Increased expression of tumor necrosis factor-alpha in the rat hippocampus after acute homocysteine administration

J Epilepsy Res. 2011 Mar 30;1(1):6-12. doi: 10.14581/jer.11002. eCollection 2011 Mar.

Abstract

Background and purpose: This paper evaluated the effect of acute homocysteine administration on inflammatory cytokine tumor necrosis factor-alpha (TNF-α) expression and neuronal apoptosis in the rat hippocampus and investigated the effects of vitamin C treatment on homocysteine-induced inflammation and neuronal death.

Methods: Subjects were three-week-old, male Sprague-Dawley rats. Rats for the control group, we injected saline solution into the rats' abdominal cavities for one week. Rats in the second group received 1 injection of homocysteine (11 mmol/kg) into their abdominal cavities after 1 week of saline solution administration. For the third group, we injected the rats with vitamin C (100 mg/kg) for a week, followed by 1 injection of homocysteine. The hippocampi were stained with an anti-TNF-α antibody, and apoptosis was evaluated using the TUNEL staining method.

Results: The homocysteine-injected rats had strong TNF-α expression in every hippocampal region. Vitamin C significantly reduced TNF-α expression in the hippocampus's CA1 region. Acute homocysteine administration did not cause apoptosis in the hippocampus.

Conclusions: The pro-inflammatory cytokine TNF-α may mediate elevated homocysteine levels' contributions to inflammatory reactions, and vitamin C has some protective effect on inflammatory reactions in the CA1 hippocampal region.

Keywords: Apoptosis; Hippocampus; Homocysteine; TNF-α; Vitamin C.