Diurnal variation in lipoprotein-associated phospholipase A(2) (Lp-PLA(2))
Leonard A Kaminsky1, Cemal Ozemek
1Ball State University, Human Performance Laboratory, Clinical Exercise Physiology Program, Muncie, IN 47306, USA. kaminskyla@bsu.edu
Clinical Biochemistry
|April 3, 2012
Summary
Lipoprotein-associated phospholipase A(2) (Lp-PLA(2)) shows minimal diurnal variation in mass and activity. This suggests that serial measurements of Lp-PLA(2) do not require strict timing for accurate cardiovascular risk assessment.
Area of Science:
- Biochemistry
- Cardiovascular Medicine
- Clinical Chemistry
Background:
- Lipoprotein-associated phospholipase A(2) (Lp-PLA(2)) is an arterial enzyme linked to vulnerable plaque formation and cardiovascular disease (CVD) risk.
- Understanding the diurnal variation of Lp-PLA(2) is crucial for accurate risk assessment, but this has not been previously established.
Purpose of the Study:
- To investigate the diurnal variation in both Lp-PLA(2) mass and activity.
- To determine if Lp-PLA(2) levels fluctuate significantly throughout a 24-hour period.
Main Methods:
- Blood samples were collected from 18 participants (10 men, 8 women; age 22-76) every 4 hours over 24 hours.
- Lp-PLA(2) mass and activity were measured in each sample.
- Coefficients of variation (CV) were calculated to assess variability.
Main Results:
- The mean CV for Lp-PLA(2) mass was 5.9% (range 2.5-9.4%).
- The mean CV for Lp-PLA(2) activity was 3.7% (range 1.2-6.8%).
- No significant correlations were found between CV and subject characteristics.
Conclusions:
- Diurnal variation of Lp-PLA(2) mass and activity is comparable to established lipoprotein risk factors.
- The low diurnal variability indicates that serial Lp-PLA(2) measurements do not need to be taken at the same time of day.
- This finding simplifies clinical monitoring and risk assessment for cardiovascular disease.
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