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Updated: Aug 11, 2026
17:12
Profiling of Methyltransferases and Other S-adenosyl-L-homocysteine-binding Proteins by Capture Compound Mass Spectrometry (CCMS)
Published on: December 20, 2010
Homocysteine remethylation and trans-sulfuration
1Lady Davis Institute for Medical Research, Jewish General Hospital, Montreal, Quebec H3T1E2, Canada.
Metabolism: Clinical and Experimental
|November 13, 2004
Summary
Measuring plasma homocysteine (Hcy) turnover under steady-state conditions limits understanding of hyperhomocysteinemia causes. New methods are needed to accurately determine metabolic blocks and Hcy accumulation.
Area of Science:
- Biochemistry
- Metabolic pathways
- Clinical chemistry
Background:
- Plasma homocysteine (Hcy) concentration reflects the balance of its metabolic processes.
- Hyperhomocysteinemia research often involves measuring plasma Hcy turnover.
- Previous studies were limited by steady-state assumptions.
Purpose of the Study:
- To highlight the limitations of steady-state conditions in studying Hcy metabolism.
- To emphasize the need for improved methods to assess Hcy turnover.
- To clarify confusion in the literature regarding whole-body Hcy metabolism.
Main Methods:
- Review of existing literature on plasma Hcy turnover.
- Analysis of the implications of steady-state versus non-steady-state conditions.
- Discussion of metabolic block identification.
Main Results:
- Steady-state measurements do not accurately reveal the type or severity of metabolic blocks causing metabolite accumulation.
- This limitation has contributed to confusion in understanding whole-body Hcy metabolism.
- Current methods may not fully elucidate the causes of hyperhomocysteinemia.
Conclusions:
- Understanding Hcy metabolism requires moving beyond steady-state assumptions.
- Accurate assessment of Hcy turnover is crucial for diagnosing metabolic disorders.
- Further research into non-steady-state methods is warranted for Hcy metabolism studies.
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