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1.
J Microbiol Biotechnol ; 27(4): 668-677, 2017 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-28081359

RESUMO

Embryo implantation is the crucial step for a successful pregnancy. Diverse factors, including adhesion molecules, growth factors, and cytokines are important for embryo implantation through improving endometrial receptivity. Benzoic acid (BA), a component of various plants, has been shown to have antifungal and antioxidant effects. However, the effect of BA on embryo implantation remains unknown. Here, we showed the contribution of BA for the enhancement of endometrial receptivity through the leukemia inhibitory factor (LIF)-dependent increase of integrin αV, ß3, and ß5 expression. Furthermore, in vivo study using a mifepristone-induced implantation failure model showed that BA definitely improves the numbers of implantation embryos. Taken together, we suggest that BA has a novel function for embryo implantation through the up-regulation of LIF-mediated integrins, and may be a candidate for therapeutic medicine to increase the pregnancy rate.


Assuntos
Ácido Benzoico/farmacologia , Implantação do Embrião/efeitos dos fármacos , Integrina alfaVbeta3/metabolismo , Fator Inibidor de Leucemia/metabolismo , Receptores de Vitronectina/metabolismo , Animais , Adesão Celular/efeitos dos fármacos , Moléculas de Adesão Celular/efeitos dos fármacos , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Citocinas/metabolismo , Endométrio/efeitos dos fármacos , Receptor alfa de Estrogênio , Feminino , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Gravidez , Taxa de Gravidez , RNA Interferente Pequeno , Regulação para Cima
2.
Oncotarget ; 7(50): 83308-83318, 2016 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-27829217

RESUMO

Breast cancer is the most common malignant disease occurring in women and represents a substantial proportion of the global cancer burden. In these patients, metastasis but not the primary tumor is the main cause of breast cancer-related deaths. Here, we report the novel finding that DN10764 (AZD7762, a selective inhibitor of checkpoint kinases 1 and 2) can suppress breast cancer metastasis. In breast cancer cells, DN10764 inhibited cell proliferation and GAS6-mediated AXL signaling, consequently resulting in suppressed migration and invasion. In addition, DN10764 induced caspase 3/7-mediated apoptosis in breast cancer cells and inhibited tube formation of human umbilical vein endothelial cells. Finally, DN10764 significantly suppressed the tumor growth and metastasis of breast cancer cells in in vivo metastasis models. Taken together, these data suggest that therapeutic strategies targeting AXL in combination with systemic therapies could improve responses to anti-cancer therapies and reduce breast cancer recurrence and metastases.


Assuntos
Adenocarcinoma/tratamento farmacológico , Antineoplásicos/farmacologia , Neoplasias da Mama/tratamento farmacológico , Movimento Celular/efeitos dos fármacos , Neoplasias Pulmonares/prevenção & controle , Inibidores de Proteínas Quinases/farmacologia , Proteínas Proto-Oncogênicas/antagonistas & inibidores , Receptores Proteína Tirosina Quinases/antagonistas & inibidores , Transdução de Sinais/efeitos dos fármacos , Tiofenos/farmacologia , Ureia/análogos & derivados , Células A549 , Adenocarcinoma/genética , Adenocarcinoma/metabolismo , Adenocarcinoma/secundário , Animais , Apoptose/efeitos dos fármacos , Neoplasias da Mama/genética , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Caspase 3/metabolismo , Caspase 7/metabolismo , Proliferação de Células/efeitos dos fármacos , Relação Dose-Resposta a Droga , Feminino , Células Endoteliais da Veia Umbilical Humana/efeitos dos fármacos , Células Endoteliais da Veia Umbilical Humana/enzimologia , Células Endoteliais da Veia Umbilical Humana/patologia , Humanos , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/secundário , Camundongos Endogâmicos BALB C , Camundongos Nus , Neovascularização Fisiológica/efeitos dos fármacos , Proteínas Proto-Oncogênicas/genética , Proteínas Proto-Oncogênicas/metabolismo , Interferência de RNA , Receptores Proteína Tirosina Quinases/genética , Receptores Proteína Tirosina Quinases/metabolismo , Fatores de Tempo , Transfecção , Carga Tumoral/efeitos dos fármacos , Ureia/farmacologia , Ensaios Antitumorais Modelo de Xenoenxerto , Receptor Tirosina Quinase Axl
3.
Cell Transplant ; 24(5): 939-53, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-24593934

