Prions are infectious agents responsible for neurodegenerative diseases such as bovine spongiform encephalitis (commonly known as « mad cow disease ») and CreutzfeldtJakob disease in humans.
Since the discovery in the 60s that an incurable and fatal disease could be caused by an infectious agent formed by nothing but converted misfolded proteins, the mechanisms responsible for the conversion of a normal prion protein into its infectious counterpart the scrapie prion have been relentlessly investigated. Researchers now know that once converted into the scrapie form, these abnormal proteins have the ability to sequestrate normal proteins, which are then converted to form an increasing aggregate of fibrils that builds up mainly in the brain.
More recently, several studies have suggested that a yet unknown cofactor plays a role in the process of conversion from a normal prion into the scrapie form. Among the factors potentially involved in the process are molecules belonging to the family of glycosaminoglycans, or simply GAGs. In fact, GAGs have been implicated in several degenerative diseases, including prion diseases. However, while some studies point to these molecules as the culprit for prion conversion, others suggest an opposite effect in which the molecules protect against prion conversion.
In a paper entitled « Heparin binding confers prion stability and impairs its aggregation » and published ahead of print in The FASEB Journal, the group now unveils more details on heparin and prion conversion and presents additional evidence that might help explain the conflicting results previously reported.
Source: Science Codex