This review article by Rozycka et al (2014) discusses the harmful effects elevated homocysteine (Hcy) levels can play on diseases affecting brain function such as Alzheimer’s and Parkinson’s Disease. This is due to evidence demonstrating High Hcy to have a toxic effect upon the brain, contributing to degeneration of brain tissue through oxidative damage, cell death, calcium accumulation and excessive stimulation.
High Hcy can in part reflect nutritional deficiencies involved in the methylation pathway, being B12, folate and B6. Genetic polymorphisms involved in folate metabolism (such as MTHFR C677T & A1298C) have be found to be generally increased in patients with Parkinson’s Disease, as well as reduced concentrations of B vitamins. Increased levels of Hcy in Parkinson’s disease could potentially lead to dementia, depression and progression of the disease.
While this article highlights the effect of homocysteine on brain function, it also highlights the importance of sufficient nutrition to allow our methylation cycles to function sufficiently. This ensures our brain tissue is not damaged by high homocysteine.