Njan Anoka A, Adenuga Francisca O, Ajayi Abayomi M, Sotunde Olasubomi, Ologe Mary O, Olaoye Solomon O, Erdogan Ozlem Nazan, Iwalewa Olugbenga E
Department of Pharmacology and Therapeutics, Faculty of Basic Medical Sciences, University of Ilorin, Ilorin, Nigeria.
Neuropharmacology and Ethnopharmacology Unit, Department of Pharmacology and Therapeutics, Faculty of Basic Medical Sciences, College of Medicine, University of Ibadan, Ibadan, Nigeria.
Heliyon. 2020 May 22;6(5):e04011. doi: 10.1016/j.heliyon.2020.e04011. eCollection 2020 May.
This study investigated the effect of methanolic leaf extract of (MEPb) on type 2 diabetes mellitus (T2DM) associated cognitive decline in Wistar rats. 36 male rats weighing 130-200 g were assigned into 6 groups (n = 6) as follows: normal control, diabetic control, pioglitazone-treated diabetic and three MEPb-treated diabetic groups, type 2 diabetes mellitus was induced with low dose streptozocin (STZ) injection following 3 weeks of high fat diet (HFD) intake. Thirty days after diabetes induction, rats exhibited marked and persistent hyperglycemia, animals were treated with MEPb (50, 100 and 200 mg/kg) and pioglitazone (10 mg/kg) as standard. Morris water maze (MWM) test and Novel object recognition test (NORT) were used to assess learning and memory. Blood glucose level, oxidative stress makers, pro-inflammatory marker and acetylcholinestarase activities were analysed. Both MEPb and pioglitazone significantly (P < 0.05) reduced escape latency in treated animals compared to the diabetic control group in the MWM test. Methanolic leaf extract of and pioglitazone also significantly (P < 0.05) increased discrimination index in treated animals compared to the diabetic control group in the novel object recognition test. Serum, brain and liver MDA levels were significantly (P < 0.05) decreased in MEPb and pioglitazone treated rats compared to diabetic control. Serum and liver GSH as well as CAT levels were significantly (P < 0.05) increased while brain GSH and CAT levels shows apparent increase in MEPb and pioglitazone treated rats compared with diabetic control. Treatment with MEPb caused a significant (P < 0.05) decrease in brain nitrite level, interleukin 6 and acetylcholinesterase activity compared to diabetic control group. We conclude that Methanolic leaf extract of enhanced antioxidant capacity and prevented neuroinflammation, consequently improving brain neuronal cholinergic function in experimental animals.
本研究调查了[植物名称]甲醇叶提取物（MEPb）对Wistar大鼠2型糖尿病（T2DM）相关认知衰退的影响。将36只体重130 - 200克的雄性大鼠分为6组（每组n = 6），分组如下：正常对照组、糖尿病对照组、吡格列酮治疗糖尿病组以及三个MEPb治疗糖尿病组。在高脂饮食（HFD）摄入3周后，通过低剂量链脲佐菌素（STZ）注射诱导大鼠患2型糖尿病。糖尿病诱导30天后，大鼠出现明显且持续的高血糖，动物分别接受MEPb（50、100和200毫克/千克）和作为标准药物的吡格列酮（10毫克/千克）治疗。采用Morris水迷宫（MWM）试验和新物体识别试验（NORT）评估学习和记忆能力。分析血糖水平、氧化应激标志物、促炎标志物和乙酰胆碱酯酶活性。在MWM试验中，与糖尿病对照组相比，MEPb和吡格列酮均显著（P < 0.05）降低了治疗组动物的逃避潜伏期。在新物体识别试验中，与糖尿病对照组相比，[植物名称]甲醇叶提取物和吡格列酮也显著（P < 0.05）提高了治疗组动物的辨别指数。与糖尿病对照组相比，MEPb和吡格列酮治疗的大鼠血清、脑和肝脏丙二醛（MDA）水平显著（P < 0.05）降低。与糖尿病对照组相比，MEPb和吡格列酮治疗的大鼠血清和肝脏谷胱甘肽（GSH）以及过氧化氢酶（CAT）水平显著（P < 0.05）升高，而脑GSH和CAT水平也有明显升高。与糖尿病对照组相比，MEPb治疗使脑亚硝酸盐水平、白细胞介素6和乙酰胆碱酯酶活性显著（P < 0.05）降低。我们得出结论，[植物名称]甲醇叶提取物增强了抗氧化能力并预防了神经炎症，从而改善了实验动物的脑神经元胆碱能功能。