RESUMO

Duchenne muscular dystrophy (DMD) is an X-linked genetic disorder caused by mutations in the dystrophin gene. Adipose-derived stem cells (ASCs) are an attractive source of cells for stem cell therapy. Losartan has been reported to improve ASC transplantation in injured mouse muscles. In the present study, we investigated whether the combined treatment of losartan and ASCs in the injured muscles of mdx mice improves regeneration. The combined treatment of ASCs and losartan remarkably improved muscle regeneration and induced muscle hypertrophy. In addition, ASCs and losartan treatment downregulated transforming growth factor-ß and inhibited muscle fibrosis. We observed cells coexpressing green fluorescent protein (GFP) and dystrophin in the muscle samples of mice transplanted with GFP-positive ASCs. In the coculture in vitro experiment, we also observed that the GFP ASCs differentiated into dystrophin-expressing myotubes. The present study shows that the combination of transplanted ASCs and treatment with losartan ameliorated muscle fibrosis and improved muscle regeneration in injured mdx mice. Thus, we suggest that combined treatment with losartan and ASCs could help to improve muscle regeneration in the muscles of injured patients, including DMD patients.


Assuntos
Tecido Adiposo/metabolismo , Losartan/farmacologia , Músculo Esquelético/metabolismo , Distrofia Muscular de Duchenne/terapia , Transplante de Células-Tronco , Células-Tronco/metabolismo , Animais , Masculino , Camundongos , Camundongos Endogâmicos mdx , Camundongos Transgênicos , Músculo Esquelético/patologia , Distrofia Muscular de Duchenne/genética , Distrofia Muscular de Duchenne/metabolismo , Distrofia Muscular de Duchenne/patologia , Células-Tronco/patologia
4.
Inhal Toxicol ; 25(14): 794-801, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24304306

RESUMO

To define the relationship between the brain concentration of manganese and neurological signs, such as locomotion, after prolonged welding-fume exposure, cynomolgus monkeys were acclimated for 1 month and then divided into three concentration groups: unexposed, low concentration (31 mg/m(3) total suspended particulate (TSP), 0.9 mg/m(3) of Mn), and high concentration (62 mg/m(3) TSP, 1.95 mg/m(3) of Mn) of TSP. The monkeys were exposed to manual metal-arc stainless steel (MMA-SS) welding fumes for 2 h per day over 8 months in an inhalation chamber system equipped with an automatic fume generator. The home cage locomotor activity and patterns were determined using a camera system over 2-4 consecutive days. After 25 and 32 weeks of exposure, the home cage locomotor activity of the high-concentration primates was found to be 5-6 times higher than that of the unexposed primates, and this increased locomotor activity was maintained for 7 weeks after ceasing the welding-fume exposure, eventually subsiding to three times higher after 13 weeks of recovery. Therefore, the present results, along with our previous observations of a high magnetic resonance imaging (MRI) T1 signal in the globus pallidus and increased blood Mn concentration, indicate that prolonged welding-fume exposure can cause neurobehavioral changes in cynomolgus monkeys.


Assuntos
Poluentes Atmosféricos/toxicidade , Metais Pesados/toxicidade , Soldagem , Animais , Comportamento Animal/efeitos dos fármacos , Macaca fascicularis , Masculino , Atividade Motora/efeitos dos fármacos
5.
J Pharm Biomed Anal ; 56(3): 623-6, 2011 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-21757314

RESUMO

An assay method for the determination of oltipraz, a candidate drug for the treatment of liver fibrosis and liver cirrhosis, was developed in rat plasma using a fast-flow protein precipitation (FF-PPT) method coupled with LC-MS/MS for quantification to reduce the labor and to improve the speed of analysis. The applicability of the assay to pharmacokinetic studies was also evaluated. Oltipraz and ethyl-oltipraz, an internal standard (IS), were analyzed by multiple reaction monitoring (MRM) at m/z transitions of 227→193 and 241→174, respectively. A lower limit of quantification (LLOQ) of 20 ng/mL was observed, with a linear dynamic range from 20 to 4000 ng/mL (R>0.997). The accuracy, precision, dilution, recovery, and stability of the assay were deemed acceptable according to FDA guidelines. Oltipraz concentrations were measured successfully in plasma samples up to 12h post-dose in rats that had received an oral dose of 60 mg/kg. The findings indicate that the assay method is rapid and sensitive to oltipraz, showing applicability for pharmacokinetics (PK) studies of oltipraz in other small animals, including rats.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Pirazinas/sangue , Pirazinas/farmacocinética , Espectrometria de Massas em Tandem/métodos , Animais , Calibragem , Monitoramento de Medicamentos/métodos , Estabilidade de Medicamentos , Ratos , Padrões de Referência , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Tionas , Tiofenos
6.
Arch Toxicol ; 84(9): 719-29, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-20461361

