Department of Nutrition & Dietetics, Boshell Diabetes and Metabolic Diseases, Research Program, Auburn University, Auburn, AL 36849, USA.
J Ethnopharmacol. 2012 Sep 28;143(2):481-7. doi: 10.1016/j.jep.2012.06.054. Epub 2012 Jul 14.
Serviceberry or Saskatoon berry [Amelanchier alnifolia (Nutt.) Nutt. ex. M. Roem (Rosaceae)], native to the North Glacier forests of the Rocky Mountains in Montana, has been used by the Blackfeet Indian tribe in alleviation of diabetes. Anecdotally, tea made from twigs and leaves have been used for optimum health and diabetes management. However, such traditional knowledge of the medicinal properties of Amelanchier alnifolia has not been validated by scientific studies. The goal of this study was to identify potential antidiabetic mechanisms of serviceberry.
Serviceberry plant samples consisting of leaves, twigs, and leaves with berries were extracted and fractionated. Ethyl acetate and water fractions were tested for inhibition of α-glucosidase activity in vitro. Diet-induced obese, hyperglycemic C57Bl6 mice were administered serviceberry leaf extract prior to sucrose-, starch-, or glucose-loading to test for α-glucosidase inhibition and decreased post-prandial glycemic response.
In the course of screening for potential antidiabetic mechanisms, serviceberry leaf extracts and subfractions demonstrated potent inhibitory activity against mammalian intestinal α-glucosidase activity (EC 3.2.1.20). Further, in an animal model of diet-induced obesity and hyperglycemia, serviceberry leaf subfraction demonstrated significant inhibition of intestinal α-glucosidase activity, and delayed the absorption of carbohydrates, resulting in significant lowering of post-prandial blood glucose concentrations, similar to the antidiabetic drug Acarbose™.
These findings indicating that serviceberry leaf extract may lower post-prandial glycemic response corroborate traditional knowledge of the Blackfeet Indians of Montana, and potentially offer a complementary approach in the treatment of diabetes.
山桑子或萨斯卡通莓[鹅绒委陵菜（Nutt.）Nutt. ex. M. Roem（蔷薇科）]，原产于蒙大拿州落矶山脉的北冰川森林，已被黑脚族印第安部落用于缓解糖尿病。据传闻，由嫩枝和叶子制成的茶可促进身体健康和糖尿病管理。然而，关于鹅绒委陵菜药用特性的这种传统知识尚未得到科学研究的验证。本研究的目的是确定山桑子的潜在抗糖尿病机制。
山桑子植物样本包括叶子、嫩枝和带浆果的叶子，经过提取和分级。乙酸乙酯和水级分用于体外抑制α-葡萄糖苷酶活性的测试。在给予蔗糖、淀粉或葡萄糖负荷之前，向饮食诱导肥胖、高血糖 C57Bl6 小鼠施用山桑子叶提取物，以测试α-葡萄糖苷酶抑制作用和餐后血糖反应降低。
在筛选潜在抗糖尿病机制的过程中，山桑子叶提取物和次级分显示出对哺乳动物肠道α-葡萄糖苷酶活性（EC 3.2.1.20）的强大抑制活性。此外，在饮食诱导肥胖和高血糖的动物模型中，山桑子叶次级分显示出对肠道α-葡萄糖苷酶活性的显著抑制作用，并延迟碳水化合物的吸收，导致餐后血糖浓度显著降低，与抗糖尿病药物阿卡波糖™相似。
这些发现表明，山桑子叶提取物可能降低餐后血糖反应，与蒙大拿州黑脚族印第安人的传统知识相吻合，并为糖尿病治疗提供一种补充方法。
