Oxidative response of rat lung tissue after crown ethers exposure and the effects of alpha-tocopherol treatment

BackgroundIonophoric properties of crown ethers enable them ideally to transport across membranes and interfere with different living systems. We studied cytotoxicity effects of 18-crown-6 and 15-crown-5 and the role of oxidative stress in rat lung tissue culture.MethodsWe assayed the effects of these crown ethers in a range of doses (0.1 to 2 mmol/l) on lipids and proteins oxidative damages end products; malondialdehyde (MDA) and dityrosine and on the activity of antioxidant enzymes; superoxide dismutase (SOD), glutathione peroxidase (GPX), catalase (CAT), in rat lung tissue culture by spectrometry and HPLC.ResultsBoth compounds significantly increased the levels of MDA, dityrosine and enzyme activities at doses > 0.5 mmol/l after 48-h incubation in the lung tissue, representing promotion of ROS generation with respect to control. These effects were more considerable for 18-crown-6 than 15-crown-5. Treatment of lung tissue with 30 μm of α-tocopherol in addition to 2 mmol/l of crown ethers showed significant decrease on the levels of enzyme activities, MDA and dityrosine.ConclusionWe showed the oxidative radicals forming ability of crown ethers as documented in their toxicity effects through lipid and proteins oxidation damages.