ACUTE AND CHRONIC STRESS INDUCED CHANGES IN GENE TRANSCRIPTIONS RELATED TO ALZHEIMER'S DISEASE

Preclinical and clinical studies demonstrate that stress may be implicated in the risk of neurodegenerative diseases such as Alzheimer's disease (AD). Our study aimed to investigate the effects of acute and chronic immobilization stress (IS) on the gene transcriptions of beta-actin, amyloid precursor protein (APP) and mitogen activated protein kinase-1 (MAPK-1), proteins related to synaptic plasticity and neuronal degeneration. Male Wistar rats were exposed to IS for five hours daily for 3 days (acute stress) or through 7-14-21 days (chronic stress). At the end of exposure periods, total RNA was purified from the cortex and hippocampus. The amounts of beta-actin, APP and MAPK-1 mRNA were determined with real time PCR method. Our results indicate that the mRNA expression of beta-actin and APP followed a U-shaped time-response curve. Both acute and chronic IS caused a significant increase in beta-actin and MAPK-1 mRNA expression. Significant APP mRNA elevation was observed only by the 3rd week after RS. Our findings demonstrate that both acute and chronic IS lead to gene transcriptional changes of beta-actin, APP and MAPK-1. These proteins maintain the normal function of the cytoskeleton and the synaptic plasticity. The above changes may lead to cognitive deterioration, and the development of AD.