RESUMO

3-Monochloropropane-1, 2-diol (or 3-chloro-1,2-propanediol, 3-MCPD) is a well-known food processing contaminant found in a wide range of foods and ingredients. It has been classified as non-genotoxic carcinogen but its carcinogenic potential in the rodents has been controversial. The carcinogenicity to B6C3F1 mice by drinking water administration was assessed over a period of 104 weeks. Three groups, each comprising 50 male and 50 female mice received 3-MCPD at dosages of 30, 100 or 300 ppm up to Day 100 and 200 ppm onward (4.2, 14.3 and 33.0 mg/kg for males; 3.7, 12.2, and 31.0 mg/kg for females), were allocated. Survival was good, with at least 80% of males and 72% of females in each group surviving 104 weeks. Body weights and body weight gain were decreased in males and females receiving 200 ppm. Water and food consumptions of both sexes at 300/200 ppm were lowered. Emaciated or crouching position was observed for animals of both sexes exposed to 200 ppm. There were some differences in hematology and serum biochemistry compared with controls, although there was no histopathological evidence to support those changes. Histopathological examination did not reveal any neoplastic or non-neoplastic findings attributable to treatment with 3-MCPD. It is concluded that drinking water administration of 3-MCPD for 104 weeks revealed no evidence of carcinogenic potential.


Assuntos
Testes de Carcinogenicidade , Carcinógenos/toxicidade , Glicerol/análogos & derivados , Administração Oral , Animais , Peso Corporal , Carcinógenos/administração & dosagem , Feminino , Contaminação de Alimentos , Glicerol/toxicidade , Masculino , Camundongos , Camundongos Endogâmicos , Distribuição Tecidual , alfa-Cloridrina
7.
Arch Toxicol ; 84(8): 609-18, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20221588

RESUMO

We investigated the effects of astemizole, a second-generation antihistamine, on the heart and peripheral blood mononuclear cells (PBMCs) and identified the early markers of its cardiotoxicity using gene expression profiling. Astemizole causes torsades de pointes, which is a type of ventricular tachycardia. We administered astemizole (dosage: 20, 60 mg/kg) to male Sprague-Dawley rats, using an oral gavage. Cardiac tissue and PBMCs were collected from the rats 4 h after treatment. Gene expression profiles were obtained using an Affymetrix GeneChip. The most deregulated genes were associated with energy metabolism pathways and calcium ion homeostasis in the heart of astemizole-treated rats. The most altered genes in the PBMCs were those involved in developmental processes and cardiotoxicity. Genes related to the response to oxidative stress, reactive oxygen species, heat shock proteins, hypoxia, immunity, and inflammation were also deregulated in the heart and PBMCs. These data provide further insight into the genetic pathways affected by astemizole. In addition, the simultaneously deregulated genes identified herein may be further studied. It will be interesting to find out whether single genes or certain sets of these genes could finally serve as biomarkers for cardiotoxicity of astemizole or other similar antihistamine drugs.


Assuntos
Astemizol/toxicidade , Expressão Gênica/efeitos dos fármacos , Coração/efeitos dos fármacos , Antagonistas não Sedativos dos Receptores H1 da Histamina/toxicidade , Leucócitos Mononucleares/efeitos dos fármacos , Animais , Perfilação da Expressão Gênica , Regulação da Expressão Gênica/efeitos dos fármacos , Leucócitos Mononucleares/metabolismo , Masculino , Miocárdio/metabolismo , Ratos , Ratos Sprague-Dawley
8.
Mol Pharm ; 7(3): 836-43, 2010 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-20349950

RESUMO

The need for an efficacious and safe oral anticoagulant that does not require monitoring has been largely unmet. Many efforts have centered on preparing orally available heparin to improve patient compliance. In this study, novel orally active heparin derivatives (LHD), i.e. low molecular weight heparin (LMWH) conjugated with deoxycholic acid (DOCA), were evaluated in vitro and in vivo for their enhancement effect of oral heparin absorption. After oral administration of 10 mg/kg of water-soluble LHD, Ws-LHD1.5 showed optimum oral efficacy and its bioavailability was about 24% in rats. The oral absorption of LHD1.5 was also enhanced by several solubilizers, among which Poloxamer 407 provided the best results. When 5 mg/kg of LHD1.5 with Poloxamer 407 was orally administered to monkeys, the maximum anti-FXa activity in plasma was 0.26 +/- 0.04 IU/mL and its bioavailability was 17.4%. In a rat thrombosis model, 5 mg/kg of orally administered LHD1.5 formulated with Poloxamer reduced thrombus formation by 63.9 +/- 16.6%, which was higher than the efficacy of clinically used enoxaparin (49.4 +/- 17.8% at 100 IU/kg, sc). Considering the oral absorption efficacy and therapeutic effect, the conjugation ratio was optimized as about 1.5 molecules of DOCA per mole of heparin. Therefore, LHD1.5 with Poloxamer 407 can be further formulated as a solid oral anticoagulant drug.


