title: NF-kappaB dimers in the regulation of neuronal survival.
abstract: Nuclear factor-kappaB (NF-kappaB) is a dimeric transcription factor composed of five members, p50, RelA/p65, c-Rel, RelB, and p52 that can diversely combine to form the active transcriptional dimer. NF-kappaB controls the expression of genes that regulate a broad range of biological processes in the central nervous system such as synaptic plasticity, neurogenesis, and differentiation. Although NF-kappaB is essential for neuron survival and its activation may protect neurons against oxidative-stresses or ischemia-induced neurodegeneration, NF-kappaB activation can contribute to inflammatory reactions and apoptotic cell death after brain injury and stroke. It was proposed that the death or survival of neurons might depend on the cell type and the timing of NF-kappaB activation. We here discuss recent evidence suggesting that within the same neuronal cell, activation of diverse NF-kappaB dimers drives opposite effects on neuronal survival. Unbalanced activation of NF-kappaB p50/RelA dimer over c-Rel-containing complexes contributes to cell death secondary to the ischemic insult. While p50/RelA acts as transcriptional inducer of Bcl-2 family proapoptotic Bim and Noxa genes, c-Rel dimers specifically promote transcription of antiapototic Bcl-xL gene. Changes in the nuclear content of c-Rel dimers strongly affect the threshold of neuron vulnerability to ischemic insult and agents, likewise leptin, activating a NF-kappaB/c-Rel-dependent transcription elicit neuroprotection in animal models of brain ischemia.
authors.affiliation: Division of Pharmacology and Experimental Therapeutics, Department of Biomedical Sciences and Biotechnologies, School of Medicine, University of Brescia, Brescia 25123, Italy.
authors.forename: Ilenia
authors.initials: I
authors.lastname: Sarnico
authors.forename: Annamaria
authors.initials: A
authors.lastname: Lanzillotta
authors.forename: Marina
authors.initials: M
authors.lastname: Benarese
authors.forename: Manuela
authors.initials: M
authors.lastname: Alghisi
authors.forename: Cristina
authors.initials: C
authors.lastname: Baiguera
authors.forename: Leontino
authors.initials: L
authors.lastname: Battistin
authors.forename: Pierfranco
authors.initials: P
authors.lastname: Spano
authors.forename: Marina
authors.initials: M
authors.lastname: Pizzi
mesh_terms: D000818:Animals; D001921:Brain / Q000378:metabolism / Q000502:physiology; D002545:Brain Ischemia / Q000378:metabolism* / Q000473:pathology*; D016923:Cell Death / Q000502:physiology; D002470:Cell Survival / Q000502:physiology*; D019281:Dimerization; D016328:NF-kappa B / Q000096:biosynthesis / Q000502:physiology*; D009474:Neurons / Q000378:metabolism / Q000473:pathology* / Q000502:physiology*; D015533:Transcriptional Activation
chemical_list: D016328:NF-kappa B