Evaluation of endothelial function and platelet activation in dyslipidemic children

Objective: The aim of this study was to determine the parameters of endothelial function and platelet activation in children with familial hypercholesterolemia by measuring plasma homocysteine, asymmetrical dimethyl arginine (ADMA), nitrotyrosine and P-selectin levels. Methods: Thirty-five heterozygous familial hypercholesterolemic patients on statin therapy, 10 homozygous familial hypercholesterolemic patients treated by LDL apheresis and lipid-lowering drugs, and 25 healthy children, all aged between 2 to 16 years were enrolled in this study. Echocardiography was performed and intima-media thickness (IMT), and endothelium-dependent vasodilation parameters were evaluated. LDL apheresis was performed by adsorption method using double-membrane filtration technique. Plasma nitrotyrosine, homocysteine, P-selectin and ADMA levels were determined with an enzyme-linked immunosorbent assay (ELISA) using a commercial kit. Results: Plasma homocysteine (p=0.000), ADMA (p=0.005), nitrotyrosine (p=0.808), p-selectin (p=0.466) levels were lowest in the LDL apheresis group. A positive correlation was detected between homocysteine and intima/media thickness (r=0.334, p=0.043). Showed that LDL apheresis therapy might decrease plasma levels of homocysteine, ADMA, and nitrotyrosine, and might eventually play an important role in the improvement of endothelial dysfunction and platelet activity. Conclusion: Our data showed that at post-LDL apheresis status the homozygous hyperlipidemic children have lower levels of homocysteine, ADMA, and nitrotyrosine, compared with the heterozygous hyperlipidemic children.