Acibadem University, School of Medicine, Department of Physiology, 34684, Istanbul, Turkey.
Faculty of Medicine, Department of Biophysics, Bezmialem Vakif University, Istanbul, Turkey.
Tissue Cell. 2022 Jun;76:101763. doi: 10.1016/j.tice.2022.101763. Epub 2022 Feb 22.
Type 2 diabetes mellitus (T2DM) is a widely prevalent chronic disease and risk factor for several other diseases, such as cardiovascular diseases, neuropathy, nephropathy, and retinopathy. Apoptosis is a homeostatic mechanism to maintain cell numbers at a certain level in tissues. Chronic high blood glucose levels might lead to mitochondrial dysfunction and trigger undesirable apoptosis in T2DM. The pineal hormone melatonin has been shown to regulate apoptosis. The aim of this study was to investigate the impact of the melatonin MT receptor in the role of melatonin to prevent undesirable apotosis in different tissues of diabetic rats. Male Sprague Dawley rats were randomly divided into 4 groups; 1. Control group (only vehicle), 2. Diabetic group (streptozotozin/nicotinamide treated), 3. Diabetic group treated with melatonin (500μg/kg/day), and 4. Diabetic group treated with melatonin (500 μg/kg/day for 6 weeks) and the selective MT receptor antagonist luzindole (0.25 g/kg/day for 6 weeks). Various tissue samples (kidney, liver, adipose tissue, pancreas) were removed after 6 weeks for immunohistochemistry and western blot analysis. Our results demonstrated an increased rate of apoptosis in different tissues of diabetic rats compared to controls with melatonin reducing the apoptotic rate in the tissues of rats with T2DM. Furthermore, the anti-apoptotic effects of melatonin were partly mediated by the melatonin MT receptor.
2 型糖尿病（T2DM）是一种广泛存在的慢性疾病，也是多种其他疾病的风险因素，如心血管疾病、神经病、肾病和视网膜病变。细胞凋亡是一种维持组织中细胞数量在一定水平的体内平衡机制。慢性高血糖水平可能导致线粒体功能障碍，并在 T2DM 中引发不良的细胞凋亡。松果腺激素褪黑素已被证明可以调节细胞凋亡。本研究旨在探讨褪黑素 MT 受体在褪黑素预防糖尿病大鼠不同组织中不良细胞凋亡中的作用。雄性 Sprague Dawley 大鼠随机分为 4 组：1. 对照组（仅给予载体），2. 糖尿病组（链脲佐菌素/烟酰胺处理），3. 褪黑素治疗的糖尿病组（500μg/kg/天），4. 褪黑素治疗的糖尿病组（500μg/kg/天，持续 6 周）和选择性 MT 受体拮抗剂 luzindole（0.25g/kg/天，持续 6 周）。6 周后，从各组大鼠中取出各种组织样本（肾脏、肝脏、脂肪组织、胰腺）进行免疫组织化学和 Western blot 分析。我们的研究结果表明，与对照组相比，糖尿病大鼠的不同组织中的细胞凋亡率增加，而褪黑素降低了 T2DM 大鼠组织中的细胞凋亡率。此外，褪黑素的抗细胞凋亡作用部分是通过褪黑素 MT 受体介导的。
