Modulation of neural-immune interactions by estrogen in the spleens of ovariectomized (OVX) middle-aged female rats was examined. Con A-induced lymphoproliferation, splenic tyrosine hydroxylase (TH) and nerve growth factor (NGF) expression, levels of p-ERK 1/2, p-CREB, and p-Akt, and activity of superoxide dismutase decreased in OVX rats while estrogen treatment enhanced their expression, levels, and activity. Also, estrogen treatment enhanced Con A-induced IFN-γ production and decreased Con A-induced IL-2 production compared to OVX animals. In contrast, estrogen increased the extent of lipid peroxidation and protein carbonyl formation while OVX induced a decline in protein carbonyl formation. These results suggest that estrogen enhances neural-immune interactions while simultaneously affecting it through generation of free radicals as reflected by increased lipid peroxidation and protein carbonyl formation.
Keywords: Akt; CREB; Cytokine; ERK; Nerve growth factor; Tyrosine hydroxylase.
Copyright © 2013 Elsevier B.V. All rights reserved.