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1.
Epilepsy Behav ; 105: 106950, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32092460

RESUMO

Epileptic spasms during infancy (infantile spasms, IS) are a rare epilepsy syndrome with dire prognosis. Current treatments, effective in about 55% of cases, include hormonal therapy (adrenocorticotropic hormone [ACTH] = adrenocorticotropin or corticosteroids) or vigabatrin (also in combination with hormones). In addition to their limited efficacy, these treatments may also carry serious adverse effects. Thus, the search for new effective drugs to treat this rare disease is desirable. In this study, we determined the efficacy of ACTON PROLONGATUM® (AP; Ferring Pharmaceuticals) in comparison with Acthar® Gel (Mallinckrodt) and full 39 amino-acid rat ACTH molecule (Genscript) in the rodent model of IS consisting of prenatal priming with betamethasone and repeated postnatal trigger of spasms with N-methyl-d-aspartate. Treatment with these ACTH varieties was given on postnatal days (P)12, P13, and P14 in a prospective test (treatment onset on P12 AFTER induction of spasms). Two independent arms were investigated: subcutaneous (SC) and intramuscular (IM) deliveries that were evaluated separately. In the SC arm, there was a significant suppression of the number of spasms after both Acthar® Gel and AP on P13 and P15 compared with gelatin control. In the IM arm, a significant suppression of the number of spasms was achieved only after AP on both P13 and P15 indicating that after IM delivery, Acthar® Gel was not as effective as AP. In this study, we confirmed the efficacy of two ACTH formulations (gelatin-based Acthar® Gel and carboxymethyl cellulose-based AP) in the model of IS. ACTON PROLONGATUM® may become a valuable therapy for IS. In our animal model, AP was at least as efficient as the standard of care, Acthar® Gel.


Assuntos
Hormônio Adrenocorticotrópico/uso terapêutico , Anticonvulsivantes/uso terapêutico , Modelos Animais de Doenças , Espasmos Infantis/tratamento farmacológico , Hormônio Adrenocorticotrópico/genética , Sequência de Aminoácidos , Animais , Animais Recém-Nascidos , Feminino , Géis , Humanos , Recém-Nascido , Gravidez , Estudos Prospectivos , Ratos , Espasmos Infantis/fisiopatologia , Vigabatrina/uso terapêutico
2.
Epilepsia ; 57(8): 1326-36, 2016 08.
Artigo em Inglês | MEDLINE | ID: mdl-27328917

RESUMO

OBJECTIVE: This study attempted to validate the effects of neonatal estradiol in ameliorating the spasms in the prenatally betamethasone-primed N-methyl-d-aspartate (NMDA) model of infantile spasms in rats as shown previously in a mouse Arx gene knock-in expansion model of infantile spasms. METHODS: Neonatal rats prenatally exposed to betamethasone (on day 15 of pregnancy) were treated with subcutaneous 40 ng/g estradiol benzoate (EB) between postnatal days (P)3-P10 or P0-P5. A synthetic estrogen analogue, diethylstilbestrol, was used between P0 and P5 (2 µg per rat, s.c.). On P12, P13, and P15, the rats were subjected to NMDA-triggered spasms, and latency to onset and number of spasms were evaluated. Rats with EB on P3-P10 were tested after spasms in the open field, novel object recognition, and elevated plus maze to determine effects of treatment on behavior. Additional rats with P3-P10 or P0-P5 EB were investigated for γ-aminobutyric acid (GABA)ergic neurons (glutamate decarboxylase [GAD]67 expression) in the neocortex. As a positive control, a group of rats received either subcutaneous adrenocorticotropic hormone (ACTH) (2 × 0.3 mg/kg on P12 and 3 × 0.3 mg/kg on P13 and P14) or vehicle after the first episode of spasms on P12. RESULTS: Neither EB treatment nor diethylstilbestrol consistently affected expression of spasms in this model, although we found a significant increase in GAD67-immunopositive cells in the neocortex after P3-P10 and P0-P5 EB treatment, consistent with a study in mice. Behavioral tests showed increase in lateralization in male rats treated with P3-P10 EB, a behavioral trait usually associated with female sex. Diethylstilbestrol treatment in male rats resulted in arrested pubertal descent of testes. ACTH had robust effects in suppressing spasms. SIGNIFICANCE: Treatment of infantile spasms (IS) using neonatal EB may be justified in those cases of IS that present with detectable deficits in GABAergic neurons. In other types of IS, the efficacy of neonatal EB and its analogues is not supported.


