Division of Cardiovascular Medicine, Brigham and Women's Hospital, Boston, MA, USA.
JACC Cardiovasc Imaging. 2010 Aug;3(8):843-51. doi: 10.1016/j.jcmg.2010.06.004.
The current study tested the hypothesis that glucose utilization differs between visceral adipose tissue (VAT) and subcutaneous adipose tissue (SAT), and investigated potential mechanisms for such a finding.
VAT burden correlates better with cardiovascular risk than does SAT burden. Beyond volumetric measurement, glucose uptake in adipose tissue (AT) might reflect metabolic activity and provide pathophysiologic insight and aid risk stratification.
We retrospectively studied tissue-specific glucose uptake in vivo in clinically obtained whole-body fluorodeoxyglucose positron emission tomography (FDG-PET) scans in humans. We also assessed glucose uptake in vitro, using stromal vascular cells isolated from SAT and VAT of diet-induced obese C57BL/6 mice. Quantitative polymerase chain reaction (PCR) evaluated the expression of multiple genes involved in cellular glucose metabolism, including glucose transporters (GLUT-1, -3, and -4) and hexokinases (HK-1 and -2) in SAT and VAT of obese C57BL/6 mice.
We analyzed whole-body FDG-PET scans from 31 obese and 26 lean patients. VAT exhibited higher FDG uptake compared with SAT (p < 0.0001) independent of age, sex, body mass index, comorbidities, and medications. To investigate mechanisms underlying this observation, we studied glucose uptake in the stromal vascular cell fraction of AT, which is rich in inflammatory cells. Stromal vascular cells from VAT of diet-induced obese C57BL/6 mice exhibited higher glucose uptake than those from SAT (p = 0.01). Evaluation of expression of glucose transporters (GLUT-1, -3, and -4) and hexokinases (HK-1 and -2), revealed increased expression of HK-1 in VAT-derived compared with SAT-derived stromal vascular cells, and also in visceral versus subcutaneous unfractionated AT.
In humans in vivo, VAT has increased glucose uptake compared with SAT, as determined noninvasively with FDG PET imaging. Differential stromal metabolic activity may be 1 mechanism underlying differences in metabolic activity of visceral and subcutaneous AT.
本研究旨在验证内脏脂肪组织（VAT）和皮下脂肪组织（SAT）的葡萄糖利用率存在差异这一假说，并探讨这一发现的潜在机制。
与 SAT 负担相比，VAT 负担与心血管风险的相关性更好。除了体积测量外，脂肪组织（AT）中的葡萄糖摄取量可能反映代谢活性，并提供病理生理学见解和帮助风险分层。
我们回顾性地研究了临床获得的全身氟脱氧葡萄糖正电子发射断层扫描（FDG-PET）扫描中体内组织特异性葡萄糖摄取情况。我们还评估了饮食诱导肥胖 C57BL/6 小鼠 SAT 和 VAT 分离的基质血管细胞的体外葡萄糖摄取情况。定量聚合酶链反应（PCR）评估了肥胖 C57BL/6 小鼠 SAT 和 VAT 中涉及细胞葡萄糖代谢的多个基因的表达，包括葡萄糖转运蛋白（GLUT-1、-3 和 -4）和己糖激酶（HK-1 和 -2）。
我们分析了 31 名肥胖患者和 26 名瘦患者的全身 FDG-PET 扫描。VAT 的 FDG 摄取量高于 SAT（p < 0.0001），与年龄、性别、体重指数、合并症和药物无关。为了研究这一观察结果的机制，我们研究了富含炎症细胞的 AT 基质血管细胞部分的葡萄糖摄取。饮食诱导肥胖 C57BL/6 小鼠 VAT 的基质血管细胞比 SAT 的摄取量更高（p = 0.01）。葡萄糖转运蛋白（GLUT-1、-3 和 -4）和己糖激酶（HK-1 和 -2）的表达评估显示，与 SAT 衍生的基质血管细胞相比，VAT 衍生的基质血管细胞中 HK-1 的表达增加，并且在未分离的内脏和皮下 AT 中也是如此。
在体内，通过 FDG PET 成像非侵入性地确定，与 SAT 相比，VAT 的葡萄糖摄取增加。内脏和皮下 AT 代谢活性的差异可能是基质代谢活性差异的 1 种机制。
