Keywords: mesoscopic studies, toxic effects, cardiac muscle, doxorubicin, DOX, ultrastructure, mitochondria, cristea, thick myosin filament, anti-tumour agents, human malignancies, nanotechnology, cardiomyocytes, anticancer drugs, cancer, tumours
Mesoscopic studies on toxic effect of doxorubicin on rat cardiac muscles
The anthracycline antibiotic doxorubicin (DOX) is one of the most effective anti-tumour agents used to treat human malignancies. Long-term treatment with DOX is limited by its cardiotoxicity. The purpose of the present study was to evaluate the cardiotoxic effect of DOX using nanoscale. Twelve adult male rats were divided into two groups: control group, group 2A, DOX one week (DOX 1wk), group2B, DOX two weeks (DOX 2wk). Ultrastructural damage using mesoscopic studies showed cardiomyocytes injury after one week and more pronounced after two weeks by increase in thickness of thick myosin filaments (22 nm to 25 nm) and widening of interfilaments spaces (4 nm to 8 nm). In addition to the changes in the mitochondria being the most extensively and progressively injured organelle such as swelling, disorganisation of cristae, vacuolisation to degeneration and complete loss of mitochondrial cristae. The thickness of cristae measured by mesoscopic scale range from 25 nm to 31 nm and spaces vary between 22 nm to 28 nm especially after two weeks of DOX injection.