Abstract: Objective To observe the effect of uremic serum on the production of reactive oxygen species (ROS) and interleukin-6 (IL-6) in human umbilical vein endothelial cells (HUVEC), and its intervention by L-carnitine (L-CN). Methods Uremic sera mixed with various concentrations of L-CN (0, 25, 250, 1000 and 2500μM) were added to the culture medium. Semi-quantitative RT-PCR and ELISA were applied to evaluate the expression of IL-6. Cells labeled with oxidation-susceptible fluorescent probe 2,7-dichorofluoresin diacetate(DCFH) and measured by spectrofluorophotometer were used for ROS assay.Results IL-6 and ROS were increased in HUVEC in the presence of uremic serum. With the addition of L-CN (250μM～2500μM) in culture medium, the production of ROS and IL-6 in HUVEC was inhibited, and the inhibition was L-CN concentration dependent. Conclusion Uremic serum induces the micro-inflammation processes of blood vessel endothelia. L-CN inhibits the production of ROS and IL-6 in HUVEC and thus the microinflammation and atherosclerosis processes in uremic patients.

Key words: IL-6, Reactive oxygen species, L-carnitine, Uremia