Assuntos
Anti-Inflamatórios/administração & dosagem , Betametasona/efeitos adversos , Estradiol/análogos & derivados , Efeitos Tardios da Exposição Pré-Natal/fisiopatologia , Espasmos Infantis/induzido quimicamente , Hormônio Adrenocorticotrópico/uso terapêutico , Fatores Etários , Animais , Animais Recém-Nascidos , Modelos Animais de Doenças , Estradiol/uso terapêutico , Comportamento Exploratório/fisiologia , Feminino , Glutamato Descarboxilase/metabolismo , Humanos , Lactente , Masculino , Aprendizagem em Labirinto/fisiologia , Neocórtex/metabolismo , Gravidez , Ratos , Ratos Sprague-Dawley , Reconhecimento Psicológico , Espasmos Infantis/tratamento farmacológico
3.
Emerg Infect Dis ; 19(11): 1803-10, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24188126

RESUMO

CTX-M extended-spectrum ß-lactamase (ESBL)-producing Klebsiella pneumoniae isolates are infrequently reported in the United States. In this study, we analyzed nonduplicate ESBL-producing K. pneumoniae and Escherichia coli clinical isolates collected during 2005-2012 at a tertiary care medical center in suburban New York City, USA, for the presence of blaCTX-M, blaSHV, blaTEM, and blaKPC genes. Despite a high prevalence of blaCTX-M genes in ESBL-producing E. coli since 2005, blaCTX-M genes were not detected in K. pneumoniae until 2009. The prevalence of CTX-M-producing K. pneumoniae increased significantly over time from 1.7% during 2005-2009 to 26.4% during 2010-2012 (p<0.0001). CTX-M-15 was the dominant CTX-M genotype. Pulsed-field gel electrophoresis and multilocus sequence typing revealed high genetic heterogeneities in CTX-M-producing K. pneumoniae isolates. This study demonstrates the recent emergence and polyclonal spread of multidrug resistant CTX-M-producing K. pneumoniae isolates among patients in a hospital setting in the United States.


Assuntos
Infecções por Klebsiella/epidemiologia , Klebsiella pneumoniae/metabolismo , População Suburbana , beta-Lactamases/biossíntese , Adulto , Idoso , Escherichia coli/classificação , Escherichia coli/genética , Escherichia coli/metabolismo , Feminino , Genótipo , Humanos , Infecções por Klebsiella/microbiologia , Klebsiella pneumoniae/classificação , Klebsiella pneumoniae/efeitos dos fármacos , Klebsiella pneumoniae/genética , Masculino , Testes de Sensibilidade Microbiana , Pessoa de Meia-Idade , Tipagem de Sequências Multilocus , Cidade de Nova Iorque/epidemiologia , Filogenia , Prevalência , beta-Lactamases/genética
4.
Neurosci Lett ; 813: 137431, 2023 09 14.
Artigo em Inglês | MEDLINE | ID: mdl-37591361

RESUMO

Epileptic spasms during infancy represent a devastating and refractory epilepsy syndrome. To advance studies on mechanisms and treatment using available mouse mutant models, we transferred our validated rat model of epileptic spasms to mice. Initially, we determined sensitivity of C57BL/6J mice to various doses (12-20 mg/kg) of NMDA on postnatal day 11 (P11) and P15. We primed mice with different doses of betamethasone (0.4-2.0 mg/kg) prenatally on gestational day (G)14 or G12 and tested spasms on P11. We also tested 2 different ACTH treatment paradigms (0.3 or 1.0 mg/kg) in prenatally primed as well as naïve mice. Data show that spasms in P11 mice, can be induced with the highest yield after 12 mg/kg dose of NMDA. Prenatal priming on G14 did not modify response to NMDA or sensitize spasms to ACTH. The betamethasone priming on G12 resulted in an increase in the number of NMDA-triggered spasms. Data indicate that the model transfer from rats to mice is non-linear and differences in prenatal brain development, metabolic rates, as well as sensitivity to convulsant drugs have to be considered.


