Homocysteine and brain atrophy

Perminder S Sachdev1

  • 1School of Psychiatry, University of New South Wales, Sydney NSW 2052, Australia. p.sachdev@unsw.edu.au

Insights

High homocysteine (Hcy) is linked to brain atrophy and neurodegenerative diseases like Alzheimer's. Further intervention studies are needed to confirm its role and explore potential treatments for these conditions.

Area of Science:

  • Neuroscience
  • Biochemistry
  • Vascular Biology

Background:

  • Homocysteine (Hcy) is associated with vascular disease and brain atrophy.
  • Mechanisms include oxidative stress, DNA damage, apoptosis, excitotoxicity, and vascular wall damage.
  • Hcy is prothrombotic and proatherogenic.

Purpose of the Study:

  • To review the role of homocysteine in neurodegeneration and brain atrophy.
  • To explore the association of Hcy with cognitive impairment, Alzheimer's Disease (AD), and Parkinson Disease (PD).
  • To highlight the potential of Hcy as a target for intervention in degenerative brain disorders.

Main Methods:

  • Literature review of epidemiological and longitudinal data.
  • Analysis of proposed mechanisms linking Hcy to neurodegeneration.
  • Discussion of Hcy's role in alcohol-related brain atrophy.

Main Results:

  • Hcy is implicated in brain atrophy, particularly in older individuals, and potentially white matter hyperintensities (WMH).
  • Epidemiological data support Hcy as a risk factor for cognitive impairment and AD, possibly via cerebrovascular and neurotoxic pathways.
  • The role of Hcy in PD is less established, but it may mediate alcohol-related brain atrophy.

Conclusions:

  • High homocysteine is a significant risk factor for vascular disease and neurodegeneration.
  • Its prevalence and treatability make it a promising target for future intervention studies.
  • Further intervention studies are crucial to confirm Hcy's etiological role in degenerative brain disorders.

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