Figure 5. Tubular deletion of FoxO3 (FoxO3^tub) during the AKI-to-CKD transition results in focal glomerular sclerosis.

Tubular FoxO3 was deleted from day 8 to day 21 following a 35-minute left kidney IRI and right nephrectomy, and kidneys were analyzed 4 weeks after IRI. (A) PAS staining indicated no increases in glomerular cellularity, and Silver staining showed mild thickening of the basement membrane in Bowman’s capsule but no changes in the basement membrane of capillary loops in the glomeruli of FoxO3^tub or FoxO3^ctl mice. EM analysis showed rare podocyte foot process effacement, although more mesangial deposits were observed in FoxO3^tub kidneys. (B) Immunostaining of podocytes with P57 (red) showed that in FoxO3^tub and FoxO3^ctl mice, there were no significant changes in the number of podocytes per glomerulus after IRI. Top panel: Endomucin (green) labeled glomerular capillary loops. Bottom panel: Vimentin (red) and endomucin (green) staining showed focal glomerular sclerosis with vimentin deposition and loss of capillary loops in FoxO3^tub mice. n = 4. Scale bars: 50 μm (A, top and middle panels), 10 μm (B), and 5 μm (A, bottom panel).