Assuntos
N-Metilaspartato , Espasmos Infantis , Feminino , Gravidez , Ratos , Camundongos , Animais , Camundongos Endogâmicos C57BL , N-Metilaspartato/farmacologia , Espasmos Infantis/tratamento farmacológico , Betametasona/farmacologia , Modelos Animais de Doenças , Hormônio Adrenocorticotrópico
5.
Pharmacol Rep ; 75(1): 177-188, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36422805

RESUMO

BACKGROUND: Neurosteroids are investigated as effective antidotes for the poisoning induced by tetramethylenedisulfotetramine (TMDT) as well as treatments for epileptic spasms during infancy. Both these conditions are quite resistant to pharmacotherapy; thus, a search for new treatments is warranted. METHODS: In this study, we determined the efficacy of two novel neurosteroids, pregnanolone glutamate (PAG) and pregnanolone pyroglutamate (PPG), and tested these drugs in doses of 1-10 mg/kg (ip) against the TMDT syndrome and in our rodent model of infantile spasms. RESULTS: Only PPG in doses 5 and 10 mg/kg suppressed the severity of the TMDT syndrome and TMDT-induced lethality, while the 1 mg/kg dose was without an effect. Interestingly, the 1 mg/kg dose of PPG in combination with 1 mg/kg of diazepam was also effective against TMDT poisoning. Neither PAG nor PPG were effective against experimental spasms in the N-methyl-D-aspartate (NMDA)-triggered model of infantile spasms. CONCLUSIONS: While evidence suggests that PAG can act through multiple actions which include allosteric inhibition of NMDA-induced and glycine receptor-evoked currents as well as augmentation of É£-aminobutyric acid subtype A (GABAA) receptor-induced currents, the agent appears to neither have the appropriate mechanistic signature for activity in the infantile spasm model, nor the adequate potency, relative to PPG, for ameliorating the TMDT syndrome. The full mechanisms of action of PPG, which may become a potent TMDT antidote either alone or in combination with diazepam are yet unknown and thus require further investigation.


Assuntos
Neuroesteroides , Síndromes Neurotóxicas , Espasmos Infantis , Animais , Espasmos Infantis/induzido quimicamente , Espasmos Infantis/tratamento farmacológico , Pregnanolona/efeitos adversos , Ácido Pirrolidonocarboxílico , N-Metilaspartato/toxicidade , N-Metilaspartato/uso terapêutico , Roedores , Diazepam/farmacologia , Ácido Glutâmico , Espasmo
6.
Epilepsy Res ; 152: 31-34, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30875634

RESUMO

Epileptic spasms during infancy (infantile spasms) represent a serious treatment and social problem despite their rare occurrence. Current treatments include hormonal therapy (adrenocorticotropin-ACTH or corticosteroids) or vigabatrin (per se or in the combination). These treatments are partially effective and with potentially significant adverse effects. Thus, the search for new effective drugs is warranted. We tested efficacy of a novel fusion peptide AQB-565 developed by Aequus Biopharma in a model of infantile spasms consisting of prenatal exposure to betamethasone and repeated postnatal trigger of spasms with N-methyl-d-aspartic acid (NMDA). AQB-565 molecule includes the first 24 amino acids of ACTH, a ten amino acid linker and a modified melanocyte-stimulating hormone molecule. In contrast to ACTH with almost uniform activity over all peripheral and central melanocortin receptor isoforms, AQB is preferentially active on central melanocortin receptors MC3 and MC4. Here, we used equivalent doses of rat ACTH (full molecule) and AQB-565 and compared their efficacy in a prospective randomized test against of repeated bouts of spasms on postnatal days (P)12, P13 and P15 in the rat model. All doses of ACTH (range 0.02-1.0 mg/kg s.c.) and all doses but one of AQB-565 in the same range suppressed spasms in P15 rats (treatment stopped on P14). There was no dose-dependent effect and both compounds had all-or-none effect that is similar to clinical outcome of hormonal treatment of infantile spasms in children. Thus, AQB-565 may represent a novel treatment of infantile spasms similarly effective as ACTH but with potentially limited side effects.


Assuntos
Hormônio Adrenocorticotrópico/uso terapêutico , Hormônios Estimuladores de Melanócitos/uso terapêutico , Espasmos Infantis/tratamento farmacológico , Hormônio Adrenocorticotrópico/química , Hormônio Adrenocorticotrópico/metabolismo , Fatores Etários , Análise de Variância , Animais , Animais Recém-Nascidos , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Eletroencefalografia , Agonistas de Aminoácidos Excitatórios/toxicidade , Feminino , Humanos , Lactente , Masculino , Hormônios Estimuladores de Melanócitos/química , Hormônios Estimuladores de Melanócitos/metabolismo , N-Metilaspartato/toxicidade , Peptídeos/química , Peptídeos/metabolismo , Peptídeos/uso terapêutico , Gravidez , Efeitos Tardios da Exposição Pré-Natal/induzido quimicamente , Ratos , Ratos Sprague-Dawley , Espasmos Infantis/induzido quimicamente , Resultado do Tratamento
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