α-synuclein as a promising biomarker for developing diagnostic tools against neurodegenerative synucleionopathy disorders

Synucleinopathies are multifactorial neurodegenerative disorders marked by the presence of intracellular deposits of α-synuclein (α-syn) protein. Although significant progress has been made in understanding the pathogenesis of synucleinopathies, diagnosis largely relies on the clinical symptoms and histopathological analyses. A major challenge is the lack of diagnostic tests for identifying disease biomarkers. As aggregation of α-syn is one of the key indicators of disease, this protein is of interest as a target biomarker for the development of diagnostic platforms. In this review, we outline emerging evidence that highlights the importance of α-syn as a reliable biomarker for synucleinopathies. We present a comprehensive overview of the underlying principle of different methods available for the detection of α-syn which either use molecular recognition elements (MREs) to obtain specificity, or direct detection where specificity is obtained by using sensor components. Finally, the review provides a critical outlook on the current trends and challenges in α-syn based disease diagnosis and makes recommendations for the steps needed to achieve full diagnostic potential of the available methods.