Assuntos
Anticoagulantes/administração & dosagem , Anticoagulantes/uso terapêutico , Heparina/administração & dosagem , Heparina/uso terapêutico , Administração Oral , Animais , Anticoagulantes/química , Ácido Desoxicólico/química , Heparina/química , Heparina de Baixo Peso Molecular/administração & dosagem , Heparina de Baixo Peso Molecular/química , Heparina de Baixo Peso Molecular/farmacologia , Masculino , Ratos , Ratos Sprague-Dawley , Trombose/tratamento farmacológico
9.
Int J Cardiol ; 145(2): 272-274, 2010 Nov 19.
Artigo em Inglês | MEDLINE | ID: mdl-19913309

RESUMO

KCNH-2 and KCNE-2 may encode the channel-forming alpha- and regulatory beta-subunits, respectively, of I(Kr) channels, which are involved in inherited or acquired long QT syndrome. However, in contrast to other multimeric channels, the stoichiometry of KCNH-2 and KCNE-2, which should be reasonably maintained if they are to be accepted as the components of a multi-molecular complex, has not been established, yet. In this study, we found that the protein expression of KCNE-2 was adequate to support the formation of a complex with KCNH-2; however, the level of transcription was not. This finding, together with previous data from electrophysiological and molecular biological studies, supports that KCNH-2 and KCNE-2 are molecular components of I(Kr) channels.


Assuntos
Canais de Potássio Éter-A-Go-Go/química , Canais de Potássio de Abertura Dependente da Tensão da Membrana/química , Animais , Canal de Potássio ERG1 , Canais de Potássio Éter-A-Go-Go/biossíntese , Canais de Potássio de Abertura Dependente da Tensão da Membrana/biossíntese , RNA Mensageiro/biossíntese , RNA Mensageiro/química , Ratos , Ratos Sprague-Dawley , Estereoisomerismo
10.
Arch Toxicol ; 84(3): 191-203, 2010 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19936710

RESUMO

Many in the welding industry suffer from bronchitis, lung function changes, metal fume fever, and diseases related to respiratory damage. These phenomena are associated with welding fumes; however, the mechanism behind these findings remains to be elucidated. In this study, the lungs of cynomolgus monkeys were exposed to MMA-SS welding fumes for 229 days and allowed to recover for 153 days. After the exposure and recovery period, gene expression profiles were investigated using the Affymetrix GeneChip Human U133 plus 2.0. In total, it was confirmed that 1,116 genes were up-or downregulated (over 2-fold changes, P\0.01) for the T1 (31.4 ± 2.8 mg/m3) and T2 (62.5 ± 2.7 mg/m3) dose groups. Differentially expressed genes in the exposure and recovery groups were analyzed, based on hierarchical clustering, and were imported into Ingenuity Pathways Analysis to analyze the biological and toxicological functions. Functional analysis identified genes involved in immunological disease in both groups. Additionally, differentially expressed genes in common between monkeys and rats following welding fume exposure were compared using microarray data, and the gene expression of selected genes was verified by real-time PCR. Genes such as CHI3L1, RARRES1, and CTSB were up-regulated and genes such as CYP26B1, ID4, and NRGN were down-regulated in both monkeys and rats following welding fume exposure. This is the first comprehensive gene expression profiling conducted for welding fume exposure in monkeys, and these expressed genes are expected to be useful in helping to understand transcriptional changes in monkey lungs after welding fume exposure.


Assuntos
Poluentes Ocupacionais do Ar/toxicidade , Expressão Gênica/efeitos dos fármacos , Pulmão/efeitos dos fármacos , Exposição Ocupacional/efeitos adversos , Aço/toxicidade , Soldagem , Animais , Perfilação da Expressão Gênica , Regulação da Expressão Gênica/efeitos dos fármacos , Exposição por Inalação , Pulmão/imunologia , Pulmão/patologia , Macaca fascicularis , Masculino , Análise de Sequência com Séries de Oligonucleotídeos , RNA Mensageiro/metabolismo
11.
Toxicol Res ; 26(4): 275-83, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24278535

