Disturbed LDL and scavenger receptor functions in monocytes from chronic haemodialysed patients

Background. The most frequent complication in patients with end-stage renal failure on chronic haemodialysis (HD) treatment is atherosclerosis, i.e. t he different forms of heart and vascular diseases. The complete disorder of serum lipid and lipoprotein patterns is well demonstrated, whereas our kno wledge about the low-density lipoprotein(LDL) and scavenger receptor expres sion and function are poorly understood. Methods. In our current work, LDL and scavenger receptor expression and fun ctions were simultaneously studied in monocytes obtained from 15 healthy ma le control subjects and from I I chronic HD male patients applied with I-12 5-labelled LDL, isolated from healthy volunteers. To study the scavenger LD L receptors, labelled acetylated LDL (acLDL) was used. Results. LDL binding to the monocytes of the HD-group was found to be decre ased in comparison to that of the controls. As a result, the 50 mu g LDL pr otein-induced inhibition of endogenous cholesterol synthesis was also dimin ished. In contrast, acLDL binding was greatly increased, though it could tr igger only a low apoE synthesis. Consequently the number of cholesterol inc lusions in monocytes was increased. Conclusions. The disturbed expression and function of LDL and scavenger rec eptors both may play significant roles in pathogenesis of cardiovascular co mplications in chronic HD patients. Based on our present results, it can be assumed that dysfunction of scavenger receptors is at the centre of cardio vascular complications of HD patients with renal failure.