Erythropoietin supplement increases plasma lipoprotein lipase and hepatic triglyceride lipase levels in hemodialysis patients

Abstract

We reported in previous studies that plasma triglyceride levels, as well as remnant-like particles-cholesterol (RLP-C) and -triglyceride (RLP-TG) levels, were significantly lower in maintenance hemodialysis (HD) patients treated with erythropoietin (EPO) than in HD patients treated without EPO. However, little is known about the mechanisms underlying the improvements in abnormal RLP metabolism in HD patients. This study investigates whether EPO supplement therapy in cases of uremic anemia increases the plasma lipoprotein lipase (LPL) and hepatic triglyceride lipase (HTGL) levels in HD patients. Twenty HD patients who had not previously received EPO were divided into two groups according to the stage of HD: 12 at the initial stage, defined as a mean HD duration of 0.35 +/- 0.68 months (range of 0 to 2.47 months), and 8 at the maintenance stage, defined as a mean HD duration of 114.1 +/- 91.9 months (range of 13.0 to 253.9 months). Fasting plasma was collected from the HD patients prior to the start of the EPO supplement therapy and at one month after the therapy. RLP-C levels were determined using a RLP-C JIMRO II kit. Fasting plasma was also collected from the HD patients 10 minutes after an intravenous injection of heparin (30 U/kg body wt). Plasma LPL levels were determined using an enzyme immunoassay, and HTGL levels were determined using a modified version of the Hernell et al method. Plasma RLP-C levels showed a tendency to decrease after the start of the EPO supplement therapy in HD patients at the maintenance stage. Plasma LPL levels were significantly higher in the two groups of HD patients one month after the start of the EPO supplement therapy than in the same patients prior to the start of the EPO supplement therapy. Plasma HTGL levels were significantly higher in HD patients at the maintenance stage one month after the start of the EPO supplement therapy than in HD patients at the maintenance stage prior to the start of the EPO supplement therapy. The results of this study suggest that the EPO supplement therapy may reduce plasma RLP-C levels by increasing the plasma LPL and HTGL levels in maintenance-stage HD patients.