Fig. 6.
Podocyte-specific knockout of ocrl1 in mice (Pod-OCRL1-KO) resulted in renal pathological changes. A, Podocyte-specific knockout of ocrl1 was achieved in mice (Pod-ocrl1-KO) using the Cre-LoxP recombination system. ocrl1 and Pod-Cre genotypes were confirmed via tail genotyping, which was performed at 2 weeks of age (n = 9). B, Western blot analysis was carried out to determine the expression of ocrl1 in control and conditional knockout (cKO) glomerular podocytes. The results showed decreased expression of ocrl1 in primary glomerular cell cultures from both control mice and Pod-ocrl1-KO mice (n = 3). C, Representative images of kidneys from control and Pod-ocrl1-KO mice at 12, 16, and 20 weeks of age. D, No significant differences were observed in body weight between Pod-ocrl1-KO mice (n = 10) and control mice (n = 10). E, Coomassie blue-stained SDS-PAGE was performed on urine samples obtained from 10-week-old and 12-week-old mice, followed by densitometry quantification of albumin levels (n = 3). Additionally, 2.5, 5, and 7.5 μg of BSA were loaded as the positive control (first three lanes; molecular weight, 66.5 kDa; arrowhead). Urinary albumin excretion was quantified in control and Pod-ocrl1-KO mice at different ages (n = 10). F, Representative images of kidney sections stained with haematoxylin and eosin are shown for control and Pod-ocrl1-KO mice. Glomerular fibrosis (indicated by arrowheads) was observed in the kidneys of cKO mice at 5 months of age when stained with haematoxylin and eosin. Scale bar: 50 μm. G, Representative images obtained through transmission electron microscopy at different ages in mice. I, J, Quantification was performed to determine the mean foot process width and the number of foot processes in Pod-ocrl1-KO mice at 3, 4, and 5 months of age. ocrl1flox/flox/Cre(−) and ocrl1.+/+/Cre(+) mice were used as controls. Scale bar: 5 μm. *P < 0.05; †P < 0.01; ‡P < 0.001