摘要Objective: To explore the therapeutic efficacy of L-carvone from Mentha spicata L. leaf extracts against isoproterenol-induced cardiac hypertrophy in rats.Methods: Isoproterenol (5 mg/kg) was injected intraperitoneally into rats for one month to induce cardiac hypertrophy. L-carvone (25 and 100 mg/kg) was administered orally to treat cardiac hypertrophy. The cardioprotective activity of L-carvone was evaluated by electrocardiogram, histopathological analysis as well as determination of biochemical parameters and enzymatic markers. Results: L-carvone from Mentha spicata L. at 25 and 100 mg/kg ameliorated isoproterenol-induced cardiac hypertrophy, as evidenced by reduced QRS interval on electrocardiogram, and decreased heart weight and heart index. In addition, both doses of L-carvone markedly lowered the levels of glucose, total protein, low-density lipoprotein cholesterol, aspartate transaminase, alanine transaminase, lactate dehydrogenase, creatine kinase MB, troponin-Ⅰ, N-terminal pro-B type natriuretic peptide and triglycerides while increasing high-density lipoprotein cholesterol and lipase level (P<0.05). Moreover, L-carvone alleviated contraction band necrosis, and reorganized the myofibrils with normal striations and myocytes as well as normal nuclei in cardiac histoarchitecture of rats with isoproterenol-induced cardiac hypertrophy. Conclusions: L-carvone from Mentha spicata L. leaf extract can restore abnormal cardiac function and may be further explored as a therapeutic agent against the deleterious effects of cardiac hypertrophy after further evaluation.