The Protective Effect of Ethanolic Extract of Olive Leaf on Aluminum Phosphide-Induced Cardiac Toxicity in Rats

Background: The purpose of this study is to evaluate a treatment for aluminum phosphide (ALP) poisoning, which is known as “rice tablet”. Methods: In the present study, the impact of different doses of ethanolic extract of olive leaves (100, 200, and 400 mg/kg) on ALP (120 mg/kg)-induced cardiotoxicity was evaluated in anesthetized-gastrotomized adult male Wistar rats. Thirty-five rats were randomly assigned into five groups (n=7) as follows: control (AC) and treatment groups [ALP+Olea100 (AO100), ALP+Olea 200 (AO200), and ALP+Olea 400 (AO400)]. Physiological data including blood pressure, heart rate, electrocardiogram (ECG), as well as oxidative stress markers were measured in heart tissues. Results: ALP-intoxication led to perturbed normal ECG and increased oxidative stress. Administration of olive leaf extract at various concentrations, however, mitigated bradycardia after 90 minutes, following ALP-intoxication (in AO200), hypotension (in AO100), and cardiac conduction disturbances (decreased QTC in the AO200 30 (P 0.05), 60 (P 0.001), and 90 (P 0.05) minutes after intoxication) and decreased PR 60 (P 0.05) and 90 minutes (P 0.01) after intoxication. This was compared with baseline as well as detrimental changes in cardiac electrophysiology [mitigated ST-segment elevation in AO200 and depressed T-wave in the AO200 (P 0.05) and AO400 (P 0.01) groups 90 minutes after intoxication] Conclusion: Based on these authentic results, it seems that olive leaf extracts can be useful in reducing the severity of symptoms in ALP-poisoned individuals and could be utilized in a poisoning emergency.