The protective and therapeutic effects of agmatine on isoproterenol-induced myocardial injury in rats

Chronic inflammation and oxidative stress can contribute to the development of cardiovascular diseases. Isoproterenol (ISO), a synthetic catecholamine, is used to study the effects of drugs on cardiotoxicity. Agmatine (AGM) is a type of biogenic amine produced through the decarboxylation of arginine. The purpose of the current study was to evaluate the effects of AGM against ISO-induced cardiotoxicity due to the described roles of AGM in cardiovascular disease. Four groups of thirty-two Wistar Albino rats were divided equally as control, ISO, AGM+ISO, and ISO+AGM. ISO was administered intraperitoneally (i.p.) twice at a dose of 150 mg/kg, at 24-hour intervals. Prior to and after ISO injection, 20 mg/kg of AGM was injected i.p. Hemodynamic measurements and serum and tissue biochemical analyses were evaluated at the end of the experiment. The levels of glutathione (GSH), catalase (CAT), superoxide dismutase (SOD), and malondialdehyde (MDA) in the tissue were measured. In the ISO group, levels of lactate dehydrogenase (LDH) and creatine kinase (CK) were increased significantly (p<0.05). Co-administration of ISO and AGM significantly reduced CK and LDH levels (p<0.05). MDA levels increased in the ISO-treated group but decreased in the AGM-treated groups (p<0.05). Notably, there was a reduction in the CAT level in the ISO treatment group (p<0.05). CAT was found to be significantly increased (p<0.05) in the groups that received AGM compared to the ISO group. AGM+ISO group had a reduced density of degenerated cardiomyocytes and granulation tissue compared to the ISO group (p<0.05). Although granulation tissue demonstrated a significant reduction in the ISO+AGM group in comparison to the ISO group (p<0.05). In this study, the results indicate that AGM treatment can potentially inhibit ISO-induced myocardial injury and vascular dysfunction by preserving vascular integrity. Notably, the protective effects of AGM on cardiac damage appear to outweigh its therapeutic benefits, as shown by histopathological analysis