中科院上海药物研究所科研人员与澳大利亚伽尔文(Garvan)医学研究所合作，从苦瓜中发现了数个具有治疗糖尿病应用前景的活性化合物成分。双方共同的研究结果发表在最新一期《细胞》出版社期刊《化学与生物学》（Chemistry & Biology）杂志上。
苦瓜作为中药使用已有数百年历史。近代对苦瓜化学成分及其药理活性的研究颇多，但其中主要的降糖活性化学物质及其作用机理一直未明确。中科院上海药物研究所研究员叶阳课题组通过多年探索，从苦瓜中分离和鉴定了一系列新的天然化学成分，并与伽尔文研究所合作，在细胞和动物水平上首次明确了这些天然成分具有降低血糖的活性。科学家推测这些化合物在细胞中是通过一条新型信号通路起作用的，进一步发现这条信号通路将对发现研究治疗糖尿病的新途径和发明治疗糖尿病新药都是一件非常有意义的事情。
对化合物的降糖作用机制研究表明，这些化合物能激活体内与能量代谢相关的一个重要蛋白——单磷酸腺苷活化蛋白激酶(AMPK)。该蛋白具有调控人体能量代谢和促进葡萄糖摄取的作用。采取有效措施激活AMPK是2型糖尿病治疗的一个重要途径。
据悉，中科院上海药物研究所和伽尔文研究所已签署了合作协议，将对苦瓜的降糖治疗作用进行深入全面评价和作用机制研究。（来源：科学时报 黄辛）
生物谷推荐原始出处：
（Chemistry & Biology），Vol 15, 263-273, 21 March 2008，Min-Jia Tan, David E. James and Yang Ye
Antidiabetic Activities of Triterpenoids Isolated from Bitter Melon Associated with Activation of the AMPK Pathway
Min-Jia Tan,1,5 Ji-Ming Ye,2,5 Nigel Turner,2,5 Cordula Hohnen-Behrens,2 Chang-Qiang Ke,1 Chun-Ping Tang,1 Tong Chen,1 Hans-Christoph Weiss,3 Ernst-Rudolf Gesing,4 Alex Rowland,2 David E. James,2, and Yang Ye1,
1 State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai 201203, China
2 Diabetes and Obesity Research Program, Garvan Institute of Medical Research, University of New South Wales, Sydney, NSW 2010, Australia
3 Bayer Industry Services GmbH & Co., Leverkusen 51368, Germany
4 Bayer CropScience AG, R & D, Agricultural Center, Monheim 40789, Germany
Summary
Four cucurbitane glycosides, momordicosides Q, R, S, and T, and stereochemistry-established karaviloside XI, were isolated from the vegetable bitter melon (Momordica charantia). These compounds and their aglycones exhibited a number of biologic effects beneficial to diabetes and obesity. In both L6 myotubes and 3T3-L1 adipocytes, they stimulated GLUT4 translocation to the cell membrane—an essential step for inducible glucose entry into cells. This was associated with increased activity of AMP-activated protein kinase (AMPK), a key pathway mediating glucose uptake and fatty acid oxidation. Furthermore, momordicoside(s) enhanced fatty acid oxidation and glucose disposal during glucose tolerance tests in both insulin-sensitive and insulin-resistant mice. These findings indicate that cucurbitane triterpenoids, the characteristic constituents of M. charantia, may provide leads as a class of therapeutics for diabetes and obesity.
