RESUMO
Tuberculosis remains the leading cause of death among infectious diseases, accounting for more than two million deaths annually. The incidence of the disease is increasing globally, partially because of the resurgence of drug-resistant strains of Mycobacterium tuberculosis. Calixarenes are macrocyclic oligomers, some of which are able to modify the growth of M. tuberculosis in infected cells. Most experimental work has been carried out with Macrocyclon, also known as HOC 12.5EO. In this study, we demonstrate that Macrocyclon is effective in controlling M. tuberculosis infections, and we provide evidence that its effect is partially mediated by an l-arginine-dependent mechanism of macrophage activation that involves the activity of the inducible nitric oxide synthase. We also show that Macrocyclon is effective in athymic and major histocompatibility complex class II-/- mice and synthesized a number of structurally related calixarenes expressing significant antimycobacterial activity.
Assuntos
Calixarenos/farmacologia , Ativação de Macrófagos , Mycobacterium tuberculosis/efeitos dos fármacos , Polietilenoglicóis/farmacologia , Tuberculose Pulmonar/prevenção & controle , Animais , Arginina/metabolismo , Células da Medula Óssea , Calixarenos/síntese química , Calixarenos/química , Calixarenos/uso terapêutico , Células Cultivadas , Feminino , Pulmão/microbiologia , Macrófagos/imunologia , Macrófagos/microbiologia , Macrófagos Peritoneais/microbiologia , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Camundongos Nus , Mycobacterium tuberculosis/isolamento & purificação , Óxido Nítrico Sintase/metabolismo , Óxido Nítrico Sintase Tipo II , Polietilenoglicóis/química , Polietilenoglicóis/uso terapêutico , Baço/microbiologia , Tuberculose Pulmonar/imunologia , Tuberculose Pulmonar/microbiologiaRESUMO
Methodologies to access water soluble large ringed calixarenes in good yield using efficient synthetic procedures have been investigated. Symmetrical partial functionalisations at the lower rim are described using activated [n]ethylene glycol chains and the addition behaviour contrasted with that of bromoalkanenitriles which proceeds with no observed regioselectivity. Full functionalisations of the calixarenes bearing hydrophilic groups are then investigated and a two-step procedure established which appears to be generally applicable for the addition of different [n]ethylene glycol chains. Furthermore, difunctionalisation under different reaction conditions are described. Throughout, strategies for the characterisation of these high mass compounds are outlined.
