Periodic acid-Schiff (PAS) and immunohistochemical (IHC) staining of kidney tissues of STZ-induced diabetic mice. Representative photomicrographs of (a–d) PAS-stained kidney tissue; (e–h) immunohistochemical analysis of advanced glycation end-products (AGEs); and (i–l) methylglyoxal (MGO) in kidney sections from mice. The images shown are representative (a,e,i) normal; (b,f,j) STZ-induced diabetic; (c,g,k) aminoguanidine-treated diabetic; and (d,h,l) Eucommia ulmoides Oliv. (EU)-treated diabetic mouse kidney tissues. The histological sections stained with PAS and analyzed using IHC are presented at 400× magnification.