NF-kB immunoreactivity is observed in association with beta A4 diffuse plaques in patients with Alzheimer's disease.
Transcription factor NF-kB is widely expressed in the nervous system and, particularly, in synaptic terminals. Increased NF-kB expression in synaptosomes has been observed as a result of activity, and beta A4 deposition. In the present study we have examined NF-kB immunoreactivity, by means of NF-kB p65 immunohistochemistry, in the brains of seven patients with Alzheimer's disease, two patients with Creutzfeldt-Jakob disease associated with PrP amyloid deposition, and seven age-matched controls. Our purpose was to examine possible NF-kB induction associated to beta A4 or PrP deposition in these diseases. Punctate NF-kB immunoreactivity was constantly found in the neuropil of diffuse beta A4 deposits but not in dystrophic neurites of senile plaques. In addition, NF-kB immunoreactivity was found in the nuclei of neurons, but not in the nuclei of reactive astrocytes, in the vicinity of diffuse plaques, thus suggesting NF-kB translocation to the nucleus. Finally, a few neurons with neurofibrillary degeneration showed increased cytoplasmic NF-kB immunoreactivity probably secondary to abnormal compartmentation or impaired transport of NF-kB. No similar modifications in NF-kB immunoreactivity were observed in association with PrP deposits in patients with Creutzfeldt-Jakob disease. Since it has been suggested that the presence of NF-kB in synapses may indicate the existence of a new pathway of gene transcription, the present results support the concept that this pathway may be activated by the deposition of beta A4 in diffuse plaques in Alzheimer's disease.
Unitat de Neuropatologia, Hospital Princeps d'Espanya, Spain.
I
I
Ferrer
E
E
Martí
E
E
López
A
A
Tortosa
D000544:Alzheimer Disease / Q000378:metabolism* / Q000473:pathology; D016229:Amyloid beta-Peptides / Q000032:analysis* / Q000276:immunology; D000906:Antibodies; D001923:Brain Chemistry; D007562:Creutzfeldt-Jakob Syndrome / Q000378:metabolism / Q000473:pathology; D005904:Glial Fibrillary Acidic Protein / Q000032:analysis / Q000276:immunology; D006801:Humans; D016328:NF-kappa B / Q000032:analysis* / Q000276:immunology; D058225:Plaque, Amyloid / Q000737:chemistry; D011328:Prions / Q000032:analysis / Q000276:immunology
D016229:Amyloid beta-Peptides; D000906:Antibodies; D005904:Glial Fibrillary Acidic Protein; D016328:NF-kappa B; D011328:Prions