RESUMO

Placenta transfer study in non-human primate (NHP) is one of the crucial components in the assessment of developmental toxicity because of the similarity between NHP and humans. To establish the method to determine placenta transfer in non-human primate, toxicokinetics of valproic acid (VPA) , a drug used to treat epilepsy in pregnant women, were determined in pregnant cynomolgus monkeys. After mating, pregnancy-proven females were daily administered with VPA at dose levels of 0, 20, 60 and 180 mg/kg by oral route during the organogenesis period from gestation day (GD) 20 to 50. Concentrations of VPA and its metabolite, 4-ene-VPA, in maternal plasma on GDs 20 and 50, and concentrations of VPA and 4-ene-VPA in placenta, amniotic fluid and fetus on GD 50 were analyzed using LC/MS/MS. Following single oral administration of VPA to pregnant monkeys, concentrations of VPA and 4-ene-VPA were generally quantifiable in the plasma from all treatment groups up to 4-24 hours post-dose, demonstrating that VPA was absorbed and the monkeys were systemically exposed to VPA and 4-ene-VPA. After repeated administration of VPA to the monkeys, VPA was detected in amniotic fluid, placenta and fetus from all treatment groups, demonstrating that VPA was transferred via placenta and the fetus was exposed to VPA, and the exposures were increased with increasing dose. Concentrations of 4-ene-VPA in amniotic fluid and fetus were below the limit of quantification, but small amount of 4-ene-VPA was detected in placenta. In conclusion,pregnant monkeys were exposed to VPA and 4-ene-VPA after oral administration of VPA at dose levels of 20, 60 and 180 mg/kg during the organogenesis period. VPA was transferred via placenta and the fetus was exposed to VPA with dose-dependent exposure. The metabolite, 4-ene VPA, was not detected in both amniotic fluid and fetus, but small amount of 4-ene-VPA was detected in placenta. These results demonstrated that proper procedures to investigate placenta transfer in NHP, such as mating and diagnosis of pregnancy via examining gestational sac with ultrasonography, collection of amniotic fluid, placenta and fetus after Caesarean section followed by adequate bioanalysis and toxicokinetic analysis, were established in this study using cynomolugus monkeys.

12.
Arch Environ Contam Toxicol ; 58(1): 222-9, 2010 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19466477

RESUMO

Arsenic (As) is a known human carcinogen and widely distributed in the environment. The main route of As exposure in the general population is through food and drinking water. Seafood harvested in Korea contains high-level organoarsenics such as arsenobetaine, arsenocholine, and arsenosugars, which are much less harmful than inorganic arsenics. However, for those who eat large amounts of seafood it is important to understand whether seafood consumption affects urinary levels of inorganic As metabolites such as arsenite, arsenate, monomethylarsonic acid (MMA), and dimethylarsinic acid (DMA). In this study we investigated urinary As metabolites (inorganic As, MMA[V], DMA[V]) and some biological indexes such as AST, GSH, GPX, lipid peroxidation, and uric acid in volunteer study subjects (seven males and nine females). Total urinary As metabolites were analyzed by the hydride generation method, followed by arsenic speciation using HPLC with ICP-mass spectrometry. Study subjects refrained from eating seafood for 3 days prior to the first urine collection and then ingested seafood daily for 6 consecutive days. The first voided urine of the morning was collected from each subject the first day of the consecutive 6 days of seafood ingestion but prior to the first seafood meal. The first voided urine of the morning was also collected on days 1, 2, 3, 4, 5, 6, 7, 10, and 14 after seafood ingestion. The daily mean intake of total As was 6.98 mg, comprised of 4.71 mg of seaweed (67%), 1.74 mg of flat fish (25%), and 0.53 mg of conch (8%). We observed a substantial increase in total urinary As metabolites for subjects consuming seafood from day 1, which recovered to control level at day 10. The increase in total urinary As metabolites was attributed to the increase in DMA, which is a more harmful metabolite than organoarsenics. However, no significant changes in response biological indexes were observed. These results suggest that it is necessary to evaluate As metabolism when assessing the exposure to inorganic As and potential chronic health effects of seafood consumption in Korea.


Assuntos
Arsênio/urina , Contaminação de Alimentos , Alimentos Marinhos/análise , Arsênio/administração & dosagem , Arsênio/análise , Arsenicais/urina , Ácido Cacodílico/urina , Cromatografia Líquida de Alta Pressão , Monitoramento Ambiental , Comportamento Alimentar , Feminino , Humanos , Masculino
13.
J Pharm Biomed Anal ; 50(5): 872-7, 2009 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-19577404

