Immunohistochemical localization of redox factor-1 (Ref-1) in Alzheimer's hippocampus

REDOX factor-1 (Ref-l) is a dual-function protein involved in both DNA repair and transcriptional regulation. Ref-l is modulated by cerebral ischemia and other oxidative stressors, and also regulates the DNA-binding activities of transcription factors implicated in Alzheimer's disease (AD)-related neurodegeneration. The present study examined Ref-l expression in the AD hippocampus by immunohistochemistry. Although Ref-1 immunostaining was relatively low in control brain sections, senile plaques and other plaque-like structures in the AD brain were Ref-l-positive. Cells with increased Ref-l immunoreactivity were also observed in regions of neuronal injury. These results suggest that Ref-l might contribute to senile plaque formation, and that overexpression of Ref-l in injured neurons may be part of a response to oxidative stress and an attempt to repair damaged DNA in AD. (C) 1998 Lippincott Williams & Wilkins.