Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 6 de 6
Filtrar
Mais filtros










Base de dados
Intervalo de ano de publicação
1.
Drug Alcohol Depend ; 188: 295-303, 2018 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-29807217

RESUMO

BACKGROUND: TV-1380 is a rationally mutated, human BChE fused to human serum albumin that has high hydrolytic enzymatic activity against cocaine and as well as an extended elimination half-life. OBJECTIVE: The present studies examined the safety of TV-1380 and its protective effect when given to monkeys alone or concomitantly with cocaine and ethanol. METHODS: A set of studies was conducted in monkeys with TV-1380. The parameters tested included telemetric assessment of cardiovascular parameters, clinical pathology, plasma analysis of cardiac troponin I, ex-vivo analyses of cocaethylene and PK analysis of serum concentrations of TV-1380, cocaine and its metabolites, and histopathological examinations. RESULTS: TV-1380 treatment in monkeys was well tolerated. TV-1380 pretreatment prior to cocaine significantly attenuated the cardiac effects of cocaine and reduced cocaine-induced elevations in serum cardiac troponin I. TV-1380 changed the metabolic fate of cocaine resulting in decreased exposure to benzoylecgonine, while increasing the exposure to ecgonine methyl ester in plasma.TV-1380 reduced the plasma levels of the toxic metabolite cocaethylene formed after co-administration of ethanol and cocaine. CONCLUSION: The results of this study demonstrate that TV-1380 not only accelerates the elimination of cocaine, but also protects the treated animal from the cardiac effects of cocaine, and inhibits the formation of the toxic cocaethylene metabolite when cocaine is given together with ethanol, supporting further clinical development of modified BChE products as possible treatments for cocaine abuse.


Assuntos
Albuminas/efeitos adversos , Albuminas/farmacologia , Albuminas/farmacocinética , Butirilcolinesterase/efeitos adversos , Butirilcolinesterase/farmacologia , Butirilcolinesterase/farmacocinética , Cocaína/análogos & derivados , Cocaína/antagonistas & inibidores , Etanol/antagonistas & inibidores , Proteínas Recombinantes de Fusão/efeitos adversos , Proteínas Recombinantes de Fusão/farmacologia , Proteínas Recombinantes de Fusão/farmacocinética , Animais , Butirilcolinesterase/sangue , Cocaína/sangue , Cocaína/metabolismo , Cocaína/farmacocinética , Cocaína/farmacologia , Interações Medicamentosas , Eletrocardiografia/efeitos dos fármacos , Etanol/sangue , Etanol/farmacocinética , Etanol/farmacologia , Feminino , Frequência Cardíaca/efeitos dos fármacos , Humanos , Macaca fascicularis , Masculino , Proteínas Recombinantes de Fusão/sangue , Respiração/efeitos dos fármacos , Troponina I/sangue
2.
Proc Natl Acad Sci U S A ; 113(41): E6145-E6152, 2016 10 11.
Artigo em Inglês | MEDLINE | ID: mdl-27671624

RESUMO

Laquinimod is an oral drug currently being evaluated for the treatment of relapsing, remitting, and primary progressive multiple sclerosis and Huntington's disease. Laquinimod exerts beneficial activities on both the peripheral immune system and the CNS with distinctive changes in CNS resident cell populations, especially astrocytes and microglia. Analysis of genome-wide expression data revealed activation of the aryl hydrocarbon receptor (AhR) pathway in laquinimod-treated mice. The AhR pathway modulates the differentiation and function of several cell populations, many of which play an important role in neuroinflammation. We therefore tested the consequences of AhR activation in myelin oligodendrocyte glycoprotein (MOG)-induced experimental autoimmune encephalomyelitis (EAE) using AhR knockout mice. We demonstrate that the pronounced effect of laquinimod on clinical score, CNS inflammation, and demyelination in EAE was abolished in AhR-/- mice. Furthermore, using bone marrow chimeras we show that deletion of AhR in the immune system fully abrogates, whereas deletion within the CNS partially abrogates the effect of laquinimod in EAE. These data strongly support the idea that AhR is necessary for the efficacy of laquinimod in EAE and that laquinimod may represent a first-in-class drug targeting AhR for the treatment of multiple sclerosis and other neurodegenerative diseases.


