RESUMEN
The activation of NF-kappaB inhibits apoptosis via a mechanism involving upregulation of various antiapoptotic genes, such as cellular FLICE-inhibitory protein (c-FLIP), Bcl-xL, A1/Bfl-1, and X chromosome-liked inhibitor of apoptosis (XIAP). In contrast, the activation of c-Jun N-terminal kinase (JNK) promotes apoptosis in a manner that is dependent on the cell type and the context of the stimulus. Recent studies have indicated that one of the antiapoptotic functions of NF-kappaB is to downregulate JNK activation. Further studies have also revealed that NF-kappaB inhibits JNK activation by suppressing accumulation of reactive oxygen species (ROS). In this review, we will focus on the signaling crosstalk between the NF-kappaB and JNK cascades via ROS.
Asunto(s)
Proteínas Quinasas JNK Activadas por Mitógenos/metabolismo , FN-kappa B/fisiología , Especies Reactivas de Oxígeno/metabolismo , Transducción de Señal , Animales , Apoptosis , Regulación hacia Abajo , Drosophila , Ratones , Modelos Biológicos , Factor de Necrosis Tumoral alfa/farmacologíaRESUMEN
The intestinal Peyer's patches (PP) were significantly different in distribution and fine morphology between Mongolian gerbils and mice. The PP of gerbils were evenly distributed from the duodenum to ileum, whereas the PP of mice were more densely distributed in the lower ileum than other parts of the intestine. In gerbils, each PP had a much greater number of lymphoid follicles than in mice, although the total number of PP was smaller. Electron microscopy revealed that the PP dome of gerbils was covered with two types of epithelial cells, one with shorter microvilli and the other with longer ones, whereas the epithelial cells of the murine PP dome was uniform-shaped with numerous medium-sized microvilli. Some dome absorptive cells of gerbils were morphologically similar to poorly differentiated crypt cells of mice, suggesting to be immature M cells.