Transcription Factor ß-Catenin Plays a Key Role in Fluid Flow Shear Stress-Mediated Glomerular Injury in Solitary Kidney.

Increased fluid flow shear stress (FFSS) in solitary kidney alters podocyte function in vivo. FFSS-treated cultured podocytes show upregulated AKT-GSK3ß-ß-catenin signaling. The present study was undertaken to confirm (i) the activation of ß-catenin signaling in podocytes in vivo using unilaterally nephrectomized (UNX) TOPGAL mice with the ß-galactosidase reporter gene for ß-catenin activation, (ii) ß-catenin translocation in FFSS-treated mouse podocytes, and (iii) ß-catenin signaling using publicly available data from UNX mice. The UNX of TOPGAL mice resulted in glomerular hypertrophy and increased the mesangial matrix consistent with hemodynamic adaptation. Uninephrectomized TOPGAL mice showed an increased ß-galactosidase expression at 4 weeks but not at 12 weeks, as assessed using immunofluorescence microscopy (p < 0.001 at 4 weeks; p = 0.16 at 12 weeks) and X-gal staining (p = 0.008 at 4 weeks; p = 0.65 at 12 weeks). Immunofluorescence microscopy showed a significant increase in phospho-ß-catenin (Ser552, p = 0.005) at 4 weeks but not at 12 weeks (p = 0.935) following UNX, and the levels of phospho-ß-catenin (Ser675) did not change. In vitro FFSS caused a sustained increase in the nuclear translocation of phospho-ß-catenin (Ser552) but not phospho-ß-catenin (Ser675) in podocytes. The bioinformatic analysis of the GEO dataset, #GSE53996, also identified ß-catenin as a key upstream regulator. We conclude that transcription factor ß-catenin mediates FFSS-induced podocyte (glomerular) injury in solitary kidney.

Long-term outcomes of ultrasound-guided percutaneous nephrolithotomy in patients with solitary kidneys: a single-center experience.

PURPOSE: To report our experience with total ultrasound-guided percutaneous nephrolithotomy (PCNL) in the management of patients with solitary kidney, and evaluate the safety and feasibility of this technique. MATERIALS AND METHODS: Between October 2014 and December 2016, 48 patients with solitary kidneys underwent total ultrasound-guided PCNL at our institution. Stone-free rate (SFR), auxiliary procedures, and complications were recorded. Changes in renal function were evaluated by comparing preoperative and postoperative estimated glomerular filtration rates (eGFRs). Perioperative factors that may affect renal function were analyzed to define factors predicting renal function improvement on long-term follow-up. Of 48 patients, 44 were followed at least 6 months, whereas four patients were lost to follow-up. RESULTS: Among all patients, staghorn calculi were found in 18 (37.5%) patients. 14 (29.2%) patients required a two-stage PCNL. Struvite was found in six (12.5%) patients. Complications were reported in eight (16.7%) patients. Severe bleeding was noticed in three patients; no angioembolization was required. After a median follow-up of 12 (6-26) months, the final SFR was 81.8% after auxiliary treatments. There was a significant improvement of eGFR from 53.9 ± 24.0 to 61.3 ± 25.4 mL/min/1.73 m2 (P < 0.01). Renal function was stable, improved and worse in 65.9% (n = 29), 27.3% (n = 12), and 6.8% (n = 3) of patients, respectively, compared with preoperative levels. CONCLUSIONS: Ultrasound-guided PCNL is a safe and feasible procedure with an acceptably low complication rate in patients with solitary kidneys. At long-term follow-up, the renal function in more than 90% of the patients with solitary kidneys can be improved or stabilized after ultrasound-guided PCNL.