. Administration of the latter dose of TAM alone induced a profile similar to EB treatment. These results may suggest that in male rats, estradiol treatment can both potentiate and attenuate kindled seizure parameters in a time dependent manner, and the stimulatory effects can not be blocked by TAM pre-treatment.


Assuntos
Tonsila do Cerebelo/fisiopatologia , Estradiol/farmacologia , Excitação Neurológica/efeitos dos fármacos , Convulsões/fisiopatologia , Tonsila do Cerebelo/efeitos dos fármacos , Tonsila do Cerebelo/fisiologia , Animais , Estimulação Elétrica , Estradiol/análogos & derivados , Excitação Neurológica/fisiologia , Masculino , Ratos , Ratos Sprague-Dawley , Tempo de Reação , Convulsões/etiologia , Tamoxifeno/farmacologia
11.
Cancer Lett ; 165(1): 43-9, 2001 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-11248417

RESUMO

Tubulin protein is a major target of drug molecules, and consequently, tubulin inhibitors have attracted great attention as antimitotic antitumor agents for chemotherapeutic use. It has been shown that, the benzimidazole carbamate group of antiparasitics including albendazole act by inhibiting tubulin polymerization. In this study, albendazole was tested in culture against a range of human, rat and mice hepatocellular carcinoma (HCC) cells and in vivo against human SKHEP-1 tumor growth in nude mice. Albendazole induced a dose-dependent inhibition of [(3)H]thymidine incorporation in all cell lines examined and a dramatic decline in cell numbers in SKHEP-1 cells. The inhibitory effect of albendazole was evident at the 100 nM concentration and at 1000 nM, proliferation in all cell lines examined was inhibited by more than 80%, while, proliferation of HepG2, Hep3B and SKHEP-1 were suppressed by more than 90%, compared to control. Cell cycle analysis revealed that, depending on the dose employed, albendazole can arrest SKHEP-1 cells at both G0-G1 (250 nM) and G2-M (1000 nM) phases of the cycle. Albendazole treatment (300 mg/kg per day oral for 20 days) of nude mice inoculated subcutaneously with SKHEP-1, led to profound suppression of tumor growth. Immunohistochemical analysis of these tumors revealed that compared to control, those treated with albendazole have lower growth fractions. These findings demonstrate that albendazole strongly suppresses both in vitro and in vivo proliferation of HCC cells.


Assuntos
Albendazol/uso terapêutico , Antineoplásicos/uso terapêutico , Carcinoma Hepatocelular/prevenção & controle , Neoplasias Hepáticas/prevenção & controle , Albendazol/farmacologia , Animais , Antineoplásicos/farmacologia , Carcinoma Hepatocelular/patologia , Contagem de Células , Ciclo Celular/efeitos dos fármacos , Divisão Celular/efeitos dos fármacos , DNA/biossíntese , DNA/efeitos dos fármacos , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Neoplasias Hepáticas/patologia , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Transplante de Neoplasias , Inibidores da Síntese de Ácido Nucleico/farmacologia , Inibidores da Síntese de Ácido Nucleico/uso terapêutico , Timidina/metabolismo , Transplante Heterólogo , Trítio
12.
Brain Res ; 891(1-2): 1-6, 2001 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-11164804

RESUMO

Using amygdaloid-kindling model of epilepsy, effects of acute estradiol treatment on seizure parameters were investigated in male rats. Fully kindled male rats were treated with various doses of estradiol benzoate (EB, 10, 30 and 50 microg/kg, i.p.) and kindling parameters such as seizure stage (SS), afterdischarge duration (ADD) and stage 5 duration (S5D) were elicited at various times (0.25, 1.5, 3 h and every 24 h for 96 h) post-drug administration. While the 10-microg/kg dose of EB failed to change seizure parameters, administration of the 30- and 50-microg/kg doses caused significant prolongation of ADD and S5D (was not changed significantly by the latter dose) at various time intervals post-drug administration. Pretreatment with the 3 mg/kg dose of tamoxifen citrate (TAM) inhibited the EB (30 microg/kg) effect, while pretreatment with the 10-mg/kg dose produced significant prolongation of ADD and S5D. These results suggest that in male amygdaloid kindled rats, acute estradiol treatment leads to an intensification of seizure that is manifested by increases in ADD and S5D. As the effect is evident 0.25 h post-EB administration and duel action of TAM in opposing the EB effect at low doses and potentiating it at the higher doses, the possibility of a genomic effect may be ruled out. The variable effects of TAM might be explained by its partial agonistic property on estrogen receptors


