Department of Morphology and Animal Physiology, Federal Rural University of Pernambuco, Recife, Brazil.
Department of Veterinary Medicine, Federal Rural University of Pernambuco, Recife, Brazil.
Chem Biol Interact. 2020 Aug 25;327:109183. doi: 10.1016/j.cbi.2020.109183. Epub 2020 Jun 15.
The present study analyzed whether melatonin could mediate the expression of VEGF, IL-6 and TNF-α, as well as the apoptotic index in rats with diabetic retinopathy. Fifty Wistar albino rats were divided into the following groups: GC: rats without induction of diabetes by streptozotocin; GD: rats induced to diabetes by streptozotocin and treated with placebo; GDM: rats induced to diabetes by streptozotocin and after confirmation treated with melatonin at a dose of 10 mg/kg for 20 days; GDMS: rats induced to diabetes by streptozotocin and treated simultaneously with melatonin at a dosage of 10 mg/kg for 20 days; GDI: rats induced to diabetes by streptozotocin and after confirmation treated with insulin for 20 days. Diabetes was induced by intraperitoneal injections of streptozotocin (60 mg/kg), and insulin (5 U/day) was administered subcutaneously. For apoptosis TUNEL was used, while for the analysis of VEGF, IL-6 and TNF-α. The results showed that the groups that were treated with melatonin decreased the expression of cytokines and VEGF, in addition to apoptosis. Thus, it is concluded that melatonin can regulate the expression of these factors by improving the condition of the retina in diabetic retinopathy.
本研究分析了褪黑素是否可以调节糖尿病视网膜病变大鼠中 VEGF、IL-6 和 TNF-α 的表达以及细胞凋亡指数。将 50 只 Wistar 白化大鼠分为以下几组：GC 组：未用链脲佐菌素诱导糖尿病的大鼠；GD 组：用链脲佐菌素诱导糖尿病并给予安慰剂的大鼠；GDM 组：用链脲佐菌素诱导糖尿病并在确认后用 10mg/kg 褪黑素治疗 20 天的大鼠；GDMS 组：用链脲佐菌素诱导糖尿病并同时用 10mg/kg 褪黑素治疗 20 天的大鼠；GDI 组：用链脲佐菌素诱导糖尿病并在确认后用胰岛素治疗 20 天的大鼠。糖尿病通过腹腔注射链脲佐菌素（60mg/kg）诱导，皮下注射胰岛素（5U/天）。用 TUNEL 法检测细胞凋亡，用 VEGF、IL-6 和 TNF-α 分析。结果表明，用褪黑素治疗的组降低了细胞因子和 VEGF 的表达，以及细胞凋亡。因此，可以得出结论，褪黑素可以通过改善糖尿病视网膜病变中视网膜的状况来调节这些因素的表达。
