Abstract
Cardiotoxicity from long-term use of the anticancer drug, doxorubicin (DOX), imposes a strict limitation its administration. The health benefits of avocado seeds (AS) stem from essential nutrients and phytochemicals. This study aimed to compare effects of ethanol (EAS), and water (WAS) extracts from AS on DOX-induced cardiotoxicity. Forty adult male albino rats were divided into four groups: GI were control rats. GII rats received DOX alone over a 2 week period. GIII animals received the DOX treatment plus AS. GIV rats received the DOX treatment plus EAS. AS extract treatments were administered after initiation of cardiotoxicity. Total flavonoids, polyphenols, and antioxidant capacity of both AS extracts were measured. Serum markers of cardiac dysfunction were evaluated, oxidative stress and inflammatory biomarkers were measured in cardiac tissue homogenates and histopathology of heart tissues was evaluated. The AS ethanolic extract had a higher content of active compounds. DOX treatment increased markers of cardiac dysfunction Matrix Metalloproteinase-1 (MMP-1), Serum Cardiac Troponin I (cTnI), Lactate Dehydrogenase (LDH), Serum Creatine Kinase Isoenzyme-MB (CK-MB), and Heart-Type Fatty Acid-Binding Protein (FABP3) and produced increases in levels of Advanced Oxidation Protein Products (AOPP) and Malondialdehyde (MDA) in cardiac tissue homogenates with a significant reduction in Catalase (CAT), Total Antioxidant Capacity (TAC). It also increased levels of Tumor Necrosis Factor (TNF-a), Interleukin-6 (IL-6), Interleukin-1 beta (IL-1ss) and Caspase-3, in the cardiac tissue homogenates. EAS was more effective than WAS, but both acted as cardioprotective agents following DOX treatment as evidenced by mitigation of impacts on biochemical markers.