PPARγ agonists regulate megalin expression in vivo in mice.
BALB/c mice (n = 4–6/per group) received rosiglitazone (20 mg/kg/day) or vehicle for 10 days. (a) Kidney extracts were used to determine megalin protein levels. β-tubulin was used as loading control. (b) The bands in the blots were quantified by densitometry, and the results were plotted as the ratio of megalin/β-tubulin for each condition. (c) Immunohistochemical staining of megalin in kidney sections (cortex) showing increased immunostaining for megalin in rosiglitazone-treated mice compared to control mice. Renal tissue was immunostained using an antibody that detects the megalin cytoplasmic domain. Bar = 100 µm. (d) The megalin-immunostained area was significantly increased in the rosiglitazone group compared to the control group as measured by morphometric analysis. The graph shows the quantification of the megalin-stained area in µm2. (e) Megalin mRNA levels were determined by qPCR. Data are expressed as means ± SD. *P<0.05 vs. control, **P<0.0001 vs. control.