RESUMO
CONTEXT: Bacterial sphingomyelinase (SMase) is thought to play a crucial role in bacterial evasion of the immune response during the early stages of infections. OBJECTIVE: The objective of this study was to predict the chemical structure required for competitive SMase inhibition, then synthesize and test the effect of potential inhibitors on the hydrolysis of sphingomyelin (SM) and protection against infection by Bacillus cereus. MATERIALS AND METHODS: We synthesized 10 potential SMase inhibitors, derivatives of RY221B-a analogues, based on predictions from three-dimensional structural analysis. We then tested the effect of these compounds on the inhibition of SM hydrolysis and protection of mice inoculated with B. cereus. RESULTS: One compound, SMY-540, displayed a strong inhibitory effect (IC50 = 0.8 µM) upon SMase and prevented mortality in mice. CONCLUSION: SMY-540 is an effective inhibitor of Bc-SMase and has potential for use in the development of drugs to treat infectious diseases caused by bacteria that produce SMase.
Assuntos
2,2'-Dipiridil/análogos & derivados , Bacillus cereus/efeitos dos fármacos , Proteínas de Bactérias/antagonistas & inibidores , Inibidores Enzimáticos/farmacologia , Infecções por Bactérias Gram-Positivas/tratamento farmacológico , Propanolaminas/farmacologia , Esfingomielina Fosfodiesterase/antagonistas & inibidores , 2,2'-Dipiridil/síntese química , 2,2'-Dipiridil/química , 2,2'-Dipiridil/farmacologia , Animais , Bacillus cereus/enzimologia , Bacillus cereus/patogenicidade , Bacillus subtilis/genética , Bacillus subtilis/metabolismo , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Inibidores Enzimáticos/síntese química , Inibidores Enzimáticos/química , Expressão Gênica , Infecções por Bactérias Gram-Positivas/microbiologia , Infecções por Bactérias Gram-Positivas/mortalidade , Hidrólise , Concentração Inibidora 50 , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos ICR , Simulação de Acoplamento Molecular , Propanolaminas/síntese química , Propanolaminas/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Esfingomielina Fosfodiesterase/genética , Esfingomielina Fosfodiesterase/metabolismo , Esfingomielinas/metabolismo , Esfingosina/análogos & derivados , Esfingosina/química , Relação Estrutura-Atividade , Análise de SobrevidaRESUMO
A novel sphingomyelin inhibitor RY221B-a, which contains a bipyridyl moiety as a metal coordination site was designed based upon the mechanism of phosphate ester hydrolysis. RY221B-a was synthesized from N-Boc-sphingosine in three steps via selective etherification using stannyl acetal. Synthesized RY221B-a exhibited relatively-strong inhibitory activity against Bc-SMase (IC(50)=1.2microM).
