Clinical Neuroscience

[The role of immobilization stress and sertindole on the expression of APP, MAPK-1 and β-actin genes in rat brain]

KÁLMÁN János, PÁKÁSKI Magdolna, SZŰCS Szabina, KÁLMÁN Sára, FAZEKAS Örsike, SÁNTHA Petra, SZABÓ Gyula, JANKA Zoltán, KÁLMÁN János

NOVEMBER 20, 2012

Clinical Neuroscience - 2012;65(11-12)

[Stress, depending on its level and quality, may cause adaptive and maladaptive alterations in brain functioning. As one of its multiple effects, elevated blood cortisol levels decrease the synthesis of the neuroprotective BDNF, thus leading to hippocampal atrophy and synapse loss, and rendering it a possible cause for the Alzheimer’s disease (AD) related neuropathological and cognitive changes. As a result of the stress response, intraneuronal alterations - also affecting the metabolism of β-actin - can develop. These have a role in the regulation of memory formation (LTP), but in pathological conditions (AD) they could lead to the accumulation of Hirano bodies (actin-cofilin rods). According to the dementia treatment guidelines, the behavioural and psychological symptoms of AD can be treated with certain antipsychotics. Therefore, the aim of our study was to examine the effects of sertindole (currently not used in the standard management of AD) on the transcription of some AD associated genes (amyloid precursor protein [APP], mitogen activated protein kinase-1 [MAPK-1], β-actin) in the brain of rats exposed to chronic immobilization stress (CIS). Male Wistar rats were exposed to CIS for three weeks. The four groups were: control (n=16), CIS (n=10), 10 mg/kg sertindole (n=5) and 10 mg/kg sertindole + CIS (n=4). Following transcardial perfusion, the relative levels of hippocampal and cortical mRNA of the previously mentioned genes were measured with real-time PCR. CIS induced hippocampal β-actin (p<0.01), MAPK-1 and APP (p<0.05) mRNA overexpression. The simultaneous administration of sertindole suppressed this increase in β-actin, MAPK-1 and APP expression (p<0.05). Ours is the first report about CIS induced β-actin gene overexpression. This finding, in accordance with the similar results in APP and MAPK-1 expression, underlines the significance of cytoskeletal alterations in AD pathogenesis. The gene expression reducing effect of sertindole suggests that antipsychotic drugs may have a neuroprotective effect.]

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