RESUMEN
A novel class of PARP-1 inhibitors was identified containing a non-aromatic heterocycle or carbocycle fused to a pyrazolo pyridin-2-one. Compounds displayed low nanomolar binding activity in the PARP-1 binding assay and submicromolar activity in a cell based chemosensitization assay.
Asunto(s)
Inhibidores Enzimáticos , Inhibidores de Poli(ADP-Ribosa) Polimerasas , Pirazoles , Piridonas , Animales , Pollos , Técnicas Químicas Combinatorias , Diseño de Fármacos , Inhibidores Enzimáticos/síntesis química , Inhibidores Enzimáticos/química , Inhibidores Enzimáticos/farmacología , Estructura Molecular , Pirazoles/síntesis química , Pirazoles/química , Pirazoles/farmacología , Piridonas/síntesis química , Piridonas/química , Piridonas/farmacología , Relación Estructura-ActividadRESUMEN
T cell proliferative responses decrease with age, but the mechanisms responsible are unknown. We examined the impact of age on memory and naive CD4(+) T cell entry and progression through the cell cycle using acridine orange to identify cell cycle stage. For both subsets, fewer stimulated cells from old donors were able to enter and progress through the first cell cycle, with an increased number of cells arrested in G(0) and fewer cells in post G(0) phases. The number of dead cells as assessed by sub-G(0) DNA was also significantly greater in the old group. CD4(+) T cells from old mice also exhibited a significant reduction in clonal history as assessed by CFSE staining. This was associated with a significant decline in cyclin D2 mRNA and protein. We propose that decreases in cyclin D2 are at least partially responsible for the proliferative decline found in aged CD4(+) T cells.