Research from Poland could lead to a better understanding of the causes of Parkinson's disease. Teresa Kowalik-Jankowska from the University of Wroclaw and her colleagues have studied how copper-catalysed oxidation damages a protein linked to the condition. 

Patients with Parkinson's disease have significantly increased copper levels in their cerebrospinal fluid, suggesting that the metal is somehow involved in promoting the condition, said Kowalik-Jankowska. The protein alpha-synuclein plays a central role in a number of neurodegenerative diseases and oxidation with copper(II) ions is known to cause it to aggregate in vitro. alpha-Synuclein aggregation in vivo is believed to trigger lesions called Lewy bodies to form, added Kowalik-Jankowska, and these abnormal protein deposits are found in the brains of patients with Parkinson's disease. 

To examine the precise role of copper in alpha-synuclein aggregation, the Polish team studied how copper(II) ions interact with fragments of a mutant form of alpha-synuclein that is particularly prone to aggregation. They found that the ions bind to the peptide fragments primarily through histidine, methionine and lysine residues. Copper binding makes these residues more susceptible to reaction under oxidising conditions, said Kowalik-Jankowska. 'We can say that copper(II) ions will react in a similar way with the whole protein.' 

In future research, the group will take a closer look at the products formed by copper(II)-catalysed oxidation of fragments of non-mutant alpha-synuclein.

Danièle Gibney