Increased metabolism of peroxynitrite-modified [125I] beta-VLDL by monocytes from hypercholesterolemic rabbits

The metabolism (uptake and degradation) of peroxynitrite-modified beta-VLDL and native beta-VLDL labeled with [125I]iodine was studied in monocytes isolated from peripheral blood of hypercholesterolemic (HC) and normolipidemic rabbits (NC). The peroxynitrite-modified beta-VLDL uptake and degradation was up to 2-fold higher in monocytes from HC rabbits than monocytes from NC rabbits. In addition, monocytes from HC rabbits took up and degraded significantly more peroxynitrite-modified beta-VLDL than native beta-VLDL. In contrast, monocytes from NC rabbits took up both lipoproteins in a similar rate and degraded more native beta-VLDL than peroxynitrite-modified beta-VLDL. Our results suggest that hypercholesterolemia can affect monocyte metabolism enhancing foam cell formation by increasing the influx of peroxynitrite-modified beta-VLDL.