Assuntos
Encefalomielite Autoimune Experimental/etiologia , Encefalomielite Autoimune Experimental/metabolismo , Quinolonas/farmacologia , Receptores de Hidrocarboneto Arílico/agonistas , Receptores de Hidrocarboneto Arílico/metabolismo , Animais , Citocromo P-450 CYP1A1/genética , Citocromo P-450 CYP1A1/metabolismo , Encefalomielite Autoimune Experimental/tratamento farmacológico , Encefalomielite Autoimune Experimental/patologia , Feminino , Deleção de Genes , Expressão Gênica , Perfilação da Expressão Gênica , Regulação da Expressão Gênica/efeitos dos fármacos , Hepatócitos/metabolismo , Humanos , Sistema Imunitário/imunologia , Sistema Imunitário/metabolismo , Camundongos , Camundongos Knockout , Receptores de Hidrocarboneto Arílico/genética , Linfócitos T/imunologia , Linfócitos T/metabolismo , Transcriptoma
3.
Growth Horm IGF Res ; 30-31: 16-21, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27552669

RESUMO

PURPOSE: TV-1106 is a recombinant human albumin genetically fused to growth hormone which is intended to reduce the frequency of injections for GH therapy users. We report the safety, tolerability, pharmacokinetics and pharmacodynamics of repeated subcutaneous injections of TV-1106 in Cynomolgus monkeys. METHOD: Cynomolgus monkeys received four weekly subcutaneous injections of 0, 5, 10 or 20mg/kg TV-1106 and were monitored for safety signals throughout the study. Serum levels of TV-1106 and insulin-like growth factor 1 (IGF-1) were assayed. RESULTS: Treated animals showed no adverse effects or histopathological changes. TV-1106 serum concentrations showed sustained exposure to the drug. Exposure increased in a dose-dependent manner with peak concentrations at approximately 24h post-dosing and elimination half-lives in the range of 12 to 24h. IGF-1 serum concentrations were elevated throughout the entire study duration, indicative of the pharmacological response. There was a clear correlation between change in IGF-1 levels and dose or exposure to TV-1106. CONCLUSIONS: The safety, pharmacokinetic and pharmacodynamic findings support the further development of TV-1106 as a once-weekly administered treatment for patients with GHD.


Assuntos
Hormônio do Crescimento Humano/farmacologia , Fator de Crescimento Insulin-Like I/efeitos dos fármacos , Proteínas Recombinantes/farmacologia , Albumina Sérica Humana/farmacologia , Animais , Feminino , Hormônio do Crescimento Humano/efeitos adversos , Hormônio do Crescimento Humano/metabolismo , Humanos , Injeções Subcutâneas , Fator de Crescimento Insulin-Like I/metabolismo , Macaca fascicularis , Masculino , Proteínas Recombinantes/efeitos adversos , Proteínas Recombinantes/metabolismo , Albumina Sérica Humana/efeitos adversos , Albumina Sérica Humana/metabolismo
4.
Toxicol Pathol ; 40(1): 40-54, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22083585

RESUMO

Glatiramer acetate (GA), the active ingredient in Copaxone®, is a complex mixture of polypeptides used for the treatment of relapsing remitting multiple sclerosis. Glatiramoids are related mixtures that may differ in some characteristics of the prototype molecule. Our aim is to describe the long-term toxicity studies with protiramer (TV-5010), a new glatiramoid, in comparison with similar studies conducted with GA. The toxicity of twice-weekly subcutaneous injections of protiramer to Sprague-Dawley rats (twenty-six weeks) and cynomolgus monkeys (fifty-two weeks) was compared with similar studies done with daily subcutaneous injections of GA. Daily treatment with GA was safe and well tolerated, without systemic effects or death. Protiramer administration was not as well tolerated as GA and led to dose- and time-related mortalities, probably mediated through severe injection-site lesions both in rats and in monkeys. Bridging fibrosis in the liver and severe progressive nephropathy were seen in rats. A dose-related increase in eosinophils was observed in monkeys. The protiramer toxicity studies show that minor variations in the manufacturing of glatiramoids may lead to significant toxic effects. It is therefore essential that the safety of any new glatiramoid be studied in long-term preclinical studies before exposing humans.


