Doxorubicin-induced myocardial failure in rats with malignant neoplasm:: Protective role of fullerenol C60(OH)24

The therapeutic utility of the anthracycline antibiotic doxorubicin is limited due to its cardiotoxicity. Our aim was to investigate the efficacy of fullerenol C-60(OH)(24) in preventing single, high-dose doxorubicin-induced cardiotoxicity in rats with malignant neoplasm. In vitro and in vivo studies have shown that fullerenol C-60(OH)(24), has strong antioxidative potential. Experiment was performed on adult female Sprague Dawley rats with chemically induced mammary carcinomas. All 32 rats (2-5 groups) received i.p. applications of 1-methyl-1-nitrosourea (MNU; 50 mg/kg body weight) on the 50(th) and 113(th) day of age. Animals were randomly divided into five groups as follows: (1) Untreated control group - rats received saline only; (2) Cancer control group - rats received MNU and saline; (3) Dox group - rats received MNU and Dox 8 mg/kg; (4) Full/Dox group rats received MNU and Full 100 mg/kg 30 min before Dox 8 mg/kg; (5) Full group - rats received MNU and Full 100 mg/kg. Tumour incidence was 4.94 +/- 0.576 per rat. The animals were sacrificed 2 days after the application of doxorubicin and/or fullerenol, and the serum activities of CK, LDH and alpha-HBDH, as well as the levels of MDA, GSH, GSSG, GSH-Px, SOD, CAT, GR and TAS in the heart, were determined. The results obtained from the enzymatic activity in the serum show that the administration of a single dose of 8 mg/kg in all treated groups induces statistically significant damage. There are significant changes in the enzymes of LDH and CK (p < 0.05), after an i.p. administration of dexorubicin/fullerenol and fullerenol. Comparing all groups with untreated control group, point to the conclusion that in the case of a lower alpha-HBDH/LDH ratio, results in more serious the liver parenchymal damage. The results revealed that doxorubicin induced oxidative damage and that the fullerenol antioxidative influence caused significant changes in MDA, GSH, GSSG, GSH-Px, SOD, CAT, GR and TAS level in the heart (p < 0.05). Ultra structural analysis of heart tissues from rats treated with doxorubicin and indicated that the hearts of the rats were protected from doxorubicin-induced subcellular damage. Doxorubicin/fullerenol rats did not appear to show significant cardiac damage although occasional focal loss of cristae in the mitochondria was observed. Therefore, it is suggested that fullerenol might be a potential cardioprotector in doxorubicin-treated individuals.