ABSTRACT
BACKGROUND: Chemotherapy-induced left ventricular dysfunction represents a major clinical problem, which is often only recognised at an advanced stage, when supportive therapy is ineffective. Although an early heart failure treatment could positively influence the health status and clinical outcome, there is still no evidence of routine prophylactic cardioprotection for the majority of patients without previous cardiovascular history awaiting potentially cardiotoxic chemotherapy. In this study, we set out to investigate whether a prophylactic cardioprotective therapy relative to a conventionally scheduled heart failure treatment is more effective in preventing cardiotoxicity in a rodent model of doxorubicin (DOX)-induced cardiomyopathy. METHODS: Male Wistar rats (n = 7-11 per group) were divided into 4 subgroups, namely negative controls receiving intravenous saline (CON), positive controls receiving intravenous DOX (6 cycles; D-CON), and DOX-treated animals receiving either prophylactic (PRE, started 1 week before DOX) or conventionally applied (POST, started 1 month after DOX) combined heart failure therapy of oral bisoprolol, perindopril and eplerenone. Blood pressure, heart rate, body weight and echocardiographic parameters were monitored in vivo, whereas myocardial fibrosis, capillarisation, ultrastructure, myofilament function, apoptosis, oxidative stress and mitochondrial biogenesis were studied in vitro. RESULTS: The survival rate in the PRE group was significantly improved compared to D-CON (p = 0.0207). DOX increased the heart rate of the animals (p = 0.0193), while the blood pressure (p ≤ 0.0105) and heart rate (p = 0.0029) were significantly reduced in the PRE group compared to D-CON and POST. The ejection fraction remained preserved in the PRE group compared to D-CON or POST (p ≤ 0.0237), while none of the treatments could prevent the DOX-induced increase in the isovolumetric relaxation time. DOX decreased the rate of the actin-myosin cross-bridge cycle, irrespective of any treatment applied (p ≤ 0.0433). The myocardium of the D-CON and POST animals displayed pronounced ultrastructural damage, which was not apparent in the PRE group (p ≤ 0.033). While the DOX-induced apoptotic activity could be reduced in both the PRE and POST groups (p ≤ 0.0433), no treatment was able to prevent fibrotic remodelling or the disturbed mitochondrial biogenesis. CONCLUSION: For attenuating DOX-induced adverse myocardial effects, prophylactic cardioprotection has many advantages compared to a late-applied treatment.
Subject(s)
Cardiomyopathies/chemically induced , Cardiomyopathies/therapy , Doxorubicin/adverse effects , Heart Failure/therapy , Animals , Apoptosis , Cardiomyopathies/diagnostic imaging , Caspase 3/metabolism , Disease Models, Animal , Echocardiography , Fibrosis , Heart Failure/diagnostic imaging , Male , Myocardium/pathology , Myocardium/ultrastructure , Myocytes, Cardiac/metabolism , Myocytes, Cardiac/pathology , Rats, Wistar , Survival AnalysisABSTRACT
Fabry disease is an X chromosome linked disorder caused by the inherited deficiency of lysosomal enzyme α- galactosidase A. The deficiency results in abnormal degradation of certain glycosphingolipids. Although the disease is known for more than hundred years and the underlying molecular basis is getting to be well defined, there are still a lot of unanswered questions regarding the different clinical presentations, available diagnostic procedures and therapeutic interventions. The scope of the article is to review the molecular basis of Fabry disease and summarize the available data about Fabry disease cardiomyopathy, highlight the controversies of current knowledge and evaluate future research directions.
