Influence of dietary-induced copper and manganese deficiency on ozone-induced changes in lung and liver antioxidant systems

The influence of an animal's copper (Cu) and manganese (Mn) status on its response to ozone was investigated in weanling mice. Control, Cu-deficient and Mn-deficient mice were exposed continuously to 1.2 ppm O₃ or filtered air for 7 days. In control mice, ozone exposure resulted in higher lung activities of CuZnSOD, MnSOD and GPx. In contrast, Mn-deficient mice did not display increases in lung MnSOD, CuZnSOD or GPx activities following ozone exposure. Similarly, ozone-induced increases in lung CuZn-SOD and MnSOD activities were not observed in Cu-deficient mice, although lung GPx activity was increased in these mice relative to their air-breathing controls. These results show that an animal's Cu and Mn status can influence its response to ozone, and the data suggest that Cu- and Mn-deprived animals may be more susceptible to long-term or repetitive ozone exposure.