The Hunt for the Cause of Dementia: New Hope

By Shlomo  Maital

       prion           prions

  The latest issue of Scientific American (May 2013) describes vividly how scientists are on the trail to find the cause of Alzheimer’s and dementia, leading to hope for a cure.  We have known for years that Alzheimer’s is caused by clumps of proteins that lump together and destroy brain cells.  This has been known since 1906, when Alois Alzheimer identified the plaque linked to the disease.

         But why and how does this happen?

          A scientist, Stanley B. Prusiner, U. California San Francisco, found, in a series of brilliant experiments, what causes the brain to become like “Swiss cheese” in some diseases.   

      The culprit?  An innocuous protein, PrP, which when ‘misfolded’, causes other proteins to become mis-shaped, which in turn ‘infect’ other proteins, creating clumps that do great damage.  Prusiner called these protions ‘prions’ (proteinaceous infectious particles).  Of course, when he published his findings, scientists pooh-poohed them, doubting that a protein could act like a virus, infecting other proteins.  But in 1997 Prusiner won the Nobel Prize for his breakthrough.    

    Today we know prions cause “mad cow disease” (Creutzfeld-Jacob) and evidence grows that prions also cause Alzheimer’s and dementia.  Prions begin in one part of the brain, spread to other parts, eventually reaching the brain’s deepest reaches. 

     Now, what causes ‘prions’?   And is there a therapy that can halt their spread, or reverse it?   Some day, notes the Scientific American, “prion-like seeded protein aggregation may explain the origin of some of the most feared diseases of old age – and day translate into treatments that alter the relentless progression of neurodegenerative illnesses”. 

   Let’s hope!