Pharmaceutical Institute of the University of Bonn, Bonn, Germany.
J Ethnopharmacol. 2012 Jan 31;139(2):493-6. doi: 10.1016/j.jep.2011.11.039. Epub 2011 Dec 1.
In Mexico, Opuntia streptacantha is used as part of a traditional medicine in the treatment of diabetes mellitus. Several studies have reported an anti-hyperglycemic effect from the plant, but none have focused on finding a mechanism of action to explain these results. This paper focuses on one of the most recurrent hypotheses for the effect of O. streptacantha: the mechanism of action is the hydrolysis of disaccharides, either by enzymatically inhibiting the alpha glucosidase inhibitors (AGIs) or mechanically acting as a barrier.
To test our hypothesis, three different experiments were performed. A maltose tolerance test was carried out using the total extract (TE) and the juice of the plant. Six different extracts were tested in a free-enzyme assay, four of which were aqueous extracts varying according to the procedure of removing the insoluble particles in an attempt to reduce the loss of the water-soluble compounds. The main component of the total extract, a derivative of (4-hydroxy)-phenyl acetic acid, was also tested. For both the maltose tolerance test and the free-enzyme assay, acarbose was used as a control drug. Finally, an everted small intestine assay was also performed.
The maltose tolerance test confirmed that an anti-hyperglycemic effect occurs at doses of 100 mg/kg TE and 4 mL/kg juice. No inhibition on AGIs was observed in the free-enzyme assay, and neither a mechanic nor enzymatic effect on disaccharide hydrolysis was observed in the everted intestine assay.
The anti-hyperglycemic effect of O. streptacantha was confirmed, and the results presented here contribute to the understanding that this effect is not due to the action on alpha-glucosidases or related to the intestinal hydrolysis of disaccharides.
在墨西哥，仙人球（Opuntia streptacantha）被用作传统医学的一部分，用于治疗糖尿病。多项研究报告称，该植物具有降血糖作用，但没有一项研究专注于寻找作用机制来解释这些结果。本文聚焦于仙人球作用的一个最常见假说：作用机制是水解双糖，通过酶抑制α葡萄糖苷酶抑制剂（AGIs）或机械作用作为屏障。
为了验证我们的假说，进行了三项不同的实验。使用总提取物（TE）和植物汁进行麦芽糖耐量试验。在自由酶测定中测试了六种不同的提取物，其中四种是根据去除不溶性颗粒的程序的水提取物，试图减少水溶性化合物的损失。总提取物的主要成分，（4-羟基）-苯乙酸的衍生物，也进行了测试。麦芽糖耐量试验和自由酶测定均使用阿卡波糖作为对照药物。最后，还进行了外翻小肠测定。
麦芽糖耐量试验证实，在 100mg/kg TE 和 4mL/kg 汁的剂量下会出现降血糖作用。在自由酶测定中未观察到对 AGIs 的抑制作用，在外翻肠测定中也未观察到双糖水解的机械或酶作用。
确认了仙人球的降血糖作用，本文的结果有助于理解该作用不是由于对α-葡萄糖苷酶的作用或与肠道双糖水解有关。
