Chemical composition and ameliorative effect of tomato on isoproterenol-induced myocardial infarction in rats

Abstract

Background and Objective: Tomatoes are rich in active components, such as polyphenols and carotenoids. This study investigated the chemical composition of tomato fruit and the ability of fruits and their pomace (peel, pulp and seeds) to protect against isoproterenol-induced myocardial infarction in rats. Materials and Methods: The proximate chemical composition and the concentrations of some minerals (Ca, Fe, Zn and K), vitamins (C, A, B1, B2 and B6) and antioxidants (β-carotene, lycopene and total phenolic compounds) were estimated in tomato fruits. About 40 rats were injected subcutaneously with isoproterenol dissolved in normal saline at the dose of 100 mg kg-1 daily for 3 consecutive days to induce acute myocardial infarction. Then, rats were classified into the untreated group (positive control) and four treated groups (tomato peel, seed, pulp and whole fruit). Results: The tomato fruits were rich in carbohydrate, protein and fiber but contained little lipid. Phenolic compounds, vitamin C, lycopene, vitamin A and calcium were detected. Compared to the control group, rats fed tomato peel, seeds, pulp and whole fruit had significantly increased body weight gain and food efficiency ratio. Compared to the control group, the tomato-fed groups had decreased total cholesterol, triglycerides and low- and very low-density lipoprotein cholesterol and increased high-density lipoprotein cholesterol. A decrease in serum liver enzyme activity and an increase in antioxidant enzymes in the tomato-fed rats were detected. Conclusion: Administration of tomato and its components has protective effects against isoproterenol-induced myocardial infarction in rats.