Assuntos
Tonsila do Cerebelo/efeitos dos fármacos , Epilepsia/metabolismo , Estradiol/metabolismo , Estradiol/farmacologia , Excitação Neurológica/efeitos dos fármacos , Ciclo Menstrual/metabolismo , Tonsila do Cerebelo/fisiopatologia , Animais , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Epilepsia/fisiopatologia , Estradiol/análogos & derivados , Antagonistas de Estrogênios/farmacologia , Feminino , Humanos , Excitação Neurológica/metabolismo , Masculino , Ratos , Ratos Sprague-Dawley , Fatores Sexuais , Tamoxifeno/farmacologia
13.
Anticancer Res ; 20(4): 2705-9, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-10953347

RESUMO

It is well established that 1, 25 dihydroxyvitamin D3 is capable of inhibiting the proliferation of a number of human cancer cell lines, including hepatoma cell lines. However, clinical usage in the treatment of cancers has been limited by its hypercalaemic effects. We hypothesised that by delivering 1, 25 dihydroxyvitamin D3 dissolved in a lipid based carrier agent as a hepatic arterial infusion it would be possible to achieve high local concentrations within hepatomas for prolonged periods, whilst avoiding high systemic concentrations and hypercalcaemia. We examined this hypothesis by administering a hepatic arterial infusion of 1, 25 dihydroxyvitamin D3 in either Lipiodol, Medium Chain Triglyceride (MCT), or saline to hepatoma bearing rats. Assay of serum and tissue concentrations revealed that this approach using lipiodol or triglyceride results in selective distribution of 1, 25-dihydroxyvitamin D3 into, and retention within hepatoma tissue and low initial systemic serum levels. Lipiodol was more effective in these respects than MCT. This method of administration has potential in the treatment of hepatoma.


Assuntos
Calcitriol/administração & dosagem , Óleo Iodado/administração & dosagem , Neoplasias Hepáticas Experimentais/tratamento farmacológico , Triglicerídeos/administração & dosagem , Animais , Calcitriol/farmacocinética , Portadores de Fármacos , Infusões Intra-Arteriais , Fígado/metabolismo , Masculino , Ratos , Ratos Sprague-Dawley , Células Tumorais Cultivadas
14.
Anticancer Res ; 20(4): 2739-44, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-10953352

RESUMO

BACKGROUND: 1,25-(OH)2 D3 has an in vitro growth regulator effect on different cancers. Unfortunately, dose-limiting toxicity (hypercalcemia) limits its use in anticancer therapy. For primary liver tumors, loco-regional delivery of 1,25-(OH)2 D3 in lipiodol might avoid high systemic concentrations and development of hypercalcemia. MATERIALS AND METHODS: 1,25-(OH)2 D3 alone or mixed in lipiodol, was delivered at different concentrations into the hepatic artery of rats bearing a primary liver tumor. Calcium levels, tumor volume and proliferation index were assessed after treatment. RESULTS: Serum calcium values were significantly lower when the drug was mixed into lipiodol. Treatment with 10 micrograms of 1,25-(OH)2 D3 in ethanol resulted in a decrease in proliferation index within the tumor. CONCLUSIONS: The delivery of 1,25-(OH)2 D3 mixed in lipiodol reduces the subsequent elevation of serum calcium. Locoregional treatment with 1,25-(OH)2 D3 was shown for the first time to be effective on primary liver tumor growth in vivo.


Assuntos
Calcitriol/administração & dosagem , Óleo Iodado/administração & dosagem , Neoplasias Hepáticas Experimentais/tratamento farmacológico , Animais , Cálcio/sangue , Divisão Celular/efeitos dos fármacos , Portadores de Fármacos , Injeções Intra-Arteriais , Masculino , Ratos , Ratos Sprague-Dawley , Células Tumorais Cultivadas
15.
Anticancer Res ; 20(2A): 723-7, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-10810346

RESUMO

The steroid hormone 1,25-dihydroxyvitamin D3 [1,25-(OH)2D3] has potential to be used as an anti-tumor agent, but its clinical application has been restricted by the strong systemic calcemic activity. Regional administration of the drug dissolved in lipiodol, might be a way of selectively delivering high concentrations of the drug to lipiodol avid tumor cells without causing systemic side effects. In acute (1 day treatment) and chronic (5 days treatment) experiments, efficacy of the drug dissolved in ethanol (control) or lipiodol and subsequently diluted in the culture medium was tested in vitro against the hepatoblastoma cell line HepG2. Using [3H]thymidine incorporation and cell count, antiproliferative effects of 1,25-(OH)2D3 dissolved in the two different solvents was compared. Microscopic examination of cells exposed to the lipiodol containing media revealed intra-cellular presence of the oil in abundance. Chronic treatment of cells with either formulation of 1,25-(OH)2D3 resulted in profound inhibition of cell proliferation. However, exposure of cells to 1,25-(OH)2D3 in lipiodol was followed by significantly greater and lasting inhibition of cell proliferation in both acute and chronic studies. These results indicate that, 1,25-(OH)2D3 dissolved in lipiodol probably acts as a sustained release drug depot formulation, in which case it could have some potential for the regional treatment of liver tumors.


