Troponin-T and brain natriuretic peptide as predictors for adriamycin-induced cardiomyopathy in rats.

BACKGROUND: Clinical methods for the early detection of doxorubicine (adriamycin; ADR) -induced cardiotoxicity have not been established. This study prospectively investigated whether atrial natriuretic peptide (ANP), brain natriuretic peptide (BNP) and cardiac troponin T (TnT) are predictors for ADR-induced cardiotoxicity, and examined the correlations between the serum concentrations of these biomarkers and the functional alternations associated with ADR-induced myocardial damage. METHODS AND RESULTS: Male Wistar rats were injected weekly with 2 mg/kg of ADR via the tail vein for 8 weeks to induce cardiotoxicity. Echocardiograms of each ether anesthetized rat were taken at 6, 8, 10 and 12 weeks after the first administration of ADR, and blood samples collected from the tail vein were used to quantify plasma ANP and BNP, and serum TnT after echocardiography. Plasma BNP and serum TnT significantly increased from 6 to 12 weeks (81.5 to 173.3 pg/ml (p<0.001), <0.01 to 1.09 ng/ml (p<0.05), respectively) with deterioration of left ventricular % fractional shortening (%FS) (58.6% to 36.8%). The %FS significantly correlated with TnT (r=-0.51, p<0.001) and BNP (r=-0.75, p<0.0001); however, the increase of TnT was antecedent to the increase of BNP and the deterioration of %FS. CONCLUSION: Plasma BNP and serum TnT concentrations, especially TnT, measured by this highly sensitive method are useful predictors for ADR-induced cardiomyopathy.

Apoptosis in young rats with adriamycin-induced cardiomyopathy--comparison with pirarubicin, a new anthracycline derivative.

In a previous study, we demonstrated that apoptosis in rats with adriamycin (ADR)-induced cardiomyopathy occurred through a Fas-dependent pathway. Pirarubicin, a new anthracycline derivative, seems to have a lower cardiotoxicity than ADR. To investigate whether pirarubicin has a lower chronic cardiotoxicity compared with ADR, ADR or pirarubicin were injected weekly for 8 wk into young Wister rats via the tail vein. To block the Fas-Fas ligand interaction, an anti-Fas ligand antibody (FasL) was injected with ADR 7, 8, and 9 wk after first administration of ADR. In the control group, saline was injected instead of ADR. ADR significantly induced apoptosis and left ventricular dysfunction 10 wk after the first administration of ADR. Pirarubicin also induced apoptosis, however, its apoptosis was significantly (p = 0.0069) less than that induced by ADR. Fas antigen was overexpressed in the hearts of ADR and ADR+FasL groups, however, an expression of Fas antigen in the pirarubicin group was similar to the expression of Fas antigen in the control group. Thus, pirarubicin has a significantly lower chronic cardiotoxicity compared with ADR.