Alzheimer’s disease is a progressive neurological disorder characterized by behavioural changes, memory loss and cognitive dysfunction. It has an important role in public health since tens of millions of people are diagnosed with it and it is the most common cause of dementia. The amyloid plaques that appear in the patient’s brain consist of aggregated peptide amyloid beta (Aβ). Amyloid plaques prevent proper neuronal function and cause neurodegeneration. Aβ peptide regulates the expression of genes in neurons that play an important role in synaptic function, inflammation and apoptosis. Consequently, the homeostasis is disrupted, neuroinflammation is accelerated and signalling between neurons is damaged.
In in vitro tests Aβ specifically binds to protein profilin 1 that regulates actin polymerization. Profilin 1 regulates synaptic plasticity and morphology of neurons. The goal of this master’s thesis is to determine whether Aβ1-42 regulates the expression of the PFN1 gene. We exposed human neuroblastoma cell line SH-SY5Y to Aβ1-42. During the experiment we changed the form and concentration of Aβ1-42. Then we isolated RNA from the cells. Using reverse transcription polymerase chain reaction we prepared the samples for real-time polymerase chain reaction. In this way we obtained data of the expression of the PFN1 gene in cells after exposure to Aβ1-42. Simultaneously we analysed four additional genes under the same conditions in the same samples: ATF3, DKK1, IGFBP and LMO3. For those genes it is known that Aβ regulates their expression.
By exposing SH-SY5Y cells to fibrils or monomers of Aβ1-42 we discovered an increasing trend of the expression of the PFN1 gene. The results are consistent with the previously known increased trend of profilin 1 content in SH-SY5Y cells after the exposure to Aβ1-42. The expression of the PFN1 gene is time dependent with a maximum difference of expression after 8 h of exposure of cells to Aβ1-42. The change factor of expression of the PFN1 gene is 1,1–1,2.
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