Department of Biomedical Sciences, Center for Healthy Aging, University of Copenhagen, Copenhagen, Denmark.
Diabetes. 2010 Nov;59(11):2790-8. doi: 10.2337/db10-0320. Epub 2010 Sep 7.
Physical inactivity is a risk factor for type 2 diabetes and may be more detrimental in first-degree relative (FDR) subjects, unmasking underlying defects of metabolism. Using a positive family history of type 2 diabetes as a marker of increased genetic risk, the aim of this study was to investigate the impact of physical inactivity on adipose tissue (AT) metabolism in FDR subjects.
A total of 13 FDR and 20 control (CON) subjects participated in the study. All were studied before and after 10 days of bed rest using the glucose clamp technique combined with measurements of glucose uptake, lipolysis, and lactate release from subcutaneous abdominal (SCAAT) and femoral (SCFAT) adipose tissue by the microdialysis technique. Additionally, mRNA expression of lipases was determined in biopsies from SCAAT.
Before bed rest, the FDR subjects revealed significantly increased glucose uptake in SCAAT. Furthermore, mRNA expression of lipases was significantly decreased in the SCAAT of FDR subjects. Bed rest significantly decreased lipolysis and tended to increase glucose uptake in the SCFAT of both CON and FDR subjects. In response to bed rest, SCAAT glucose uptake significantly increased in CON subjects but not in FDR subjects.
FDR subjects exhibit an abnormal AT metabolism including increased glucose uptake prior to bed rest. However, the differences between FDR and CON subjects in AT metabolism were attenuated during bed rest due to relatively more adverse changes in CON subjects compared with FDR subjects. Physical inactivity per se is not more deleterious in FDR subjects as compared with CON subjects with respect to derangements in AT metabolism.
身体活动不足是 2 型糖尿病的一个风险因素，在一级亲属（FDR）人群中可能更为不利，暴露出潜在的代谢缺陷。本研究使用 2 型糖尿病阳性家族史作为遗传风险增加的标志物，旨在研究身体活动不足对 FDR 人群脂肪组织（AT）代谢的影响。
共有 13 名 FDR 和 20 名对照（CON）受试者参与了这项研究。所有受试者在接受 10 天卧床休息之前和之后，均使用葡萄糖钳夹技术，结合微透析技术测量皮下腹部（SCAAT）和股部（SCFAT）脂肪组织的葡萄糖摄取、脂肪分解和乳酸释放情况。此外，还通过活检测量了 SCAAT 中脂肪酶的 mRNA 表达。
卧床休息前，FDR 受试者的 SCAAT 葡萄糖摄取明显增加。此外，FDR 受试者的 SCAAT 脂肪酶 mRNA 表达明显降低。卧床休息显著降低了 CON 和 FDR 受试者的脂肪分解作用，且倾向于增加 SCFAT 的葡萄糖摄取。与卧床休息相反，CON 受试者的 SCAAT 葡萄糖摄取明显增加，但 FDR 受试者则不然。
FDR 受试者表现出异常的 AT 代谢，包括卧床休息前葡萄糖摄取增加。然而，由于 CON 受试者的变化比 FDR 受试者更为不利，因此，在卧床休息期间，FDR 和 CON 受试者之间在 AT 代谢方面的差异减弱。就 AT 代谢紊乱而言，与 CON 受试者相比，身体活动不足本身对 FDR 受试者的危害性并没有更大。