RESUMO

CKD-501 (i.e., lobeglitazone), a potent agonist for both PPARalpha/gamma, is a new drug that has potential clinical applications in the management of type-2 diabetes. The objective of this study was to develop a rapid and sensitive method for the determination of CKD-501 in rat plasma and to assess the applicability of the assay to pharmacokinetic studies. Rat plasma samples were processed using a fast flow protein precipitation (FF-PPT) method and then introduced onto an LC-MS/MS system for quantification. The analyte and rosiglitazone, an internal standard, were analyzed by multiple reactions monitoring (MRM) at m/z transitions of 482.0-->258.0 for CKD-501 and 358.0-->135.0 for the internal standard. The lower limit of quantification (LLOQ) was determined at 50 ng/mL, with an acceptable linearity in the range from 50 to 10,000 ng/mL (R>0.999). Validation parameters such as accuracy, precision, dilution, recovery, matrix effect and stability were found to be within the acceptance criteria of the assay validation guidelines, indicating that the assay is applicable to estimating the concentration in the range studied. The concentration of CKD-501 was readily quantifiable in plasma samples up to 24 h post-dose in rats that had received an oral dose of 1 mg/kg. These observations suggest, therefore, that the validated assay can be used in pharmacokinetic studies of CKD-501 in small animals such as the rat.


Assuntos
Cromatografia Líquida/métodos , Pirimidinas/análise , Espectrometria de Massas em Tandem/métodos , Tiazolidinedionas/análise , Administração Oral , Animais , Calibragem , Química Farmacêutica/métodos , Relação Dose-Resposta a Droga , Estabilidade de Medicamentos , Feminino , PPAR alfa/agonistas , Pirimidinas/farmacocinética , Controle de Qualidade , Ratos , Ratos Sprague-Dawley , Padrões de Referência , Reprodutibilidade dos Testes , Rosiglitazona , Tiazolidinedionas/farmacocinética , Tiazolidinedionas/farmacologia
14.
Artigo em Inglês | MEDLINE | ID: mdl-18945647

RESUMO

A reverse-phase high performance liquid chromatography method with electrospray ionization and detection by mass spectrometry is described for the simultaneous determination of doxifluridine and its active metabolite 5-fluorouracil in monkey serum. A liquid/liquid extraction with ethyl acetate (90%) and isopropyl alcohol (10%) was used to extract simultaneously doxifluridine and 5-FU which have considerable difference in the polarity. Optimum chromatographic separation was achieved on a Agilent Zorbax C(18) (100 mm x 2.1mm, 3.5 microm) column with a mobile phase of methanol-water (20:80, v/v). The flow rate was 0.2 mL/min with total cycle time of 5 min. The lower limit of quantification (LLOQ) was validated at 10.0 ng/mL of serum for both doxifluridine and 5-FU. Accuracy and precision of quality control (QC) samples for both compounds met FDA Guidance criteria of +/-15% with average QC accuracy of 95.5-105.0% and coefficients of variation of 1.1-9.5% in the 10-2000 ng/mL concentration range. This method demonstrated adequate sensitivity, specificity, accuracy, precision, stability to support the analysis of monkey serum samples.


Assuntos
Antimetabólitos Antineoplásicos/sangue , Cromatografia Líquida de Alta Pressão/métodos , Floxuridina/sangue , Fluoruracila/sangue , Espectrometria de Massas em Tandem/métodos , Administração Oral , Animais , Antimetabólitos Antineoplásicos/farmacocinética , Estabilidade de Medicamentos , Floxuridina/farmacocinética , Modelos Lineares , Macaca fascicularis , Masculino , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Espectrometria de Massas por Ionização por Electrospray/métodos
15.
Inhal Toxicol ; 20(12): 1075-83, 2008 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-18728992

RESUMO

The shortening of the MRI T1 relaxation time, indicative of a high signal intensity in a T1-weighted MRI, is known as a useful biomarker for Mn exposure after short-term welding-fume exposure. A previous monkey experimental study found that the T1 relaxation times decreased time-dependently after exposure, and a visually detectable high signal intensity appeared after 150 days of exposure. The nadir for the shortening of the T1 relaxation time was also previously found to correspond well with the blood Mn concentration in welders, suggesting a correlation between a prolonged high blood Mn concentration and shortened T1 relaxation time. Accordingly, to clarify the clearance of the brain Mn concentration after the cessation of welding-fume exposure, cynomolgus monkeys were assigned to 3 groups-unexposed, low dose (31 mg/m(3) total suspended particulate (TSP), 0.9 mg Mn/m(3)), and high dose (62 mg/m(3) TSP, 1.95 mg Mn/m(3))-and exposed to manual metal-arc stainless steel (MMA-SS) welding fumes for 2 h per day for 8 mo in an inhalation chamber system equipped with an automatic fume generator. After reaching the peak MRI T1 signal intensity (shortest T1 relaxation time), the monkeys were allowed to recover by ceasing the welding-fume exposure. Within 2 mo, the MRI T1 signal intensities for the exposed monkeys returned to nearly the same level as those for the unexposed monkeys, indicating the potential for recovery from a high MRI T1 signal intensity induced by welding-fume exposure, even after prolonged exposure. Clearance of the Mn tissue concentration was also demonstrated in the globus pallidus, plus other tissues from the brain, liver, spleen, and blood. In contrast, there was no clearance of the lung concentrations of Mn, indicating that a soluble form of Mn was transported to the blood and brain. Therefore, the solubility of Mn in welding fumes would appear to be an important determinant as regards the retention of blood Mn levels and brain tissue Mn concentrations in welders.


