PHARMACOKINETICS OF SUPEROXIDE-DISMUTASE IN RATS AFTER ORAL-ADMINISTRATION

The kinetic behaviour of bovine erythrocyte Cu-Zn SOD was investigated in Sprague Dawley male rats after subcutaneous and oral administratio ns of doses ranging from 0.5 to 20 mg kg(-1). Studies have been carrie d out with SOD and SOD encapsulated into liposomes containing or not c ontaining ceramides. The maximum concentration (C-max) in blood cell p ellets ranged from 8.65 to 11.03 U/mg haemoglobin (Hb) after subcutane ous injection, and from 4.48 to 8.23 U/mg Hb after oral administration . The maximum concentrations were reached in 5 h (t(max)) for the two routes. Comparison between the areas under the curves (AUCs) obtained after subcutaneous and oral administration allowed the calculation of relative bioavailability (F'). The maximum bioavailability after oral administration was 14% for free SOD, 22% for SOD encapsulated into lip osomes, and 57% when ceramides were added to liposomes. Poor SOD bioav ailability was enhanced by liposome encapsulation, and ceramide additi on seemed to be beneficial for oral encapsulated SOD administration.