The difference between steroid diabetes mellitus and type 2 diabetes mellitus: A whole-body 18F-FDG PET/CT study

Abstract

Background Steroid diabetes mellitus (SDM) is a metabolic syndrome caused by an increase in glucocorticoids, and its pathogenesis is unclear. 18F-FDG PET/CT can reflect the glucose metabolism of tissues and organs under living conditions, and plays an important role in diabetes research. Here, PET/CT imaging of SDM and type 2 diabetes mellitus (T2DM) rats was used to observe the changes of glucose metabolism in major glucose metabolism organs and immunohistochemical analysis to explore the possible pathogenesis of SDM. Results The SDM rat model was successfully established, which showed increased FBG and insulin levels; 18F-FDG PET/CT imaging showed increased FDG uptake in skeletal muscle, but no significant increase in liver uptake (15d);Immunohistochemistry showed that islet α-cell and β-cell proliferation, GLUT-4 and IRS-1, PI3Kp85α expression in skeletal muscle increased, and glycogen storage in liver and skeletal muscle increased.T2DM rats showed atrophy of pancreatic islet β cells and decreased insulin levels; Significantly reduced FDG uptake and glycogen storage in skeletal muscle and liver; IRS-1 expression in skeletal muscle decreased, and GLUT-4 and PI3Kp85α did not change significantly. Conclusion The pathogenesis of SDM is different from that of T2DM. The increased glucose metabolism of skeletal muscle may be related to the increased compensatory secretion of insulin; glucocorticoids promote the proliferation of islet α cells and cause the increase of gluconeogenesis in the liver may be the cause of its increased blood glucose.