RESUMO
Sixteen disulfides derived from disulfiram (Antabuse™) were evaluated as antibacterial agents. Derivatives with hydrocarbon chains of seven and eight carbons in length exhibited antibacterial activity against Gram-positive Staphylococcus, Streptococcus, Enterococcus, Bacillus, and Listeria spp. A comparison of the cytotoxicity and microsomal stability with disulfiram further revealed that the eight carbon chain analog was of lower toxicity to human hepatocytes and has a longer metabolic half-life. In the final analysis, this investigation concluded that the S-octylthio derivative is a more effective growth inhibitor of Gram-positive bacteria than disulfiram and exhibits more favorable cytotoxic and metabolic parameters over disulfiram.
Assuntos
Antibacterianos/farmacologia , Dissulfiram/análogos & derivados , Dissulfiram/farmacologia , Animais , Antibacterianos/síntese química , Antibacterianos/química , Antibacterianos/toxicidade , Ciprofloxacina/farmacologia , Dissulfiram/síntese química , Dissulfiram/toxicidade , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Positivas/efeitos dos fármacos , Meia-Vida , Células Hep G2 , Humanos , Testes de Sensibilidade Microbiana , Microssomos Hepáticos/efeitos dos fármacos , Estrutura Molecular , Ratos , Vancomicina/farmacologiaRESUMO
A chemical library comprised of nineteen synthesized pyridyl disulfides that emulate the chemical reactivity of allicin (garlic) was evaluated for antimicrobial activity against a panel of pathogenic bacteria. Gram-positive species including vancomycin-intermediate and vancomycin-resistant Staphylococcus aureus (VISA, VRSA) demonstrated the highest level of susceptibility toward analogs with S-alkyl chains of 7-9 carbons in length. Further biological studies revealed that the disulfides display synergy with vancomycin against VRSA, cause dispersal of S. aureus biofilms, exhibit low cytotoxicity, and decelerate S. aureus metabolism. In final analysis, pyridyl disulfides represent a novel class of mechanism-based antibacterial agents that have a potential application as antibiotic adjuvants in combination therapy of S. aureus infections with reduced vancomycin susceptibility.
Assuntos
Antibacterianos/farmacologia , Dissulfetos/farmacologia , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Piridinas/farmacologia , Ácidos Sulfínicos/farmacologia , Antibacterianos/síntese química , Antibacterianos/química , Biofilmes/efeitos dos fármacos , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Dissulfetos/química , Relação Dose-Resposta a Droga , Humanos , Staphylococcus aureus Resistente à Meticilina/crescimento & desenvolvimento , Testes de Sensibilidade Microbiana , Estrutura Molecular , Piridinas/química , Relação Estrutura-Atividade , Ácidos Sulfínicos/químicaRESUMO
Thiolated fluoroquinolones were synthesized from ciprofloxacin and evaluated for antimicrobial activity against a panel of pathogenic bacteria. Gram-positive species including methicillin-resistant Staphylococcus aureus (MRSA) exhibited the highest level of increased sensitivity toward ciprofloxacin bound with a N-propylthio substituent. Evidence was found that the antibiotics form disulfides with low molecular weight thiols in bacteria and potentiate generation of cytosolic reactive oxygen species (ROS). In final analysis, the enhanced anti-MRSA activity of thiolated fluoroquinolones was attributed to increased cell permeability and reaction with cytosolic thiols that yields an inactive disulfide metabolite and the parent drug ciprofloxacin as an inhibitor of DNA synthesis.
