RESUMO
Herein we report the discovery of a family of novel yet simple, amino-acid derived class I HDAC inhibitors that demonstrate isoform selectivity via access to the internal acetate release channel. Isoform selectivity criteria is discussed on the basis of X-ray crystallography and molecular modeling of these novel inhibitors bound to HDAC8, potentially revealing insights into the mechanism of enzymatic function through novel structural features revealed at the atomic level.
Assuntos
Ácido Acético/metabolismo , Aminoácidos/química , Aminoácidos/farmacologia , Inibidores de Histona Desacetilases/química , Inibidores de Histona Desacetilases/farmacologia , Histona Desacetilases/metabolismo , Cristalografia por Raios X , Desenho de Fármacos , Histona Desacetilases/química , Humanos , Modelos Moleculares , Isoformas de Proteínas/química , Isoformas de Proteínas/metabolismoRESUMO
A novel 2,6-naphthyridine was identified by high throughput screen (HTS) as a dual protein kinase C/D (PKC/PKD) inhibitor. PKD inhibition in the heart was proposed as a potential antihypertrophic mechanism with application as a heart failure therapy. As PKC was previously identified as the immediate upstream activator of PKD, PKD vs PKC selectivity was essential to understand the effect of PKD inhibition in models of cardiac hypertrophy and heart failure. The present study describes the modification of the HTS hit to a series of prototype pan-PKD inhibitors with routine 1000-fold PKD vs PKC selectivity. Example compounds inhibited PKD activity in vitro, in cells, and in vivo following oral administration. Their effects on heart morphology and function are discussed herein.
Assuntos
Aminopiridinas/síntese química , Naftiridinas/síntese química , Proteína Quinase C/antagonistas & inibidores , Transporte Ativo do Núcleo Celular , Administração Oral , Aminopiridinas/farmacocinética , Aminopiridinas/farmacologia , Animais , Anti-Hipertensivos/síntese química , Anti-Hipertensivos/química , Anti-Hipertensivos/farmacologia , Pressão Sanguínea/efeitos dos fármacos , Cardiomegalia/tratamento farmacológico , Cardiomegalia/patologia , Núcleo Celular/metabolismo , Histona Desacetilases/metabolismo , Isoenzimas/antagonistas & inibidores , Masculino , Modelos Moleculares , Células Musculares/efeitos dos fármacos , Células Musculares/metabolismo , Células Musculares/patologia , Miocárdio/metabolismo , Miocárdio/patologia , Naftiridinas/farmacocinética , Naftiridinas/farmacologia , Fosforilação , Ligação Proteica , Ratos , Ratos Endogâmicos Dahl , Ratos Sprague-Dawley , Relação Estrutura-AtividadeRESUMO
A series of lysine-based oligomers (18 residues) that differ in side chain configuration or side chain spacing along the backbone was tested for DNA transfection activity. Although materials constructed from lysine are not the most effective polymeric transfection agents, we have chosen L-lysine-based molecules as a starting point because this system allows us to examine the functional effects of incremental changes in polycation structure. The oligomer constructed from beta(3)-homolysine (beta(3)-hLys) and that from alpha-D-lysine were superior to an alpha-L-lysine 18-mer in gene delivery assays. This improved activity is attributed to the fact that the alpha-L-peptide is a protease substrate while the other 18-mers are not. This conclusion is supported by the effects of chloroquine on transfection activity, based on the protease inhibition activity of chloroquine. To our knowledge, these results represent the first direct comparison of a D-lysine oligomer with an L-lysine oligomer in the context of gene delivery. Poly(beta(3)-hLys) was synthesized from the ring opening polymerization of the corresponding lactam. The DNA transfection ability of this polymer was compared with that of commercially available poly(L-lysine) (PLL). In each case the polymer was more active than the corresponding oligomer.