Akt1 Deficient Mice Show Resistance to DSS-Colitis Induced Leak of Albumin-Based Contrast Media from the Colon Vasculature

Katrien Vandoorne¹, Tegest Aychek², Hagit Dafni¹, Brian A. Hemmings³, Steffen Jung², Michal Neeman¹

The etiology of inflammatory bowel disease (IBD), a group of inflammatory conditions of the intestinal tract, remains largely unknown. Akt1, a protein kinase, is a major mediator of angiogenic signaling, acting downstream of vascular endothelial growth factor (VEGF). In this study, we reported significantly decreased permeability (PS) in Akt1 deficient mice using macromolecular DCE-MRI, validated by histology. This decreased permeability of albumine-based contrast agent implies less leakage of plasma proteins and thus, limited disease progression. These results provide direct evidence that Akt1 enhances DSS-induced colitis. MRI proved to provide high sensitivity for in vivo detection of reduced permeability in colitis.