P2‐512: Identifying endogenous anti‐amyloid compounds

Since peptide sequences other than ß-amyloid are susceptible to aggregation (the “amylome”), there is evolutionary pressure to inhibit deleterious protein-misfolding; accordingly, it is reasonable to postulate the existence of endogenous anti-aggregation molecules that could arrest the neurotoxic cascade of AD. From the Aß perspective, compounds binding to the EVHHQKLVFF basic residues of Aß could in principle interrupt glycosaminoglycan/ß-amyloid interactions, inhibiting neurotoxic aggregation. Searching for an “endogenous anti-AD compound” represents an unexplored concept in AD therapeutics design. An in silico to in vitro approach was employed. We created a comprehensive in silico library of 1,450 molecules (molecular weight less than 600 g/mol) that are endogenous to the human brain. These compounds were then screened in silico, using a molecular mechanics/molecular dynamics approach, for ability to bind to the EVHHQKLVFF region of Aß. Compounds identified in this in silico screen were then experimentally evaluated using in vitro assays (ThT, CD, MTT cell viability, EM aggregation) to assess their capacity to inhibit Aß aggregation and related neurotoxicity. To identify an endogenous anti-protein-misfolding compound, we devised a computational model of non-neurotoxic, unaggregated Aß; next, we devised an in silico strategy to screen a library of endogenous compounds for molecules capable of binding Aß's HHQK/BBXB domain. This identified a family of L-phosposerine metabolites as endogenous anti-aggregants. We next performed in vitro assays to assess the capacity of these compounds to inhibit Aß aggregation. L-phosphoserine was able to block Aß aggregation in a Thioflavin-T aggregation assay (IC-50 = 3.4 micromolar); to prevent Aß conformational change from helix to ß-sheet in circular dichroism studies; to bind to Aß (at HHQK) in mass spectrometry and NMR studies; to prevent Aß aggregation in electron microscopy studies; and to prevent Aß cellular toxicity in an (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium (MTT) assay. Therefore, L-phosphoserine is an endogenous Aß anti-aggregant. An in silico screening strategy has identified a class of endogenous compounds that is able to inhibit Aß aggregation in vitro. Significantly, it is also known that L-phosphoserine neurochemistry is abnormal in AD patients; e.g. L-phosphoserine is one of the neural phosphomonoesters that is elevated in Alzheimer's disease brain.

Récupéré en direct depuis OpenAlex et désinversé. Les résumés ne sont pas conservés dans cette base de données : les index inversés représentent 8,6 Go des 9,3 Go de texte de la base, et le serveur dispose de 13 Go libres.