Peptide compounds and methods for upregulating expression of a gene encodingan antioxidative enzyme, such as superoxide dismutase or catalase, tocounteract harmful oxidative effects of reactive oxygen species and other freeradicals are described. The peptide compounds may be used to treat or preventdiseases and conditions characterized by undesirable elevation of reactiveoxygen species and other free radicals, to upregulate AP-1 gene expression,and to treat pain. The peptide compounds may be used as components ofpharmaceuticals and dietary supplements.