Plasmalogens in Human Serum Positively Correlate with High- Density Lipoprotein and Decrease with Aging

Abstract

Aim:The objective of the present study was to propose plasmalogens as a beneficial factor in human plasma by showing a highly positive correlation with high-density lipoprotein (HDL) and a significant reduction with aging. Methods: For 148 elderly subjects suspected of coronary artery disease (CAD), clinical characteristics such as coronary stenosis, hyperlipidemia, abnormal glucose tolerance, and hypertension were investigated, and serum biochemical markers including plasmalogens were determined. Results: Serum plasmalogens levels tended to fall in significant coronary stenosis and abnormal glucose tolerance. Correlative analyses among serum biochemical markers revealed that plasmalogens positively correlate with HDL-related values, particularly apolipoprotein A-(apo A-), and that the molar ratio of choline plasmalogen (ChoPlas) to ethanolamine plasmalogen (EtnPlas) correlates positively with low-density lipoprotein (LDL) particle size, and negatively with apo A-and fasting triglyceride (TG) levels. Comparison of plasmalogens in elderly subjects with those of 119 healthy young subjects showed a marked decrease in serum plasmalogens levels by aging. Conclusion: These results suggest that serum plasmalogens, antioxidant phospholipids, function as a beneficial factor as well as HDL, and that the measurement of serum plasmalogens is useful in clinical diagnosis.

Improvement and validation of 125I-high-performance liquid chromatography method for determination of total human serum choline and ethanolamine plasmalogens

“…13 Quantification of Pls is carried out by measuring the decrease in the absorbance at 355-360 nm, which reflects the extent of eliminated triiodide (1-) ion (I 3 2 ) due to the reaction with a vinyl-ether double bond of Pls. We confirmed that the reaction molar ratio of I 3 2 to vinyl-ether bond is exactly 1:1, using several chemical compounds possessing a vinyl-ether bond as well as Pls.…”

“…After addition of 2.2 mL ethanol to the mixture, the absorbance of the mixture was measured with a spectrophotometer (V-530; Jasco Co Ltd, Tokyo, Japan) at wavelength 355 -360 nm. A decrease in the absorbance of Pls samples compared with that of blank samples accurately reflects the amounts of Pls because of the equivalent reaction molar ratio of I 3 2 to vinyl-ether double bond of Pls.…”

“…Ether fraction including 1-alkenyl 2,3-cyclic glycerophosphate (upper layer) was collected by centrifugation at 1000g for 15 min, and recovered by additional diethyl ether (3.0 mL) and centrifugation again. The collective ether fractions were evaporated under N 2 gas, re-dissolved in CHCl 3 and stored at 2208C until use ( Figure 1). The recovery rate of 1-alkenyl 2,3-cyclic glycerophosphate corresponded to approximately 70% of LyPlsCho, added in the reaction mixture.…”

“…These diseases are often substantially deficient in Pls, because part of Pls' biosynthetic enzymes are localized in this organelle. 2 Recently, serum (or plasma) Pls have gained interest in several clinical symptoms such as metabolic syndrome/atherosclerosis 3,4 or Alzheimer's disease 5 other than peroxisomal disorders.…”

Serum Choline Plasmalogen is a Reliable Biomarker for Atherogenic Status

“…Interestingly, in addition to the strong correlation of PlsCho with HDL (Maeba et al, 2007), LDL particle size significantly correlated with PlsCho/PlsEtn ratio as well as TG and HDL-C (Table 6). Small dense LDL (sdLDL) is well-known risk factor for atherosclerosis, and frequently observed in dyslipidemia of type-2 diabetes or MetS, which is characterized by low HDL and high TG (Nozue et al, 2007 TC, mg/dl 189 ± 40 apo B-48, mg/dl 6.9 ± 3.2 LDL-C, mg/dl 119 ± 45 apo C-II, mg/dl 4 ± 2 HDL-C, mg/dl 47 ± 11 apo C-III, mg/dl 9 ± 3 RLP-C, mg/dl 5 ± 2 apo E, mg/dl 4.3 ± 1.3…”