COMPARATIVE INDUCTION OF OXIDATIVE STRESS IN CULTURED J774A.1 MACROPHAGE CELLS BY CHROMIUM PICOLINATE AND CHROMIUM NICOTINATE

The concentration-dependent effects of chromium picolinate and chromiu m nicotinate were assessed on the enhanced production of reactive oxyg en species including superoxide anion and hydroxyl radicals, and lipid peroxidation and DNA fragmentation in cultured macrophage J774A.1 cel ls. The macrophage cells were incubated with 0 - 50 mg/ml concentratio ns of these chromium (III) salts for 0 and 24 hrs at 37 degrees C. Con centration-dependent effects were observed. Lipid peroxidation increas ed by 1.3 - 1.5-fold following treatment of these cells with chromium picolinate while at these same concentrations of chromium nicotinate a pproximately 1.2 - 1.8-fold increases in lipid peroxidation were obser ved. Increases of 1.0 - 1.5-fold occurred in the production of superox ide anion as determined by cytochrome c reduction following treatment with chromium picolinate while with these same concentrations and cond itions only 1.1 - 1.2-fold increases in cytochrome c reduction were ob served following treatment with chromium nicotinate. Approximately 1.2 - 1.5-fold increases in hydroxyl radical production were observed fol lowing treatment of these macrophage cells with increasing concentrati ons of chromium picolinate and chromium nicotinate. Incubation of the cells with 30 - 50 mu g/ml concentrations of chromium picolinate produ ced 1.2 - 1.6 fold increases in DNA fragmentation, while under these s ame conditions with chromium nicotinate 1.2 - 1.3-fold increases in DN A fragmentation occurred. No significant loss in eel viability was obs erved with either chromium salt. These results demonstrate that incuba tion of macrophage J774A.1 cells with these chromium salts induces low levels of oxidative stress as demonstrated by the biochemical assay t echniques employed in this study.