Central nervous system (CNS) insulin resistance is associated with Alzheimer's disease (AD). In addition, the apolipoprotein E4 (apoE4) isoform is a risk factor for AD. The connection between these two factors in relation to AD is being actively explored. We summarize this literature with a focus on the transport of insulin and apoE across the blood-brain barrier (BBB) and into the CNS, the impact of apoE and insulin on the BBB, and the interactions between apoE, insulin, and the insulin receptor once present in the CNS. We highlight how CNS insulin resistance is apparent in AD and potential ways to overcome this resistance by repurposing currently approved drugs, with apoE genotype taken into consideration as the treatment response following most interventions is apoE isoform-dependent. This review is part of a special issue focusing on apoE in AD and neurodegeneration.

中文翻译：

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ApoE 和脑胰岛素：贩运、受体和抵抗。

中枢神经系统 (CNS) 胰岛素抵抗与阿尔茨海默病 (AD) 相关。此外，载脂蛋白 E4 (apoE4) 亚型是 AD 的危险因素。人们正在积极探索这两个因素与 AD 之间的联系。我们总结了这篇文献，重点关注胰岛素和 apoE 穿过血脑屏障 (BBB) 进入 CNS、apoE 和胰岛素对 BBB 的影响，以及 apoE、胰岛素和胰岛素受体之间的相互作用一旦出现在中枢神经系统中。我们强调中枢神经系统胰岛素抵抗在 AD 中是如何明显的，以及通过重新利用目前批准的药物来克服这种抵抗的潜在方法，并考虑 apoE 基因型，因为大多数干预措施后的治疗反应是 apoE 同工型依赖性的。这篇综述是关注 AD 和神经退行性疾病中 apoE 的特刊的一部分。