Getting Insight into the Molecular Determinants of Foldopathies

The study of the molecular determinants of foldopathies is an urgent task to be addressed because of the huge number of people inflected by these severe diseases. Foldopathies are diseased linked to protein misfolding and include widespread diseases, such as Parkinson’s and Alzheimer’s disorders. In this project, the aim is to tackle some common factors that could trigger the onset of these disorders which are linked to protein aggregation. These include protein aggregation, clearance systems, therapeutic compounds oxidative stress, post-translational modifications (metal ions and oxidative reactive species) and cross-seeding among amyloidogenic proteins. Since the protein aggregation is a common pathological pathway, the biochemical events that may affect this process are investigated, either singularly or in combination. The proteins alpha synuclein and amyloid beta were the focus of this research. The optimization of protein purification protocol to produce the protein α-synuclein was the initial step. The protein was studied in the presence of Copper(II) and Acrolein using mass spectrometry for the determination of the interaction site which was Histidine 50. The site was further confirmed by additional studies with circular dichroism, dynamic light scattering and synthesized short peptide containing Histidine 50. Malondialdehyde was also studied for its interaction with Histidine 50. Next, the interaction of this protein with hydroxyquinoline derivatives, for their therapeutic properties, was carried out using native mass spectrometry, fluorescence aggregation assay and other techniques. Additionally, alpha synuclein oligomers were studied as well as its interaction with amyloid beta in the presence of insulin degrading enzyme. This enzyme and its mutant were also recruited in order to understand the involvement of metal ions copper(II) and Zinc(II) in the degradation process. Finally, the proteasome 20S from the clearance system was utilized to understand the hydrolysis of different peptide fragments of amyloid beta in the absence and/or the presence of potentially therapeutic compound. The complexity of this class of disorders arises from the involvement of numerous proteins each linked to a different disease creating a complex web of factors to be considered when conducting studies. Hence, identifying some “common grounds” to minimize the complexity of the study is a logical approach for foldopathies. Numerous promising results are reported, but this area of studies is still ongoing. The in-depth understanding of the factors involved in the early stages of the disorders could represent an important achievement for the development of customized therapeutic approaches.