Given our observation that podocyte-specific Smpdl3b-deficient diabetic mice are protected from experimental DKD, and that kidney cortex from db/db mice are characterized by decreased C1P content (Fig. 5g), we hypothesized that exogenous supplementation of C1P may protect from albuminuria and podocyte injury in DKD. Here, SMPDL3B is linked to diabetic kidney disease.