Fig 1. SPL treatment prevents diabetes-induced glomerular and tubular damage.

(A) Schematic representation of the experimental strategy used in this study. Four groups of rats were studied: Control (CTL), Diabetic (DBT), DBT+SPL and SPL, respectively (for detail see Material and methods). (B) Purity of isolated glomerular and proximal tubular segments was evaluated by IB analysis of Wilm´s tumor 1 (WT1) and dipeptidylpeptidase (DppD) expressions, respectively. (C) IB analysis of nephrin and WT1 shows that SPL treatment prevents diabetes-induced glomerular damage; densitometric analysis of nephrin (D) and WT1 (E) are shown (S1 Fig). (F) IB analysis of kidney injury molecule 1 (Kim)-1 and heat shock protein of 72 KDa (Hsp72) show that SPL treatment decreases diabetes-induced proximal tubular damage, densitometric analysis of Kim-1 (G) and Hsp72 (H) are shown (S1 Fig). No changes were found in SPL group compared to CTL group. (I) IF analysis confirms that SPL treatment decreases diabetes-induced Kim-1 expression (green label) in PT labeled with DppD (red label). Nuclei were marked with 4', 6-diamidino- 2-phenylindole (DAPI, blue label). No significant changes were found between SPL and CTL groups. Glyceraldehyde 3-phosphate dehydrogenase (GAPDH) was used as loading control for IB. Data are mean±SEM from 3 rats per group. *p<0.05; **p<0.01 and ***p<0.001. Images are representative of three different experiments performed in the four experimental groups. Bar = 50 μm.