Assuntos
Peptídeos/toxicidade , Análise de Variância , Animais , Análise Química do Sangue , Peso Corporal/efeitos dos fármacos , Avaliação Pré-Clínica de Medicamentos , Feminino , Acetato de Glatiramer , Imunossupressores/administração & dosagem , Imunossupressores/toxicidade , Injeções Subcutâneas , Nefropatias/induzido quimicamente , Nefropatias/patologia , Cirrose Hepática/induzido quimicamente , Cirrose Hepática/patologia , Macaca fascicularis , Masculino , Peptídeos/administração & dosagem , Ratos , Ratos Sprague-Dawley , Testes de Toxicidade Crônica
5.
Biores Open Access ; 1(2): 69-78, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23514783

RESUMO

Tissue-engineered bone grafts seeded with mesenchymal stem cells (MSCs) have been sought as a replacement for bone grafts currently used for bone repair. For production of osteogenic constructs, MSCs are isolated from bone marrow (BM) or other tissues, expanded in culture, then trypsinized, and seeded on a scaffold. Predifferentiation of seeded cells is often desired. We describe here bone progenitor cells (BPCs) obtained by direct osteogenic differentiation of unprocessed BM bypassing isolation of MSCs. Human BM aspirates were incubated for 2 weeks with a commonly used osteogenic medium (OM), except no fetal calf serum, serum substitutes, or growth factors were added, because responding stem and/or progenitor cells were present in the BM milieu. The adherent cells remaining after the culture medium and residual BM were washed out, expressed high levels of bone-specific alkaline phosphatase (ALP) on their surface, demonstrated high ALP activity, were capable of mineralization of the intercellular space, and expressed genes associated with osteogenesis. These parameters in BPCs were similar and even at higher levels compared to MSCs subjected to osteogenic differentiation for 2 weeks. The yield of BPCs per 1 mL BM was 0.71±0.39×10(6). In comparison, the yield of MSCs produced by adhesion of mononuclear cells derived from the same amount of BM and cultured in a commercial growth medium for 2 weeks was 0.3±0.17×10(6). When a scaffold was added to the BM-OM mixture, and the mixture was cultured in a simple rotational bioreactor; the resulting BPCs were obtained already seeded on the scaffold. BPCs seeded on scaffolds were capable of proliferation for at least 6 weeks, keeping high levels of ALP activity, expressing osteogenic genes, and mineralizing the scaffolds. Autologous rat BPCs seeded on various scaffolds were transplanted into critical-size calvarial defects. Six weeks after transplantation of polylactic acid/polyglycolic acid scaffolds, 76.1%±18.3% of the defects were filled with a new bone, compared to 37.9%±28.4% in the contralateral defects transplanted with the scaffolds without cells.

6.
Toxicol Pathol ; 37(3): 280-92, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19380839

RESUMO

Drug-induced nephrotoxicity is a major concern, since many pharmacological compounds are filtered through the kidneys for excretion into urine. To discover biochemical biomarkers useful for early identification of nephrotoxicity, metabolomic experiments were performed on Sprague-Dawley Crl:CD (SD) rats treated with the nephrotoxins gentamicin, cisplatin, or tobramycin. Using a combination of gas chromatography/mass spectrometry (GC/MS) and liquid chromatography/mass spectrometry (LC/MS), a global, nontargeted metabolomics analysis was performed on urine and kidney samples collected after one, five, and twenty-eight dosing days. Increases in polyamines and amino acids were observed in urine from drug-treated rats after a single dose, and prior to observable histological kidney damage and conventional clinical chemistry indications of nephrotoxicity. Thus, these metabolites are potential biomarkers for the early detection of drug-induced nephrotoxicity. Upon prolonged dosing, nephrotoxin-induced changes included a progressive loss of amino acids in urine, concomitant with a decrease in amino acids and nucleosides in kidney tissue. A nephrotoxicity prediction model, based on the levels of branched-chain amino acids in urine, distinguished nephrotoxin-treated samples from vehicle-control samples, with 100%, 93%, and 70% accuracy at day 28, day 5, and day 1, respectively. Thus, this panel of biomarkers may provide a noninvasive method to detect kidney injury long before the onset of histopathological kidney damage.


Assuntos
Rim/química , Metabolômica , Toxinas Biológicas/análise , Animais , Biomarcadores/análise , Biomarcadores/urina , Cromatografia Líquida/métodos , Cisplatino/análise , Diagnóstico Precoce , Feminino , Cromatografia Gasosa-Espectrometria de Massas/métodos , Gentamicinas/análise , Rim/patologia , Masculino , Espectrometria de Massas , Ratos , Ratos Sprague-Dawley , Fatores de Tempo , Tobramicina/análise
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...