Effect of melatonin on myocardial injury caused by diabetes mellitus

  AIM  To study the effect of melatonin (MLT) on myocardial damage caused by diabetes mellitus induced by streptozotocin (STZ).

  METHODS  SD rats were randomly divided into a control group, a diabetes mellitus group (DM), and a medicated group. The diabetes mellitus model was established by intraperitoneal injection of STZ (50 mg/kg) for 5 days. After the DM model was established, the medicated group was treated with melatonin (30 mg/kg) for 8 weeks. Fasting blood glucose (FBG) was measured by Roche glucometer, serum insulin levels were measured by kit, and cardiac function was measured by echocardiography. Heart histology and morphology was observed with HE and Masson trichrome stain. Myocardial apoptosis was detected by TUNEL and humoral factors in serum were measured by Elisa kit.

  RESULTS  In the MLT group, FBG decreased, serum insulin increased, cardiac systolic and diastolic functions improved, ruined form and frame of myocardium ameliorated, myocardial apoptosis decreased, serum malonaldehyde, TNF-α, IL-1β decreased, and serum superoxide dismutase and catalase increased,compared with those in the DM group.

  CONCLUSION  Melatonin ameliorates myocardial damage caused by diabetic mellitus and further study is needed to demonstrate the underlying mechanism.