Serum/glucocorticoid-regulated kinase 1-targeted transient receptor potential oxalate subtype 1 regulates bladder smooth muscle cell proliferation due to bladder outlet obstruction in mice via activated T cell nuclear factor transcription factor 2.

Bladder outlet obstruction (BOO) is a type of chronic disease that is mainly caused by benign prostatic hyperplasia. Previous studies discovered the involvements of both serum/glucocorticoid-regulated kinase 1 (SGK1) and activated T cell nuclear factor transcription factor 2 (NFAT2) in the proliferation of smooth muscle cells after BOO. However, the relationship between these two molecules is yet to be explored. Thus, this study explored the specific mechanism of the SGK1-NFAT2 signaling pathway in mouse BOO-mediated bladder smooth muscle cell proliferation in vivo and in vitro. In vivo experiments were performed by suturing 1/2 of the external urethra of female BALB/C mice to cause BOO for 2 weeks. In vitro, mouse bladder smooth muscle cells (MBSMCs) were treated with dexamethasone (Dex) or dexamethasone + SB705498 for 12 h and were transfected with SGK1 siRNA for 48 h. The expression and distribution of SGK1, transient receptor potential oxalate subtype 1 (TRPV1), NFAT2, and proliferating cell nuclear antigen (PCNA) were measured by Western blotting, polymerase chain reaction, and immunohistochemistry. The relationship between SGK1 and TRPV1 was analyzed by coimmunoprecipitation. The proliferation of MBSMCs was examined by 5-ethynyl-2'-deoxyuridine and cell counting kit 8 assays. Bladder weight, smooth muscle thickness, and collagen deposition in mice after 2 weeks of BOO were examined. Bladder weight, smooth muscle thickness, the collagen deposition ratio, and the expression of SGK1, TRPV1, NFAT2, and PCNA were significantly increased in mice after 2 weeks of BOO. Compared with the control, 10 µM Dex promoted the expression of these four molecules and the proliferation of MBSMCs. After inhibiting TRPV1, only the expression of SGK1 was not affected, and the proliferation of MBSMCs was inhibited. After silencing SGK1, the expression of these four molecules and the proliferation of MBSMCs decreased. Coimmunoprecipitation suggested that SGK1 acted directly on TRPV1. In this study, SGK1 targeted TRPV1 to regulate the proliferation of MBSMCs mediated by BOO in mice through NFAT2 and then affected the process of bladder remodeling after BOO. This finding may provide a strategy for BOO drug target screening.

Urethral meatus stricture BOO stimulates bladder smooth muscle cell proliferation and pyroptosis via IL­1ß and the SGK1­NFAT2 signaling pathway.

Bladder outlet obstruction (BOO), which is primarily caused by benign prostatic hyperplasia, is a common chronic disease. However, previous studies have most commonly investigated BOO using the acute obstruction model. In the present study, a chronic obstruction model was established to investigate the different pathological alterations in the bladder between acute and chronic obstruction. Compared with chronic obstruction, acute obstruction led to increased expression of proliferating cell nuclear antigen and interleukin­1ß, which are markers of proliferation and inflammation, respectively. Furthermore, increased fibrosis in the bladder at week 2 was observed. Low pressure promoted mice bladder smooth muscle cell (MBSMC) proliferation, and pressure overload inhibited cell proliferation and increased the proportion of dead MBSMCs. Further investigation using serum/glucocorticoid regulated kinase 1 (SGK1) small interfering RNAs indicated that low pressure may promote MBSMC proliferation by upregulating SGK1 and nuclear factor of activated T­cell expression levels. Therefore, the present study suggested that acute obstruction led to faster decompensation of bladder function and chronic bladder obstruction displayed an enhanced ability to progress to BOO.

Laparoscopic versus Open Partial Nephrectomy: Comparison of Overall and Subgroup Outcomes.

BACKGROUND: At experienced centers, laparoscopic partial nephrectomy (LPN) can achieve similar results to those of open surgery (OPN). However, the role of LPN for complex tumors and imperative indications is under debate. PATIENTS AND METHODS: A total of 356 cases (186 LPN and 170 OPN) between 2005-2012 were reviewed. Clinical, surgical, pathological and radiological data, including PADUA classification were analyzed. RESULTS: In overall analysis, OPN was associated with higher tumor complexity (p≤0.03). Subgroup analysis of PADUA >8 tumors (n=85) showed no significant difference between LPN and OPN. In patients with unfavorable treatment characteristics (imperative indication/multifocal tumors, n=71) LPN was beneficial. In this subgroup, LPN led to better perioperative (p≤0.02) and postoperative (p≤0.04) outcome. CONCLUSION: Use of LPN is associated with favorable tumor characteristics. Although no advantage was shown for LPN for tumors with higher complexity (PADUA>8), this large series confirmed the superiority of LPN for imperative indication or multifocal tumors.