Decreased concentrations of serum phospholipid plasmalogens indicate oxidative burden of uraemic patients undergoing haemodialysis.

Experimental evidence indicates that uraemic patients undergoing haemodialysis are subject to increased oxidative stress. Plasmalogens are a phospholipid subclass found in cell membranes and plasma lipoproteins, which may work as an endogenous antioxidant. Using gas chromatography, we measured reduced portions of fatty aldehyde dimethyl acetals (16:0 DMA and 18:0 DMA, representing derivatives of plasmalogens) in fatty acid patterns of fasting serum phospholipids from 30 patients with chronic renal failure (CRF) receiving repeated ambulatory haemodialysis, as compared to 99 normal control subjects (CS). The highly significant difference of mean 16:0 DMA and 18:0 DMA values between CRF patients and CS (0.53 +/- 0.15 vs. 0.67 +/- 0.13, p < 0.001 and 0.33 +/- 0.11 vs. 0.40 +/- 0.11, p < 0.01, respectively) was lost when the patients were compared to subjects older than 85 (16:0 DMA) or 75 years (18:0 DMA). Weak, but significant inverse correlations with age or triglycerides were observed in blood serum of CS for 16:0 DMA and 18:0 DMA, respectively, but not of the patients. Partial correlation analysis indicated a mutually independent association of age and triglyceride values with serum plasmalogens in CS, but not in CRF patients. In conclusion, the reduced content of serum plasmalogen phospholipids of uraemic patients undergoing haemodialysis suggests an increased oxidative stress.