Figure 5. Effect of carnosine on glomerular podocytes, glomerular ultrastructure and mesangial matrix expansion.

(A) Representative images of glomeruli immunostained for WT1 (and counterstained with hematoxylin) to visualize podocytes (brown) in wt/ob, ob/ob and ob/ob carnosine-supplemented mice. Podocyte loss observed in ob/ob mice was not prevented by carnosine treatment (quantification now shown). (B) Representative electron micrographs (30.000x) of glomeruli from ob/ob and ob/ob carnosine-supplemented mice. Untreated mice showed complete podocyte effacement (stars), GBM thickening and swelling of glomerular endothelial cells with loss of fenestrae (double arrows). Carnosine-treated mice displayed a normal capillary wall structure with intact podocyte foot processes, slit diaphragms (arrows) and endothelial fenestrae (arrowheads). FP: foot process; GBM: glomerular basement membrane; US: urinary space; CL: capillary lumen; Car: carnosine.