Phosphorylation of 14-3-3ζ at serine 58 and neurodegeneration following kainic acid-induced excitotoxicity

Oxidative stress-induced cell death leads to phosphorylation of 14-3-3 zeta at serine 58. 14-3-3 zeta is detected at significant levels in cerebrospinal fluid after kainic acid (KA)-induced seizures. Here we examined temporal changes in 14-3-3 zeta phosphorylation in the hippocampus and amygdala of mice after KA treatment. Mice were killed at 2, 6, 24, or 48 h after KA (30 mg/kg) injection. We observed an increase in TUNEL and Fluoro-Jade B (FJB)-stained neurons in the hippocampus and amygdala of KA-treated mice. Phospho (p)-14-3-3 zeta and p-JNK expression was increased in the hippocampus 2 and 6 h after KA treatment, respectively. In immunohistochemical analysis, p-14-3-3 zeta-positive cells were present in the CA3 region of the hippocampus and the central nucleus of amygdala (CeA) of KA-treated mice. Thus, phosphorylation of 14-3-3 zeta at serine 58 may play an important role in KA-induced hippocampal and amygdaloid neuronal damage.