Assuntos
Poluentes Ocupacionais do Ar/toxicidade , Encéfalo/metabolismo , Exposição por Inalação/efeitos adversos , Imageamento por Ressonância Magnética/métodos , Soldagem/métodos , Poluentes Ocupacionais do Ar/sangue , Animais , Encéfalo/efeitos dos fármacos , Macaca fascicularis , Masculino , Manganês/sangue , Manganês/toxicidade , Fatores de Tempo
16.
Toxicol Res ; 24(2): 119-127, 2008 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32038786

RESUMO

The objectives of this study were to examine the lung injury and inflammation caused by manual metal arc stainless steel (MMA-SS) welding fume inhalation and to evaluate the recovery process. Sprague-Dawley rats were exposed to MMA-SS welding fumes for 2 h per day in a whole-body exposure chamber, with a total suspended particulate (TSP) concentration of 51.4 ± 2.8 mg/m3 (low dose) or 84.6 ± 2.9 mg/m3 (high dose) for 30 days. The animals were sacrificed after 30 days of exposure as well as after a 30-day recovery period. To assess the inflammatory or injury responses, cellular and biochemical parameters as well as cytokines were assayed in the bronchoalveolar lavage fluid (BALF). MMA-SS welding fume exposure led to a significant elevation in the number of alveolar macrophages (AM) and polymorphonuclear cells (PMN). Additionary, the values of ß-nacetyl glucosaminidase (ß-NAG) and lactate dehydrogenase (LDH) in the BALF were increased in the exposed group when compared to controls. After 30 days of recovery from exposure, a significant reduction in inflammatory parameters of BALF was observed between the exposed and recovered groups. Slight, but significant elevations were noted in the number of AM and PMN in the recovered groups, and AM that had been ingested fume particles still remain in the lungs. In conclusion, these results indicated that welding fumes induced inflammatory responses and cytotoxicity in the lungs of exposed rats. Fume particles were not fully cleared from lungs even after a 30-day recovery period.

17.
Toxicol Res ; 24(3): 219-225, 2008 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32038799

RESUMO

A screening study of the acute toxicity of organic arsenics such as arsenobetaine and arsenocholine, a product of arsenic methylation metabolite, and inorganic arsenic was carried out to examine hematological and serum biochemical parameters in cynomolgus monkeys (Macaca fascicularis). We found soft and liquid feces, and vomiting in all treated groups with inorganic and organic arsenics. The monkeys in inorganic arsenic-treated group showed a significant increase in vomiting frequency compared with those in three organic arsenics-treated groups. These results suggest that inorganic arsenic might be more toxic than three other organic arsenics tested. The monkeys in inorganic arsenic-treated group showed a decrease in platelet and an increase in monocyte on day 4 and the monkeys in arsenocholine-treated group showed an increase in reticulocyte percentage on day 8. The monkeys in inorganic-treated group also showed decreases in AST and ALT values and the monkeys in arsenobetaine-treated group showed a decrease in AST value and an increase in T-CHO value. However, these hematological and biochemical changes were within the physiological ranges, showing that the single dose of inorganic and organic arsenics did not affect at least hematological and serum biochemical parameters. The present study of toxicity with single dose of arsenics provides valuable indicators for longer term study of toxicity of repeated doses of arsenics in primates.

18.
Toxicol Res ; 24(4): 289-295, 2008 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32038807

RESUMO

Toxicology screening following treatment with astemizole, a histamine receptor antagonist, at oral doses of 0, 10, 30 and 60 mg/kg was carried out in male cynomolgus monkeys (Macaca fascicularis). No dose-related changes in mortality, clinical signs, body weight changes, food consumption, or urine analysis occurred in any animal compared to the vehicle control. However, the high-dose group showed a decrease in BUN and ALP compared to vehicle control group. In addition, the levels of TG, AST, ALP and CK increased. Although astemizole did not produce significant toxicological changes at any dose tested, we predict that it can cause toxicological changes of the liver and heart based on the changes in the serum parameters related to the heart and liver. The Action Potential Duration (APD) was prolonged in the heart of 60 mg/kg treatment group compared to the control group. The APD increase in 60 mg/kg treatment group along the other related changes in toxicological parameters imply that astemizole has major cardiotoxic effects in the cynomolgus monkey. This study is a valuable assessment for predicting the general toxicity and cardiotoxic effects of antihistamine drugs using nonhuman primates.

