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9 胰岛素样生长因子-I改善血脑屏障改变
已有大量研究证明血脑屏障的改变是糖尿病认知功能障碍的发病机制之一。糖尿病患者脑微血管病变普遍存在，而血脑屏障（BBB)是脑微血管独特的生理功能，其从结构到功能发生了一系列的改变，其中包括转运功能的改变——葡萄糖BBB转运减少（这可能是CNS对长期高血糖毒性作用的一种适应)。其机制是葡萄糖转运子（GLU-I)的表达减少，从而引起脑组织对葡萄糖的摄入减低，导致认知功能障碍［25］。而近来有研究证明IGF-I可以提高GLU-I转运葡萄糖的能力。因此IGF-I可以通过改善BBB葡萄糖的转运来改善认知功能。
综上所述，IGF-I与糖尿病认知功能障碍之间存在着密切的联系，IGF-I可从很多机制上改善糖尿病认知功能障碍。但糖尿病认知功能障碍的发病机制十分复杂，IGF-I参与糖尿病认知功能障碍的机制还不十分明确，在这方面我们尚有大量工作要做。且目前尚无IGF-I用于改善糖尿病认知功能障碍的临床实验研究。期待有一天IGF-I可以在临床上应用来改善糖尿病患者的认知功能，为提高其生活质量作出贡献。
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