BMC Complement Altern Med. 2013 Jul 15;13:175. doi: 10.1186/1472-6882-13-175.
Diabetes mellitus (DM) is a metabolic disease characterized by chronic hyperglycaemia generally associated with oxidative stress. The present study aims at evaluating the antioxidant and antidiabetic potential of methanol and hydroethanol extracts of the stem bark and leaves of Pricralima nitida and the Sonchus oleraceus whole plant respectively.
The in vitro antioxidant activity was assessed using 1,1-Diphenyl-2-picrilhydrazyl (DPPH) for free radical-scavenging properties of the extracts, and the Folin-Ciocalteu method in determining their phenol contents. The antidiabetic activity was tested in mice following streptozotocin diabetes induction, and selected oxidative stress markers (Malondialdehyde, Hydrogen peroxides and Catalase) were measured in order to evaluate the level of oxidative stress in treated animals.
The in vitro antioxidant activity using DPPH showed IC50 ranging from 0.19 ± 0.08 to 1.00 ± 0.06 mg/mL. The highest activity was obtained with the hydroethanol extracts of S. oleraceus (0.19 mg/mL and P. nitida (0.24 mg/mL). Polyphenol contents ranged from 182.25 ± 16.76 to 684.62 ± 46.66 μg Eq Cat/g. The methanol extract of P. nitida showed the highest activity, followed by the hydroethanol extract of S. oleraceus (616.89 ± 19.20 μEq Cat/g). The hydroethanol extract of whole plants (150 mg/Kg) and methanol leave extract of P. nitida (300 mg/Kg) exhibited significant antidiabetic activities with 39.40% and 38.48% glycaemia reduction, respectively. The measurement of stress markers in plasma, liver and kidney after administration of both extracts showed significant reduction in MDA and hydrogen peroxide levels, coupled with a substantial increase in catalase activity.
These findings suggest that S. oleraceus whole plant and P. nitida leaves possess both antidiabetic and antioxidant properties, and therefore could be used as starting point for the development of herbal medicines and/or source of new drug molecules against diabetes.
糖尿病（DM）是一种代谢性疾病，其特征为慢性高血糖，通常与氧化应激有关。本研究旨在评估甲醇和水乙醇提取物分别从 Priacrima nitida 的茎皮和叶以及 Sonchus oleraceus 的全草中提取的抗氧化和抗糖尿病潜力。
使用 1,1-二苯基-2-苦基肼（DPPH）评估提取物的自由基清除特性，以评估其酚含量的 Folin-Ciocalteu 法评估体外抗氧化活性。使用链脲佐菌素诱导糖尿病后在小鼠中测试抗糖尿病活性，并测量选定的氧化应激标志物（丙二醛、过氧化氢和过氧化氢酶），以评估治疗动物的氧化应激水平。
使用 DPPH 的体外抗氧化活性显示 IC50 范围为 0.19±0.08 至 1.00±0.06mg/mL。水乙醇提取物的 S. oleraceus（0.19mg/mL 和 P. nitida（0.24mg/mL）的活性最高。多酚含量范围为 182.25±16.76 至 684.62±46.66μgEq Cat/g。P. nitida 的甲醇提取物表现出最高的活性，其次是 S. oleraceus 的水乙醇提取物（616.89±19.20μEq Cat/g）。全植物的水乙醇提取物（150mg/Kg）和 P. nitida 的甲醇叶提取物（300mg/Kg）分别显示出 39.40%和 38.48%的血糖降低，具有显著的抗糖尿病活性。在给予两种提取物后，在血浆、肝和肾中测量应激标志物显示 MDA 和过氧化氢水平显著降低，同时过氧化氢酶活性显著增加。
这些发现表明，S. oleraceus 全草和 P. nitida 叶具有抗糖尿病和抗氧化特性，因此可作为开发草药药物和/或对抗糖尿病的新药物分子的起点。
