Ibrahim Mohammed Auwal, Habila James Dama, Koorbanally Neil Anthony, Islam Md Shahidul
School of Life Sciences, University of KwaZulu-Natal (Westville Campus), Durban 4000 South Africa; Department of Biochemistry, Ahmadu Bello University, Zaria, Nigeria.
School of Chemistry, University of KwaZulu-Natal (Westville Campus), Durban 4000 South Africa.
J Ethnopharmacol. 2016 May 13;183:103-111. doi: 10.1016/j.jep.2016.02.018. Epub 2016 Feb 18.
Ethnopharmacological surveys have reported that Parkia biglobosa (Jacq.) G. Don (Leguminosae) is among the plants commonly used in the traditional management of diabetes mellitus in Nigeria and Togo.
This study investigated the anti-diabetic activity of the butanol fraction of P. biglobosa leaves (PBBF) in a type 2 diabetes (T2D) model of rats and a possible bioactive compound in the fraction.
T2D was induced by feeding rats with a 10% fructose solution ad libitum for two weeks followed by an intraperitoneal injection of 40mg/kg body weight streptozotocin and the animals were orally treated with 150 and 300mg/kg BW of the PBBF for five days in a week. Another group of rats was non-diabetic but similarly administered with 300mg/kg BW of the PBBF. Food and fluid intakes, body weight changes and blood glucose levels were monitored during the experiment while other relevant diabetes-associated parameters were measured at the end of the experiment.
The PBBF treatments significantly (P<0.05) decreased the blood glucose levels and improved the glucose tolerance ability compared to untreated diabetic rats. Furthermore, the treatments were found to improve pancreatic β cell function (HOMA-β), stimulate insulin secretions, decrease insulin resistance (HOMA-IR), restore liver glycogen, ameliorate serum dyslipidaemia and prevent hepatic and renal damages compared to untreated diabetic rats. Phytochemical analysis of the fraction led to the isolation of lupeol which inhibited α-glucosidase and α-amylase in non-competitive and uncompetitive inhibition patterns respectively.
It was concluded that PBBF possessed remarkable anti-T2D activity which is mediated through modulation of β-cell function and stimulation of insulin secretion and the lower dose (150mg/kg BW) was found optimum for anti-T2D activity compared to the high dose (300mg/kg BW) in this study.
民族药理学调查表明，在尼日利亚和多哥，腊肠树（豆科）是传统治疗糖尿病常用的植物之一。
本研究在2型糖尿病（T2D）大鼠模型中，研究了腊肠树叶正丁醇部位（PBBF）的抗糖尿病活性以及该部位中可能的生物活性化合物。
通过随意给大鼠喂食10%果糖溶液两周，随后腹腔注射40mg/kg体重链脲佐菌素诱导T2D，动物每周口服150和300mg/kg体重的PBBF，持续五天。另一组大鼠非糖尿病，但同样给予300mg/kg体重的PBBF。实验期间监测食物和液体摄入量、体重变化及血糖水平，实验结束时测量其他相关糖尿病相关参数。
与未治疗的糖尿病大鼠相比，PBBF治疗显著（P<0.05）降低了血糖水平，提高了葡萄糖耐量能力。此外，与未治疗的糖尿病大鼠相比，这些治疗还改善了胰腺β细胞功能（HOMA-β），刺激了胰岛素分泌，降低了胰岛素抵抗（HOMA-IR），恢复了肝糖原，改善了血清血脂异常，并预防了肝和肾损伤。对该部位进行植物化学分析，分离出羽扇豆醇，其分别以非竞争性和非竞争性抑制模式抑制α-葡萄糖苷酶和α-淀粉酶。
得出结论，PBBF具有显著的抗T2D活性，其通过调节β细胞功能和刺激胰岛素分泌介导，并且在本研究中，低剂量（150mg/kg体重）被发现比高剂量（300mg/kg体重）更适合抗T2D活性。
