Fig. 1. MyD88 is activated in renal tubular epithelial cells in diabetes.

a Diabetes was induced in mice by streptozotocin. Kidney tissues were harvested at 16 weeks following the onset of diabetes. Representative blots show levels of MyD88 in kidney samples. GAPDH was used as loading control. Densitometric quantification was performed by ImageJ (mean ± SEM; n = 5 per group; ns not significant). b Immunoblotting showing MyD88 and TLR4 complex formation in kidney samples from diabetic mice. Samples were immunoprecipitated using TLR4 antibody and MyD88 was detected. Lower panel showing densitometric quantification (mean ± SEM; n = 5; *P < 0.05 compared to non-diabetic control mice). c Immunofluorescence double-staining of mouse kidney tissues for MyD88 (green), aquaporin-1 (AQP-1; red) and Wilms tumor-1 (WT1; red). Tissues were counterstained with DAPI (blue). Representative images shown (n = 5; scale bar = 200 µm). d Rat tubular epithelial cells NRK-52E were exposed to 33 mM glucose (HG) for indicated time periods ranging from 0 to 60 min. Lysates were immunoprecipitated using TLR4 antibody and probed for MyD88. Representative blots were shown (n = 3 independent experiments). e NRK-52E cells were transfected with Flag-MyD88 and HA-MyD88 plasmids. Cells were then exposed to HG for 0–30 min. Lysates were immunoprecipitated with HA antibody and probed for Flag epitope. Representative blots are shown (n = 3 independent experiments).