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Increased homocysteine and decreased adenosine formation in Alzheimer's disease

Michael L Selley1

  • 1Angiogen Pharmaceuticals Pty. Ltd, Sydney, N.S.W., Australia. mlselley@angiogen.com.au

Neurological Research
|July 22, 2004
PubMed

Insights

Elevated homocysteine levels in Alzheimer's disease patients correlate with decreased adenosine, a protective molecule. This suggests a potential mechanism linking vascular factors, homocysteine, and Alzheimer's pathology.

Area of Science:

  • Neuroscience
  • Biochemistry
  • Vascular Biology

Background:

  • Vascular risk factors are linked to increased Alzheimer's disease (AD) risk.
  • Elevated plasma homocysteine is associated with vascular risk factors and AD, but mechanisms remain unclear.
  • Homocysteine may impair adenosine's protective functions against vascular disorders contributing to AD pathology.

Purpose of the Study:

  • To investigate the relationship between plasma homocysteine and adenosine concentrations in Alzheimer's disease patients.
  • To explore the potential role of adenosine deficiency in the vascular pathology associated with homocysteine in AD.

Main Methods:

  • Plasma homocysteine and adenosine levels were measured in 25 AD patients and 25 age-matched control subjects.
  • Statistical analysis, including correlation studies, was performed to assess the relationship between homocysteine and adenosine concentrations.

Main Results:

  • Alzheimer's disease patients exhibited significantly higher plasma homocysteine concentrations (p < 0.0001).
  • A significant decrease in plasma adenosine concentrations was observed in AD patients (p < 0.001).
  • A strong negative correlation was found between homocysteine and adenosine levels in both combined groups (r = -0.769, p < 0.0001) and the AD group (r = -0.773, p < 0.0001).

Conclusions:

  • Decreased adenosine levels may contribute to the vascular pathology observed in Alzheimer's disease.
  • The inverse relationship between homocysteine and adenosine suggests a potential pathway through which vascular risk factors influence AD pathogenesis.
  • Further research is warranted to elucidate the precise role of adenosine in homocysteine-mediated vascular damage in AD.

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