Basic Science and Pathogenesis.

Background: Heparan sulfate (HS) interacts with many important proteins. These interactions are primarily driven by electrostatics, with specificity determined by sulfation patterns. Although 3-O-sulfation is a rare modification in HS, several genome-wide association studies (GWAS) revealed that the Hs3st1 gene, encoding HS-3-O-sulfotransferase-1, is significantly linked to late onset AD risk.

Apolipoprotein E Recognizes Alzheimer's Disease Associated 3-O Sulfation of Heparan Sulfate.

Apolipoprotein E (ApoE)'s ϵ4 alle is the most important genetic risk factor for late onset Alzheimer's Disease (AD). Cell-surface heparan sulfate (HS) is a cofactor for ApoE/LRP1 interaction and the prion-like spread of tau pathology between cells. 3-O-sulfo (3-O-S) modification of HS has been linked to AD through its interaction with tau, and enhanced levels of 3-O-sulfated HS and 3-O-sulfotransferases in the AD brain.

The Sulfation Code of Tauopathies: Heparan Sulfate Proteoglycans in the Prion Like Spread of Tau Pathology.

Tauopathies are a heterogenous family of progressive neurodegenerative diseases defined by the appearance of proteinaceous lesions within the brain composed of abnormally folded species of Microtubule Associated Protein Tau (tau). Alzheimer's Disease (AD), the most common tauopathy, is the leading cause of cognitive decline among the elderly and is responsible for more than half of all cases of senile dementia worldwide. The characteristic pathology of many tauopathies-AD included-presents as Neurofibrillary Tangles (NFTs), insoluble inclusions found within the neurons of the central nervous system composed primarily of tau protein arranged into Paired Helical Fibrils (PHFs).