In a rat model of type 1 diabetes in which serum DPP-4 levels were elevated, linagliptin reduced levels of advanced glycation end products (AGEs) and their receptor (RAGE), as well as reducing albuminuria, lymphocyte infiltration into glomeruli, and 8-hydroxy-2′-deoxyguanosine levels in the kidney, a marker of renal oxidative stress. The gene discussed is DPP4; the disease is type 1 diabetes mellitus.