Khorsand Marjan, Akmali Masoumeh, Akhzari Morteza
1Department of Biochemistry and Molecular Biology, Shahid Sadoughi University of Medical Sciences, Fars-shiraz-meshkinfam St.-paramedical school-Department of laboratory sciences, Yazd, Iran.
2Department of Biochemistry, Shiraz University of Medical Sciences, Medical School, P.O box: 71345 1167, Shiraz, Iran.
J Diabetes Metab Disord. 2019 Dec 2;18(2):543-549. doi: 10.1007/s40200-019-00445-8. eCollection 2019 Dec.
Melatonin is a well-known free radical scavenger. The present study aimed to investigate the effects of melatonin treatment on the antioxidant status in the lenticular tissue of streptozotocin (STZ)-induced diabetic rats.
Thirty-four male rats were randomly divided into four groups as follows: healthy control rats (group 1, = 10); diabetic control rats (group 2, = 10); melatonin-treated (5 mg/kg·day) diabetic rats (group 3, = 10) and melatonin-treated (5 mg/kg·day) healthy rats (group 4, = 4). Diabetes was induced by injection of streptozotocin (50 mg/kg, ip). Following 8-weeks of melatonin treatment, all rats were killed and the blood plasma and their lenses were stored at -70 °C for antioxidant enzyme activities assay and biochemical determination.
The plasma glucose and lens malondialdehyde (MDA) increased significantly in the rats of group 2 as compared to the group 1. Also, a significant decrease in the levels of catalase (CAT) and glutathione reductase (GR) activities in the lenses and plasma reduced glutathione (GSH) was found. However, the levels of lenticular MDA (not significant) and the plasma glucose significantly decreased in the rats of group 3 compared to the group 2. Besides, the levels of CAT, GR in the rats lens and plasma GSH increased significantly.
Diabetes mellitus induced hyperglycemia and oxidative stress, whereas melatonin decreased the blood glucose levels and lipid peroxidation and increased the activities of antioxidant enzymes in diabetic rat lenses.
褪黑素是一种著名的自由基清除剂。本研究旨在探讨褪黑素治疗对链脲佐菌素（STZ）诱导的糖尿病大鼠晶状体组织抗氧化状态的影响。
34只雄性大鼠随机分为四组：健康对照大鼠（第1组，n = 10）；糖尿病对照大鼠（第2组，n = 10）；褪黑素治疗（5毫克/千克·天）的糖尿病大鼠（第3组，n = 10）和褪黑素治疗（5毫克/千克·天）的健康大鼠（第4组，n = 4）。通过注射链脲佐菌素（50毫克/千克，腹腔注射）诱导糖尿病。褪黑素治疗8周后，处死所有大鼠，将血浆及其晶状体储存在-70°C用于抗氧化酶活性测定和生化测定。
与第1组相比，第2组大鼠的血浆葡萄糖和晶状体丙二醛（MDA）显著增加。此外，还发现晶状体和血浆中过氧化氢酶（CAT）和谷胱甘肽还原酶（GR）活性水平以及血浆还原型谷胱甘肽（GSH）显著降低。然而，与第2组相比，第3组大鼠晶状体MDA水平（无显著性差异）和血浆葡萄糖显著降低。此外，大鼠晶状体中CAT、GR水平以及血浆GSH显著增加。
糖尿病会导致高血糖和氧化应激，而褪黑素可降低糖尿病大鼠晶状体的血糖水平和脂质过氧化，并增加抗氧化酶的活性。
