Identification and Characterization of Risk Factors in Alzhemimer's Disease

Abstract

Alzheimer’s disease poses a steady loss of neurons, disruption of synapses and, aggregation of proteins such as tau and amyloid-beta. It influences more than 50 million people around the globe, with no preventive treatment or early diagnosis. Drugs targeting amyloid-beta accumulation have failed in clinical trials. Tau hypothesis and oxidative stress are the next strong candidates of the therapeutic and diagnostic target. This study has investigated the role of oxidative stress and related pathways involved in post-translational modulation of the ptau and prp through in vitro analysis. The three-phased study included oxidative stress induction through NaAsO3 and human CSF (cont., sAD, rpAD) in the 1st and 2nd phase respectively. The induction of stress was analyzed through immunoblotting and co-immunoprecipitation in 1st phase and cell-viability assay (MTS) and co-immunofluorescence in the 2nd phase. The third phase was to characterize the oxidative stress as a risk factor through 2D-proteomic analysis comparison of in-vitro stress-induced cell lines with that of human brain lysates (cont., sAD, rpAD). Results showed enhanced modulation and change in localization of AD-related proteins i.e., ptau, prp and SFPQ with oxidative stress marker TIA-1. A decrease in the viability of cells under oxidative stress was also observed. This confirms the disease progression role of oxidative stress linking it to the hallmark of AD through its aggregation. It also explains the pathway of neuronal cell death through cytotoxicity by means of co-localization analysis of essential aggregating proteins in AD and stress granule marker TIA-1. Further identification and characterization of important molecular factors contributing to the pathways of oxidative stress in AD as well as other neurodegenerative diseases will add in to a better understanding of its mode of action and mechanism. A mass-spectrometric analysis of the interacting partners of oxidative stress markers will give further insights into new therapeutic and diagnostic targets.