EFFECT OF MAGNESIUM SUPPLEMENTATIO N ON OXIDATIVE MODIFICATION OF HUMAN LOW DENS ITY LIPOPROTEIN / 营养学报

ABSTRACT

Objective: The effects of magnesium on the oxidation of low density lipoprotein (LDL) were systematically investigated by two different oxidation systems. Methods: LDLs were isolated from pooled healthy human fresh sera by ultracentrifugation. Oxidation of LDL was induced by adding Cu 2+ or co-cultured with cultured human umbilical vein endothelial cells. Conjugate diene was measured to assess the susceptibility of LDL to oxidation. The extent of LDL modification was determined by measuring the formation of thiobarbituric acid reaction substances (TBARS). Results: (1)The presence of Mg 2+ resulted in a protracted lag phase at doses of 0.3 mmol/L, 0.6 mmol/L, 1.2 mmol/L, and 2.4 mmol/L, as well as decreased production of TBARS when LDL was oxidized by the addition of Cu 2+ , at doses of 0.3 mmol/L and 0.6 mmol/L Mg 2+ .(2)Treatment of LDL with Mg 2+ (0.3 mmol/L, 0.6 mmol/L, 1.2 mmol/L, and 2.4 mmol/L) reduced the production of TBARS during endothelial cell-mediated LDL oxidation, P