Increase of serum phosphatidylcholine hydroperoxide dependent on glycemic control in type 2 diabetic patients

In order to clarify the relationship between serum phosphatidylcholine hydroperoxide (PCOOH) levels and blood glucose control in type 2 diabetes patients (DM), DM (n=61) and normal control (n=11) were enrolled. High-density lipoprotein (HDL) was separated from serum by the addition of sodium phosphotungstate and magnesium chloride, and the precipitated fraction was prepared as non-HDL. Phospholipids were extracted from whole serum, non-HDL and HDL to estimate PCOOH level with chemiluminescence high performance liquid chromatography (CL-HPLC). PCOOH level (nmol/l, mean±S.D.) was higher in DM than in control (33.1±9.5 vs. 23.0±8.2 for serum; P<0.01, 17.0±5.5 vs. 10.6±3.8 for non-HDL; P<0.01, and 16.1±6.3 vs. 12.3±5.5 for HDL; not significant, respectively). DM was divided into five groups according to hemoglobin A1c (HbA1c) levels (%): (1) less than 6, (2) 6–6.4, (3) 6.5–6.9 (4) 7.0–7.4, and (5) over than 7.5. Increase of PCOOH levels was dependent on HbA1c. We concluded that (1) serum and non-HDL PCOOH increased in DM, (2) the level was strongly correlated with diabetic control, and (3) approximately a half amount of serum PCOOH was present in HDL of both control and DM. [Copyright &y& Elsevier]