Rebelos Eleni, Rinne Juha O, Nuutila Pirjo, Ekblad Laura L
Turku PET Centre, University of Turku and Turku University Hospital, 20520 Turku, Finland.
Department of Endocrinology, Turku University Hospital, 20520 Turku, Finland.
J Clin Med. 2021 Apr 6;10(7):1532. doi: 10.3390/jcm10071532.
Imaging brain glucose metabolism with fluorine-labelled fluorodeoxyglucose ([F]-FDG) positron emission tomography (PET) has long been utilized to aid the diagnosis of memory disorders, in particular in differentiating Alzheimer's disease (AD) from other neurological conditions causing cognitive decline. The interest for studying brain glucose metabolism in the context of metabolic disorders has arisen more recently. Obesity and type 2 diabetes-two diseases characterized by systemic insulin resistance-are associated with an increased risk for AD. Along with the well-defined patterns of fasting [F]-FDG-PET changes that occur in AD, recent evidence has shown alterations in fasting and insulin-stimulated brain glucose metabolism also in obesity and systemic insulin resistance. Thus, it is important to clarify whether changes in brain glucose metabolism are just an epiphenomenon of the pathophysiology of the metabolic and neurologic disorders, or a crucial determinant of their pathophysiologic cascade. In this review, we discuss the current knowledge regarding alterations in brain glucose metabolism, studied with [F]-FDG-PET from metabolic disorders to AD, with a special focus on how manipulation of insulin levels affects brain glucose metabolism in health and in systemic insulin resistance. A better understanding of alterations in brain glucose metabolism in health, obesity, and neurodegeneration, and the relationships between insulin resistance and central nervous system glucose metabolism may be an important step for the battle against metabolic and cognitive disorders.
长期以来，利用氟标记的氟脱氧葡萄糖（[F]-FDG）正电子发射断层扫描（PET）对大脑葡萄糖代谢进行成像，有助于诊断记忆障碍，特别是用于区分阿尔茨海默病（AD）与其他导致认知衰退的神经疾病。最近，人们对在代谢紊乱背景下研究大脑葡萄糖代谢的兴趣日益浓厚。肥胖症和2型糖尿病这两种以全身胰岛素抵抗为特征的疾病，与患AD的风险增加有关。除了AD中出现的明确的空腹[F]-FDG-PET变化模式外，最近的证据还表明，肥胖症和全身胰岛素抵抗患者在空腹和胰岛素刺激下的大脑葡萄糖代谢也存在改变。因此，明确大脑葡萄糖代谢的变化仅仅是代谢和神经疾病病理生理学的一种附带现象，还是其病理生理级联反应的关键决定因素，这一点很重要。在这篇综述中，我们讨论了目前关于大脑葡萄糖代谢改变的知识，这些知识是通过[F]-FDG-PET从代谢紊乱到AD进行研究的，特别关注胰岛素水平的调控如何影响健康状态下以及全身胰岛素抵抗状态下的大脑葡萄糖代谢。更好地理解健康、肥胖和神经退行性变状态下大脑葡萄糖代谢的改变，以及胰岛素抵抗与中枢神经系统葡萄糖代谢之间的关系，可能是对抗代谢和认知障碍的重要一步。