Assuntos
Calcitriol/farmacocinética , Calcitriol/toxicidade , Divisão Celular/efeitos dos fármacos , Óleo Iodado , Antineoplásicos/farmacocinética , Antineoplásicos/toxicidade , Meios de Cultura , Hepatoblastoma/patologia , Humanos , Óleo Iodado/farmacologia , Cinética , Neoplasias Hepáticas/patologia , Soluções , Timidina/metabolismo , Células Tumorais Cultivadas
16.
Cancer Lett ; 151(1): 97-102, 2000 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-10766428

RESUMO

Inhibitory effects of 1,25-dihydroxyvitamin D3 (1,25-(OH)2D3) on the proliferation of a variety of cancer cell lines have been extensively reported. We have studied the effect of 1,25-(OH)2D3 (10(-11)-10(-6) M) on the proliferation of a number of human and rat liver cancer cell lines. Additionally, the effect of 1,25-(OH)2D3 (0.02-0.5 microg/kg per day) on the rate of growth of liver cancer cell line xenografts in nude mice was also investigated. In vitro, proliferation of Hep-3B, PLC/PRF/5, and SKHEP-1 cells was significantly inhibited by 1,25-(OH)2D3, while HTC and Novikoff cells were more resistant to the inhibitory effects of the drug. In vivo, treatment of SKHEP-1 tumor bearing nude mice with different doses of 1,25-(OH)2D3 significantly retarded tumor growth without the development of hypercalcemia.


Assuntos
Calcitriol/toxicidade , Calcitriol/uso terapêutico , Carcinoma Hepatocelular/patologia , Neoplasias Hepáticas/patologia , Animais , Antineoplásicos/uso terapêutico , Antineoplásicos/toxicidade , Carcinoma Hepatocelular/tratamento farmacológico , Divisão Celular/efeitos dos fármacos , DNA de Neoplasias/biossíntese , Humanos , Neoplasias Hepáticas/tratamento farmacológico , Camundongos , Camundongos Nus , Ratos , Timidina/metabolismo , Transplante Heterólogo , Células Tumorais Cultivadas
17.
Brain Res ; 858(1): 48-54, 2000 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-10700595

RESUMO

Effects of intraperitoneal and intraamygdala N(6)-cyclohexyladenosine (CHA), a selective adenosine A(1) receptor agonist, and 1,3-dimethyl-8-cyclopentylxanthine (CPT), a selective adenosine A(1) receptor antagonist, were examined in fully hippocampal kindled rats. Intraperitoneal administration of CHA (0. 25, 0.5 and 1 mg/kg) decreased hippocampal secondary afterdischarge duration (SAD) and amygdala afterdischarge duration (ADD). Only the 1 mg/kg dose induced a significant increase in latency to stage 4. Intraperitoneal administration of CPT (0.25, 0.5 and 1 mg/kg) induced a significant increase in stage 5 duration, hippocampal SAD and ADD. Pretreatment of animals with CPT (1 mg/kg), antagonized effects of CHA on seizure parameters. Intraamygdala microinfusion (1 microl over 2 min) of CHA (5 nM-1 mM) significantly reduced hippocampal SAD and amygdala ADD. These effects were antagonized by intraamygdala CPT (1 microM). Results obtained suggest that in hippocampal kindled rats, amygdala may be regarded as a relay point for AD propagation specially in recruit activity of the hippocampus.


Assuntos
Adenosina/análogos & derivados , Tonsila do Cerebelo/efeitos dos fármacos , Anticonvulsivantes/administração & dosagem , Hipocampo/efeitos dos fármacos , Excitação Neurológica/efeitos dos fármacos , Convulsões/prevenção & controle , Adenosina/administração & dosagem , Adenosina/antagonistas & inibidores , Tonsila do Cerebelo/fisiopatologia , Animais , Comportamento Animal/efeitos dos fármacos , Relação Dose-Resposta a Droga , Antagonismo de Drogas , Estimulação Elétrica , Hipocampo/fisiopatologia , Injeções Intraperitoneais , Masculino , Microinjeções , Agonistas do Receptor Purinérgico P1 , Antagonistas de Receptores Purinérgicos P1 , Ratos , Ratos Sprague-Dawley , Tempo de Reação/efeitos dos fármacos , Xantinas/administração & dosagem
18.
Anticancer Res ; 20(6B): 4257-60, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-11205255