19.
J Toxicol Sci ; 32(4): 411-20, 2007 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-17965555

RESUMO

Toxicity screening of a newly developed oral heparin derivative was carried out in twelve male cynomolgus monkeys (Macaca fascicularis), composed of three treatment and vehicle control groups. A newly orally active heparin derivative, developed by Seoul National University, was given to the treatment group at three doses with low (12.8 mg/kg), medium (89.6 mg/kg) and high (640 mg/kg) doses for 14 days. A treatment group did not show any change in body weights, hematological parameters (e.g., RBC, WBC, platelet, PDW, MPV, etc.) and serum biochemical parameters (e.g., AST, ALT, BUN, etc.) for 2 weeks compared with those of the vehicle control group. These findings indicated that the oral anticoagulant drug, a newly developed oral heparin derivative, did not have any toxic effect for 2 week in this study. The present study will be valuable in the proper interpretation for non-clinical study using cynomolgus monkeys in the development of a new drug of heparin derivative.


Assuntos
Anticoagulantes/toxicidade , Ácido Desoxicólico/análogos & derivados , Heparina de Baixo Peso Molecular/análogos & derivados , Testes de Toxicidade , Administração Oral , Animais , Anticoagulantes/química , Ácido Desoxicólico/química , Ácido Desoxicólico/toxicidade , Esquema de Medicação , Heparina de Baixo Peso Molecular/química , Heparina de Baixo Peso Molecular/toxicidade , Macaca fascicularis , Masculino , Estrutura Molecular
20.
J Control Release ; 123(2): 155-63, 2007 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-17884230

RESUMO

The development of orally active heparin will have tremendous clinical importance since it can be used to effectively prevent deep vein thrombosis (DVT) in a long-term chronic treatment. We developed in this study a new orally active heparin derivative (Db-LHD), which has heparin chemically conjugated with deoxycholic acid and DMSO molecules by secondary interactions. Db-LHD was prepared in the powder form in soft capsules. When we administered Db-LHD capsules to monkeys, its oral physiological availability was increased up to 16.6%. The maximum anti-FXa activity at 5 mg/kg of Db-LHD was more than twice the minimum effective anti-FXa activity (MEC, 0.1 IU/mL) for preventing DVT, and the anti-FXa activity in plasma was maintained for 10 h above the MEC in monkeys. Also, we evaluated anti-thrombogenic effect of Db-LHD in a rat thrombosis model. A subcutaneous administration of enoxaparin (100 IU/kg), which was the highest recommended dose for the prevention of venous thromboembolism, reduced thrombus formation by 38.9+/-14.2%. On the other hand, 5 mg/kg (425 IU/kg) of orally administered Db-LHD reduced thrombus formation by 51.0+/-2.0. We propose a new orally active heparin, Db-LHD, in a solid dosage form to effectively prevent DVT and PE.


Assuntos
Anticoagulantes/farmacologia , Ácido Desoxicólico/análogos & derivados , Heparina de Baixo Peso Molecular/análogos & derivados , Trombose Venosa/prevenção & controle , Administração Oral , Animais , Anticoagulantes/administração & dosagem , Anticoagulantes/química , Anticoagulantes/farmacocinética , Anticoagulantes/toxicidade , Cápsulas , Química Farmacêutica , Ácido Desoxicólico/administração & dosagem , Ácido Desoxicólico/química , Ácido Desoxicólico/farmacocinética , Ácido Desoxicólico/farmacologia , Ácido Desoxicólico/toxicidade , Dimetil Sulfóxido/química , Modelos Animais de Doenças , Composição de Medicamentos , Enoxaparina/farmacologia , Inibidores do Fator Xa , Heparina de Baixo Peso Molecular/administração & dosagem , Heparina de Baixo Peso Molecular/química , Heparina de Baixo Peso Molecular/farmacocinética , Heparina de Baixo Peso Molecular/farmacologia , Heparina de Baixo Peso Molecular/toxicidade , Absorção Intestinal , Ligadura , Macaca fascicularis , Masculino , Camundongos , Camundongos Endogâmicos ICR , Pós , Ratos , Ratos Sprague-Dawley , Solventes/química , Veia Cava Inferior/cirurgia
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