Location: Diet, Genomics and Immunology LaboratoryTitle: Effect of subcutaneous glucose sensor implantation on skin mRNA expression in pigs) Author
Submitted to: Diabetes Technology & Theraputics
Publication Type: Peer reviewed journal
Publication Acceptance Date: 6/5/2010
Publication Date: 8/4/2010
Citation: Kvist, P.H., Iburg, T., Dawson, H.D., Jensen, H.E. 2010. Effect of subcutaneous glucose sensor implantation on skin mRNA expression in pigs. Diabetes Technology & Theraputics. 10:791-799. Interpretive Summary: Pigs are similar to humans in terms of organ size, digestive physiology, coronary vasculature, social behaviors, dietary habits, and propensity to obesity. In this study, pigs were used to evaluate sensors routinely implanted under the skin of humans for continuous glucose measurements. Previous studies suggested that measurements from these devices are inaccurate and unstable because of host incompatibility and a progressive inflammatory response that limited the number of days that data can reliably be obtained from the sensor. This study provides a quantitative measurement of inflammation in the skin at the molecular level. The results showed a broad category of genes involved in immunity and inflammation that were increased from 24 hours to seven days after implantation. Understanding the mechanism involved in gene activation will provide an important model to construct glucose sensors with materials that are host-compatible, resulting in a longer lifespan and reduced inflammation. This work furthers the use of the pig as a model for human diabetes and obesity research, and provides useful information for those interested in the control of diabetes and metabolic syndrome.
Technical Abstract: Tight glycemic control has the potential to reduce long- and short-term effects of diabetes mellitus. Glucose sensors for short-term implantation in subcutis offer an alternative to the classical, self-monitored blood glucose concentration in the management of diabetes. However, instability of in-vivo glucose sensor measurements, partly due to inflammation around the sensor, has been reported. Here, tissue was sampled around a glucose sensor at different time points after implantation in the subcutis of pigs. Real-time PCR analysis was performed on RNA extracted from the subcutis. Genes coding for adhesion molecules, chemokines, cytokines, CD markers, and antigen presentation molecules were differentially expressed over time. The majority of genes were significantly up-regulated 24 hours and 7 days after implantation and the inflammatory reaction involved elements of innate and adaptive immunity.