Diabetes Center, Department of Internal Medicine, VU University Medical Center, Amsterdam, the Netherlands.
Diabetes. 2013 Aug;62(8):2898-904. doi: 10.2337/db12-1159. Epub 2013 Mar 25.
Subclinical systemic microvascular dysfunction exists in asymptomatic patients with type 1 diabetes. We hypothesized that microangiopathy, resulting from long-standing systemic hyperglycemia and hyperinsulinemia, may be generalized to the brain, resulting in changes in cerebral blood flow (CBF) and metabolism in these patients. We performed dynamic [(15)O]H2O and [(18)F]-fluoro-2-deoxy-d-glucose brain positron emission tomography scans to measure CBF and cerebral glucose metabolism (CMRglu), respectively, in 30 type 1 diabetic patients and 12 age-matched healthy controls after an overnight fast. Regions of interest were automatically delineated on coregistered magnetic resonance images and full kinetic analysis was performed. Plasma glucose and insulin levels were higher in patients versus controls. Total gray matter CBF was 9%, whereas CMRglu was 21% lower in type 1 diabetic subjects versus control subjects. We conclude that at real-life fasting glucose and insulin levels, type 1 diabetes is associated with decreased resting cerebral glucose metabolism, which is only partially explained by the decreased CBF. These findings suggest that mechanisms other than generalized microangiopathy account for the altered CMRglu observed in well-controlled type 1 diabetes.
无症状 1 型糖尿病患者存在亚临床系统性微血管功能障碍。我们假设，长期的全身性高血糖和高胰岛素血症引起的微血管病变可能会扩散到大脑，导致这些患者的脑血流量 (CBF) 和代谢发生变化。我们对 30 名 1 型糖尿病患者和 12 名年龄匹配的健康对照者进行了 [(15)O]H2O 和 [(18)F]-氟代-2-脱氧-d-葡萄糖脑正电子发射断层扫描，以分别测量 CBF 和脑葡萄糖代谢 (CMRglu)。在禁食一夜后进行了这些检查。通过自动描绘配准磁共振图像上的感兴趣区域并进行完整的动力学分析来进行测量。与对照组相比，患者的血浆葡萄糖和胰岛素水平更高。1 型糖尿病患者的全脑灰质 CBF 降低了 9%，而 CMRglu 则降低了 21%。我们的结论是，在现实生活中的空腹血糖和胰岛素水平下，1 型糖尿病与静息脑葡萄糖代谢降低有关，而这种降低仅部分由 CBF 降低解释。这些发现表明，在控制良好的 1 型糖尿病中观察到的 CMRglu 改变，其机制不仅仅是全身性微血管病变。
