Glucose transporter-4 in mononuclear cells of sled dogs

Abstract

The glucose transporter-4 (GLUT4) is the glucose transporter most responsive to insulin and has been thought to exist predominately in muscle and adipose cells. There have been findings that the glucose transporter-4 isoform is also expressed in subpopulations of white blood cells such as mononuclear cells. This study was designed to validate the presence of GLUT4 in subpopulations of white blood cells of sled dogs and to investigate whether changes in GLUT4 protein levels in white blood cells might be associated with age and stage of conditioning, as it has been reported in muscle. Our initial results have shown the ability to detect GLUT4 in white blood cells of sled dogs with a non-significant trend observed in GLUT4 levels based on age. Subsequent testing showed a statistically significant difference in GLUT4 levels in mononuclear cells based on conditioning in sled dogs. Using sled dogs as a model should enhance our understanding of GLUT4 expression on the surface of subpopulations of white blood cells. The presented projects are groundbreaking for the development of an easy, reliable and minimally invasive diagnostic tool for insulin sensitivity. Our next step in this research is to examine whether the conditioning response of GLUT4 is also observed in human mononuclear cells.