THE EFFECT OF GLUTATHIONE IN CHINESE HAMSTER OVARY CELLS WHEN TREATED WITH CHROMIUM AND NICKEL

Abstract

Glutathione is a well-known antioxidant, present in all mammalian cells as the most abundant nonprotein thiol defending against oxidative stress, as a result it can protect DNA damage caused by reactive oxygen species. In This study we investigated the possible protective effect(s) of Glutathione against Nickel (Ni II) and Chromium (Cr VI) toxicity. Chinese Hamster Ovary cells (CHO) were treated with various concentrations of Ni (II) {1uM, 5uM, 10uM, 25uM} and Cr (VI) {0.5uM, 1uM, 2.5uM, 5uM}, alone. Furthermore, we treated cells with Ni (II) {1uM, 5uM, 10uM, 25uM} combined with glutathione {0.006M, 0.01M, 0.02M} as well as, Cr (VI) {0.5uM, 1uM, 2.5uM, 5uM} with glutathione {0.006M, 0.01M, 0.02M}. The Cell viability was assessed by the Trypan blue assay. Our results indicate that cell viability decreases as the metal concentration was increased. Specifically, as the concentration of Ni (II) and Cr (VI) increases, the cell viability for both metals decreased in a dose dependent fashion. For the combined treatments of both the metals with glutathione, we observed that cell viability increased when the cells were treated with 5uM, 10uM, 25uM of Ni (II) and 0.01M glutathione as well as 1uM,2.5uM, 5uM of Cr (VI) and 0.01M glutathione, indicating that glutathione had a protective effect against Ni (II) or Cr (VI) toxicity. No protective effect was seen at lower concentration (0.006M) of glutathione treatments. However, at higher levels of glutathione (0.02M) the cell viability decreased, indicating a toxic effect of glutathione. Therefore, caution should be exercised when glutathione is used as a dietary supplement.