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

Background. 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) p atients treated with erythropoietin (EPO) than in HD patients treated witho ut EPO. However, little is known about the mechanisms underlying the improv ements in abnormal RLP metabolism in HD patients. This study investigates w hether EPO supplement therapy in cases of uremic anemia increases the plasm a lipoprotein lipase (LPL) and hepatic triglyceride lipase (HTGL) levels in HD patients. Methods. Twenty HD patients who had not previously received EPO were divide d into two groups according to the stage of HD: 12 at the initial stage, de fined as a mean HD duration of 0.35 +/- 0.68 months (range of 0 to 2.47 mon ths), 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 colle cted 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 RL P-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). Plasm a LPL levels were determined using an enzyme immunoassay, and HTGL levels w ere determined using a modified version of the Hernell et al method. Results. Plasma RLP-C levels showed a tendency to decrease after the start of the EPO supplement therapy in HD patients at the maintenance stage. Plas ma LPL levels were significantly higher in the two groups of HD patients on e month after the start of the EPO supplement therapy than in the same pati ents prior to the start of the EPO supplement therapy. Plasma HTGL levels w ere 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 ma intenance stage prior to the start of the EPO supplement therapy. Conclusions. The results of this study suggest that the EPO supplement ther apy map reduce plasma RLP-C levels by increasing the plasma LPL and HTGL le vels in maintenance-stage HD patients.