SUPPLEMENTATION WITH ANTIOXIDANTS PRIOR TO BONE-MARROW TRANSPLANTATION

Conditioning therapy preceding bone marrow transplantation (BMT) usual ly consists of high-dose chemotherapy and total body irradiation (TBI) . It has acute and delayed toxic effects on several tissues, possibly related to peroxidation processes and exhaustion of antioxidants. Earl y studies indicated an increase of peroxide processes and a decrease o f antioxidants during conditioning therapy. Hence, we investigated the effect of antioxidant supplementation on peroxidation processes and a ntioxidant status. We supplemented a patient group (N = 16) [BMT (+)] with oral 45 mg beta-carotene, 825 mg alpha-tocopherol and 450 mg asco rbic acid daily for three weeks before conditioning therapy. Another p atient group (N = 10), BMT(-), was not supplemented with antioxidants before conditioning therapy. In order to investigate the physiologic e ffect of supplement antioxidants a healthy control group (N = 10) was supplemented with the same doses as BMT(+). Peroxide concentrations in plasma were measured by using the cholesterol oxidase (CHOD)-iodide m ethod and antioxidants were measured by HPLC. Before supplementation t he beta-carotene and a tocopherol concentrations were comparable in bo th patient groups. After supplementation significantly higher beta-car otene and alpha-tocopherol concentrations were measured in the supplem ented patients, BMT(+), than in the unsupplemented patients, BMT(-). A fter conditioning therapy, BMT(+) patients showed a significantly high er beta-carotene concentration (p < 0.05) than before supplementation. In BMT(-) patients the beta-carotene (p < 0.05) and alpha-tocopherol concentrations (p < 0.01) decreased significantly and the lipid peroxi de concentration increased significantly following conditioning therap y. We conclude that antioxidant supplementation prior to conditioning therapy reduces peroxidation processes induced by conditioning therapy in bone marrow recipients.