The invention provides a method for reducing oxidative damage in a mammal, a removed organ, or a cell in need thereof. The method comprises administering an effective amount of an aromatic cationic peptide. The aromatic cationic peptide has (a) at least one net positive charge； (b) a minimum of three amino acids； (c) a maximum of about twenty amino acids, (d) a relationship between the minimum number of net positive charges (pm) and the total number of amino acid residues (r) wherein 3 pm is the largest number that is less than or equal to r+1； (e) a relationship between the minimum number of aromatic groups (a) and the total number of net positive charges (pt) wherein 3a or 2a is the largest number that is less than or equal to pt+1, except that when a is 1, pt may also be 1； and (f) at least one tyrosine or tryptophan amino acid.
