Abstract

Neurodegenerative disorders such as Alzheimer’s Disease (AD) and Parkinson’s Disease are persistent, progressive diseases, and they are associated with abnormal accumulation and aggregation of disease-specific proteins and peptides and inclusion bodies in selected brain regions. AD is the most common form of diagnosed dementia, and it is associated with a decline in cognitive ability and premature death. AD is the sixth main cause of death in the USA, and it has been a major public health problem for which there is currently no disease-modifying treatment. This is mainly caused by the non-definitive hypothesis of the root cause of this disease. It has been proposed that the beta-amyloid peptide (Aβ), abnormal tau protein, or probably both play critical roles in AD development, leading to the formation of senile plaques and neurofibrillary tangles, thus making them promising targets for next-generation drug therapies. To date, there has been a growing knowledge of the underlying cause of AD and multiple active clinical trials for potential treatments.

In this presentation, recent progress in the understanding of AD pathogenesis will be discussed, with emphasis on the amyloid cascade hypothesis and the Aβ aggregation mechanism. Natural products with neuroprotective activities are believed to hold significant promise in preventing or treating AD, especially through inhibition of the Aβ oligomer formation, which is considered to be the most toxic amyloid species. Our approach combines in vitro screening followed by in vivo evaluation of several bioactive antioxidants as novel aggregation inhibitors. In particular, electrospray ionization-ion mobility spectrometry- mass spectrometry (ESI-IMS-MS) study of the Aβ(1-40): crocin samples combined with the TEM study reveal a substantial perturbation of the typical amyloid fibril forming pathway and alteration in the monomer/oligomer distribution of Aβ(1-40) induced by the crocin interaction. Our findings highlight the utility of dietary antioxidant screening for identifying lead compounds as a promising way to prevent amyloid toxicity and provide protection against AD.