9 胰島素樣生長因子-I改善血腦屏障改變
已有大量研究證明血腦屏障的改變是糖尿病認知功能障礙的發(fā)病機制之一。糖尿病患者腦微血管病變普遍存在,而血腦屏障(BBB)是腦微血管獨特的生理功能,其從結構到功能發(fā)生了一系列的改變,其中包括轉運功能的改變——葡萄糖BBB轉運減少(這可能是CNS對長期高血糖毒性作用的一種適應)。其機制是葡萄糖轉運子(GLU-I)的表達減少,從而引起腦組織對葡萄糖的攝入減低,導致認知功能障礙[25]。而近來有研究證明IGF-I可以提高GLU-I轉運葡萄糖的能力。因此IGF-I可以通過改善BBB葡萄糖的轉運來改善認知功能。
綜上所述,IGF-I與糖尿病認知功能障礙之間存在著密切的聯(lián)系,IGF-I可從很多機制上改善糖尿病認知功能障礙。但糖尿病認知功能障礙的發(fā)病機制十分復雜,IGF-I參與糖尿病認知功能障礙的機制還不十分明確,在這方面我們尚有大量工作要做。且目前尚無IGF-I用于改善糖尿病認知功能障礙的臨床實驗研究。期待有一天IGF-I可以在臨床上應用來改善糖尿病患者的認知功能,為提高其生活質量作出貢獻。
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