Glucose concentrations in blood and tissue - a pilot study on variable time lag

Abstract

Aim. The aim of this pilot study was to acquire insight into the parameters of glycaemic control, especially, (1) the time delay (lag phase) between plasma and tissue glucose concentrations in relation to rise and fall in glucose levels and (2) the rate of glucose increase and decrease. Methods. Four healthy people (HP), 4 people with type 1diabetes (DM1) and 4 with type 2 diabetes (DM2) underwent concurrent glucose measurements by means of (1) the continuous glucose monitoring system (CGMS-Medtronic), Medtronic-Minimed, CA, USA, calibrated by the glucometer Calla, Wellion, Austria, and, (2) the Beckman II analyser to measure glucose concentrations in venous plasma. Samples were taken on 4 consecutive days in the fasting state and 4 times after consumption of 50 g glucose. Carelink Personal, MS Excel, Maple and Mat lab were applied to plot the evolution of glucose concentration and analyse the results. The time difference between increase and decrease was calculated for HP, DM 1 and DM 2. Results. In DM1and DM2, glucose tolerance testing (GTT) resulted in slower transport of glucose into subcutaneous tissue than in HP where the lag phase lasted up to 12 min. The maximum increase/decrease rates in DM1 and DM2 vs HP were 0.25 vs < 0.1 mmol/L/min. Conclusion. CGMS is shown to provide reliable plasma glucose concentrations provided the system is calibrated during a steady state. The analysis of glucose change rates improves understanding of metabolic processes better than standard GTT.

In-depth correlation analysis between tear glucose and blood glucose using a wireless smart contact lens

“…In other words, the glucose diffusion rate from blood to tears may vary among individuals but can be a unique and lasting feature for each individual over a certain period, by reflecting the individual's health condition. Such variations of lag time among individuals were also observed between ISF glucose and BG [68][69][70] , supporting our findings. Thus, further research could be followed in the future for a better understanding of the lag time between TG and BG over an extended period with a larger scale of human participants.…”

Tissue-resident NK cells differ in their expression profile of the nutrient transporters Glut1, CD98 and CD71

“…On the other hand, NK cells derived from tissues, especially CD56 bright NK cells, did not express similar levels of Glut1 after stimulation, suggesting that these tissue-resident NK cells might be less dependent on the ability to upregulate their glucose uptake upon activation and instead use other metabolites. In peripheral blood, glucose levels are usually maintained at a high level [ 53 ], enabling peripheral blood NK cells to rely in their metabolism on glucose when needed. NK cells from tissues on the other hand are more likely to encounter situations in which glucose might not be readily available [ 53 , 54 ], resulting in metabolic challenges that could impair NK cell functions.…”

“…In peripheral blood, glucose levels are usually maintained at a high level [ 53 ], enabling peripheral blood NK cells to rely in their metabolism on glucose when needed. NK cells from tissues on the other hand are more likely to encounter situations in which glucose might not be readily available [ 53 , 54 ], resulting in metabolic challenges that could impair NK cell functions. Tissue-resident NK cells therefore might be already adapted to conditions in which glucose is rare by using other nutrients than glucose in order to maintain their anti-viral and anti-tumor activity.…”

Evaluation of a New Noninvasive Glucose Monitoring Device by Means of Standardized Meal Experiments

“…24 This lag time has been described to last from less than 10 minutes to more than 45 minutes based on the diabetes stage, and in particular also related to the severity of secondary microcirculation disorders. 25-27 This fact explains why NI glucose monitoring methods are considered to be of limited efficacy in emergency situations. 14 However, the observed MARD of 14.5% for the NI CoG method indicates an acceptable performance of the NI technology during the meal study experiments.…”