Objective: Physical inactivity is a risk factor for type 2 diabetes (T2D) and may be more detrimental in first degree relative (FDR) subjects unmasking underlying defects of metabolism. Using a positive family history of T2D 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.
Research design and methods: 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 (BR) 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.
Results: Before BR FDR subjects revealed significantly increased glucose uptake in SCAAT. Furthermore, mRNA expression of lipases was significantly decreased in SCAAT of FDR subjects. BR significantly decreased lipolysis and tended to increase glucose uptake in SCFAT of both CON and FDR. In response to BR SCAAT glucose uptake significantly increased in CON but not in FDR.
Conclusion: FDR subjects exhibit an abnormal adipose tissue metabolism including increased glucose uptake prior to BR. However, the differences between FDR and CON subjects in AT metabolism were attenuated during BR due to relatively more adverse changes in CON compared with FDR subjects. Physical inactivity per se is not more deleterious in FDR as compared with CON with respect to derangements in adipose tissue metabolism.
- Received March 4, 2010.
- Accepted August 30, 2010.
- Copyright © American Diabetes Association