RESUMO
Cationic and non-peptide small molecules containing a total of six positive charges arranged on one side and a long aliphatic tail on the other have been synthesized and tested against Gram-positive and Gram-negative bacteria. The positive charges have been contributed by two aminophenol residues. These molecules have showed remarkable antimicrobial activity against Gram-positive bacteria including multidrug-resistant strains. Our structureâ»activity relationship studies demonstrated the importance of the length and flexibility of the hydrophobic tail for the antimicrobial activity. Importantly, these compounds are non-toxic to eukaryotic cells at the concentration affecting growth in bacteria, reflecting an acceptable margin of safety. The small size and easy synthetic accessibility of our molecules can be of interest for the further development of novel antimicrobials against Gram-positive bacterial pathogens, including multidrug-resistant strains.
Assuntos
Antibacterianos/síntese química , Peptídeos Catiônicos Antimicrobianos/síntese química , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Positivas/efeitos dos fármacos , Bibliotecas de Moléculas Pequenas/síntese química , Aminofenóis/química , Antibacterianos/farmacologia , Peptídeos Catiônicos Antimicrobianos/farmacologia , Cátions , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Fibroblastos/citologia , Fibroblastos/efeitos dos fármacos , Bactérias Gram-Negativas/crescimento & desenvolvimento , Bactérias Gram-Positivas/crescimento & desenvolvimento , Células HeLa , Humanos , Interações Hidrofóbicas e Hidrofílicas , Testes de Sensibilidade Microbiana , Bibliotecas de Moléculas Pequenas/farmacologia , Especificidade da Espécie , Eletricidade Estática , Relação Estrutura-AtividadeRESUMO
New series of polyphenols with a hydrophilic galloyl-based head and a hydrophobic N-acyl tail, linked through a serinol moiety, have been synthesized and tested against colon cancer cell growth. Our structure activity relationship studies revealed that galloyl moieties are essential for growth inhibition. Moreover, the length of the N-acyl chain is crucial for the activity. Introduction of a (Z) double bond in the acyl chain increased the anticancer properties. Our findings demonstrate that 16, the most potent compound within this series, has inhibitory effects on colon cancer cell growth and metabolism (glycolysis and mitochondrial respiration) at the same time that it activates 5'AMP-activated kinase (AMPK) and induces apoptotic cell death. Based on these results, we propose that 16 might reprogram colon cancer cell metabolism through AMPK activation. This might lead to alterations on cancer cell bioenergy compromising cancer cell viability. Importantly, these antiproliferative and proapoptotic effects are selective for cancer cells. Accordingly, these results indicate that 16, with an unsaturated C18 chain, might be a useful prototype for the development of novel colon cancer cell growth inhibitors affecting cell metabolism.
