Niskocząsteczkowe inhibitory szlaku adaptacyjnej odpowiedzi na stres zależnego od kinazy PERK jako nowatorska strategia terapeutyczna w leczeniu choroby Alzheimera

: The characteristic hallmark of Alzheimer's disease (AD) are progressive changes in the brain structure and function, caused by aggregation of senile plagues, composed of improperly folded amyloid β(Aβ) protein, in the brain tissue. Recent research has suggested that causes of AD are closely associated with perturbation on the molecular level caused by the activation of the pro-apoptotic, PERKdependent Unfolded Protein Response (UPR) signaling pathway activated under Endoplasmic Reticulum (ER) stress conditions. AIM: The aims of the study were evaluation of the activity of the smallmolecule inhibitors of PERK kinase, GSK2606414 and LDN-0060609, via the analysis of the level of the phosphorylation of eIF2α as one of the main markers of the UPR signaling pathway activation as well as evaluation of the cytotoxicity of the inhibitor LDN-0060609. MATERIALS AND METHODS: The study was conducted on commercially available cell lines of wild type mouse embryotic fibroblasts 3T3 MEFs WT and with deletion of PERK gene 3T3 MEFs KO, mouse neurons CATH.a and human neuroblastoma SH-SY5Y with overexpression of amyloid precursor protein (APP). Cells were treated with commercially available inhibitor GSK2606414 or LDN-0060609, selected from the small-molecule compounds library Laboratory for Drug Discovery in Neurodegeneration, on appropriate cell culture medium with thapsigargin as an activator of Endoplasmic Reticulum (ER) stress conditions. To evaluate the level of eIF2α phosphorylation we used the Western blot technique. Detection of immune complexes was performed using the chemiluminescence. Evaluation of the LDN-0060609 compound cytotoxicity was carried out on SH-SY5Y cells using the XTT assay. RESULTS: The results of the study showed that the commercially available GSK2606414 inhibitor at a concentration of 1 μM causes >85% inhibition of the phosphorylation of eIF2α in all tested cell lines. The newly tested LDN-0060609 inhibitor showed the highest inhibitory activity at 25 μM resulting in 52% inhibition of eIF2α phosphorylation. In addition, the LDN-0060609 inhibitor did not induce a cytotoxic effect at any used concentrations and incubation times. Conclusions. It is believed that the LDN-0060609. CONCLUSIONS: It is believed that the LDN-0060609 inhibitor, that in comparison with commercially available GSK2606414 inhibitor does not evoke a cytotoxic effect, may constitute a potential factor inhibiting activation of the PERK-dependent UPR signaling pathway responsible for neurodegenerative processes in AD. Small-molecule PERK inhibitors may constitute an innovative therapeutic strategy for AD treatment.