SRGAP2a: A New Player That Modulates Podocyte Cytoskeleton and Injury in Diabetes

Podocyte injury and podocyte loss are common features in diabetic kidney disease (DKD). Podocyte detachment and decreased podocyte numbers occur in patients with type 1 or type 2 diabetes and correlate with the progression of renal disease (1–5). Podocytes play a critical role in the maintenance of the glomerular tuft and the filtration barrier. Foot processes of adjacent podocytes interdigitate to form narrow filtration slits that are bridged by the slit diaphragm (6–9). Podocyte foot processes form the final barrier to protein loss by creating the porous membrane slit diaphragm. Progressive injury and loss of podocytes result in loss of protein in the urine. The resulting microalbuminuria can progress to macroalbuminuria, glomerulosclerosis, and progressive loss of glomerular filtration rate that are hallmarks of DKD (10,11). The actin …