Microdialysis Can Detect Age-Related Differences in Glucose Distribution within the Dermis and Subcutaneous Adipose Tissue

Background: Intrinsic (chronological) cutaneous aging is a continuous and complex process. Limitation in nutrient supply to the skin could contribute to this process. Objective: Our study focused on the impact of age on glucose supply to human skin and its distribution within the dermis and subcutaneous adipose tissue. Methods: An oral glucose load (100 g) was given to healthy volunteers of two age groups (24 ± 4 and 59 ± 10 years, n = 4 for each group). Dialysate concentrations of glucose and glycerol were monitored by microdialysis in the dermis and adipose tissue. Results: Baseline tissue [glucose] did not differ significantly between the two groups. After the glucose load, dialysate [glucose] of the dermis peaked between 60 and 80 min and between 80 and 120 min in the young and old groups, respectively. In the old group, dialysate [glucose] was significantly higher in the dermis than adipose tissue at 80, 100, 120, 160 and 180 min after the load. The sum of the areas under the curve (dermis + adipose tissue) did not differ significantly between the two age groups. Conclusions: Aging is accompanied by an increased diffusion barrier for glucose between the dermis and adipose tissue.