Desórdenes neurológicos

Homocysteine and Parkinsons Disease: A Complex Relationship

Abstract

Gayle Helane Doherty

The scientific literature contains a multitude of papers linking homocysteine to poor health. Elevated homocysteine levels have been linked to cardiovascular disorders, an increased risk of fractures in the elderly and to neurological conditions. Parkinson’s Disease is the second most prevalent neurodegenerative disorder after Alzheimer’s disease. It is characterised primarily by the loss of dopaminergic neurons of the substantia nigra pars compacta leading to movement disorders. In vitro data has demonstrated a marked deleterious effect of homocysteine on the neurons that die in Parkinson’s. Yet population-based studies reveal mixed results as to whether or not elevated homocysteine is a risk factor for Parkinson’s development. Nonetheless it is well known that the use of levodopa to alleviate symptoms of Parkinson’s leads to hyperhomocysteinemia, and that patients with the highest levels of homocysteine deteriorate faster than those with lower homocysteine titres. Thus homocysteine is of clinical significance for Parkinson’s patients and a fuller understanding of its effects on neuronal biochemistry and function will lead to better strategies to maintain quality of life for Parkinson’s sufferers.