In contrast to animal models of diabetic CKD9,29 and kidney cell lines exposed to high glucose concentrations30 the TGFβ/SMAD2/3 pathway which is a hallmark of renal fibrosis was not directly modulated by linagliptin in the non-diabetic 5/6 Nx model. The gene discussed is TGFB1; the disease is renal fibrosis.