RESUMO

BACKGROUND: Successful targeted delivery of 1,25-dihydroxyvitamin D3 [1,25-D3] for the treatment of liver cancer would necessitate the use of an appropriate delivery agent. MATERIALS AND METHODS: Using liver cancer cell line HepG2 in culture, we examined, the possibility of using medium-chain triglyceride (MCT) as a solvent for targeted delivery of 1,25-D3. The drug was made up in either the medium or first dissolved in MCT and subsequently diluted in the medium. Cells were exposed for 1 (acute) or 5 days (chronic) to the 2 different formulations of the drug and cell proliferation was measured by [3H]thymidine and cell count methods. RESULTS: In chronic experiments, exposure of cells to the MCT containing formulation of 1,25-D3 led to significantly greater inhibition of cell proliferation. In the acute experiments where, 1 day 1,25-D3 treatment was followed by 4 days of incubation with normal medium (no drug, no MCT), inhibition of proliferation was more than 2 fold greater in cells exposed to the 1,25-D3/MCT preparation. CONCLUSION: These results indicate that, 1,25-D3 dissolved in MCT probably accumulates and then acts as a sustained release drug depot formulation, in which case it may have potential for the regional treatment of liver tumors.


Assuntos
Calcitriol/administração & dosagem , Neoplasias Hepáticas/tratamento farmacológico , Triglicerídeos/administração & dosagem , Contagem de Células , Divisão Celular/efeitos dos fármacos , Química Farmacêutica , Relação Dose-Resposta a Droga , Combinação de Medicamentos , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/patologia , Timidina/metabolismo , Triglicerídeos/química , Células Tumorais Cultivadas/efeitos dos fármacos , Células Tumorais Cultivadas/metabolismo
19.
Epilepsy Res ; 37(1): 37-43, 1999 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-10515173

RESUMO

Possible anticonvulsant effects of 2-chloroadenosine injected focally into the perirhinal cortex of amygdala kindled rats were investigated over a 2 h period. Animals were microinfused (1 microl) with 2-chloroadenosine (2-CLA; 5, 10, 15, 25 and 100 nM) or artificial cerebrospinal fluid applied through a cannula located in the perirhinal cortex. At the doses employed, 2-CLA significantly reduced afterdischarge duration and stage 5 seizure duration. The latency to stage 4 seizure was increased only at the highest dose of 2-CLA (100 nM), while even at this dose no significant change in seizure stage could be seen. The maximum effect of 2-CLA was obtained 30 min after microinfusion of the drug. Pre-treatment (intraperirhinal cortex) of animals with the nonselective adenosine antagonist, caffeine (50 microM; 1 microl), blocked the anticonvulsant activity of 2-CLA. These results suggest that adenosine receptors located in the perirhinal cortex may play an important role in the suppression of seizure activity elicited from the amygdala.


Assuntos
2-Cloroadenosina/farmacologia , Tonsila do Cerebelo/fisiologia , Anticonvulsivantes/farmacologia , Excitação Neurológica , Condutos Olfatórios/fisiologia , 2-Cloroadenosina/antagonistas & inibidores , Adenosina/antagonistas & inibidores , Análise de Variância , Animais , Anticonvulsivantes/antagonistas & inibidores , Cafeína/farmacologia , Relação Dose-Resposta a Droga , Injeções , Masculino , Ratos , Ratos Sprague-Dawley , Tempo de Reação/efeitos dos fármacos , Convulsões/fisiopatologia , Convulsões/prevenção & controle
20.
J Ethnopharmacol ; 66(2): 211-5, 1999 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-10433480

RESUMO

This study investigates anticonvulsant effects of an essential oil of the fruits of Pimpinella anisum (Umbelliferae), a folkloric remedy in the Iranian traditional medicine, against seizures induced by pentylenetetrazole (PTZ) or maximal electroshock (MES) in male mice. The essential oil suppressed tonic convulsions induced by PTZ or MES. It also elevated the threshold of PTZ-induced clonic convulsions in mice. The essential oil produced motor impairment. However, this effect was not observed at the doses and time courses needed for anticonvulsant activity.


Assuntos
Anticonvulsivantes/farmacologia , Apiaceae/química , Óleos Voláteis/farmacologia , Animais , Convulsivantes , Eletrochoque , Etossuximida/farmacologia , Frutas/química , Índia , Irã (Geográfico) , Dose Letal Mediana , Masculino , Camundongos , Óleos Voláteis/toxicidade , Pentilenotetrazol/antagonistas & inibidores , Equilíbrio Postural/efeitos dos fármacos , Convulsões/induzido quimicamente , Convulsões/prevenção & controle , Turquia
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