Pomegranate fruit peel extract improves cardiac functions via suppressing oxidative stress, fibrosis, and myocardial infarction in Long-Evans rats

The pomegranate fruit (locally known as Dalim) is a rich source of various bioactive metabolites. This study aimed to investigate the cardioprotective effect of polyphenol-rich pomegranate peel extract (PPE) in isoproterenol, a synthetic catecholamine-induced cardiac stress in rats. Twenty-four adult rats were taken to evaluate the effects. The selected rats were divided into four groups, such as control (Group I), Isoproterenol (ISO) administered (Group II), PPE with ISO treatment (Group III), and gallic acid (polyphenol) along with ISO administration (Group IV). As expected, ISO administration increased inflammatory cell infiltration, fibrosis, and lipid peroxidation. However, antioxidant enzyme activities were reduced in heart tissues of ISO-treated rats. Interestingly, PPE treatment effectively reduced ISO-induced various detrimental effects in heart tissues in rats. This protection was associated with several positive outcomes, including reduced inflammatory cell infiltration and fibrosis, reduction in free radicals by improving antioxidant enzymes activities, suppression of oxidative stress markers, and reduction in inflammatory marker. Besides, PPE treatment normalized the elevated levels of liver and cardiac injury markers. The cardioprotective effects shown by PPE may be due to the presence of polyphenolic compounds, as determined by HPLC analysis. Overall, these data suggest that polyphenol enriched PPE may protect cardiac tissues in ISO-administered rats by suppressing oxidative stress, fibrosis, and myocardial infarction as well as enhancing antioxidant enzymes.