Lipid peroxidation of intravenous lipid emulsions and DNA damage

Objectives:Lipid emulsions used in parenteral nutrition are prone to peroxidation that may be an important feature of oxygen associated tissue damage.In the present study,we determine whether lipid emulsions increase lipid peroxidation in vivo ,and evaluate endogenous oxidative damage to DNA in healthy subjects while receiving intravenous lipid emulsions. Methods:Twenty two healthy subjects were studied on two occasions at an interval of 2 weeks.Intralipid and Vasolipid were infused for 4 hours at a rate of 0.15 g TG/h,blood samples were taken before and during lipid infusion.We used a new colorimetric assay to measure the end products of lipid peroxidation,HPLC was performed to measure plasma concentration of α tocopherol;the urinary concentration of 8 Hydroxyguanine(8 OHGua) was measured by HPLC and isotope dilution mass spectrometry. Results:The plasma MDA and 4 hydroxyalkenal increased significantly after the infusion of lipid emulsions;the infusion lipid emulsions for 4 hours didnt result in a marked changes of plasma α tocopherol and 8 Hydroxyguanine levels. Conclusions:Lipid peroxidation increased after the infusion of lipid emulsions.The infusion lipid emulsions for 4 hours did not result in oxidative DNA damage and didnt influence the plasma α tocopherol levels.