Diabetic db/db mice develop glomerular fibrosis, which is prevented in DIAVIT treated db/db mice.

A) Periodic Acid Schiff (PAS) staining indicated structural abnormalities in db/db glomeruli, including mesangial matrix expansion and the presence of vacuoles (scale bar 40 μm). These appeared to be less frequent in DIAVIT-treated db/db glomeruli. Trichrome blue staining showed an increase in fibrosis (blue collagen staining) in the db/db kidney cortex, which was lower in the DIAVIT-treated db/db kidneys (scale bar 40 μm). More specifically, immunofluorescence for collagen IV and fibronectin showed an increase in glomerular fibrosis in db/db mice, compared to lean controls, which was prevented by DIAVIT treatment of the diabetic mice (quantified in B; *pC) Western blotting of protein from the kidney cortex confirms an increase in the protein expression of collagen IV and fibronectin in db/db mice, which is prevented with DIAVIT treatment. Analysis of the Western blots is summarised in D and E (*p<0.05 lean vs db/db; †p<0.05 db/db vs db/db + DIAVIT; n = 3–4 mice; One-way ANOVA with Bonferroni post-hoc test for comparison between pairs).