In conclusion, this experiment reveals that rat uMDSCs can be isolated successfully and can form myotubes in vitro. PERK/ATF4 pathway was involved in myotube formation, and L6 rat myoblast cells were activated by Li-ESWT to form myotubes. These findings suggest that PERK/ATF4 pathway is activated by Li-ESWT. This study elucidates one of the biochemical pathways responsible for the clinical improvements seen after Li-ESWT. It is possible that this information will help to establish Li-ESWT as an acceptable treatment modality and may help to further refine the use of Li-ESWT in the clinical practice of medicine.

Low-intensity extracorporeal shock wave therapy (Li-ESWT) is used in the treatment of erectile dysfunction, but its mechanisms are not well understood. Previously, we found that Li-ESWT increased the expression of brain-derived neurotrophic factor (BDNF). Here we assessed the underlying signaling pathways in Schwann cells in vitro and in penis tissue in vivo after nerve injury. The result indicated that BDNF were significantly increased by the Li-ESWT after nerve injury, as well as the expression of BDNF in Schwann cells (SCs, RT4-D6P2T) in vitro. Li-ESWT activated the protein kinase RNA-like endoplasmic reticulum (ER) kinase (PERK) pathway by increasing the phosphorylation levels of PERK and eukaryotic initiation factor 2a (eIF2α), and enhanced activating transcription factor 4 (ATF4) in an energy-dependent manner. In addition, GSK2656157—an inhibitor of PERK—effectively inhibited the effect of Li-ESWT on the phosphorylation of PERK, eIF2α, and the expression of ATF4. Furthermore, silencing ATF4 dramatically attenuated the effect of Li-ESWT on the expression of BDNF, but had no effect on hypoxia-inducible factor (HIF)1α or glial cell-derived neurotrophic factor (GDNF) in Schwann cells. In conclusion, our findings shed new light on the underlying mechanisms by which Li-ESWT may stimulate the expression of BDNF through activation of PERK/ATF4 signaling pathway. This information may help to refine the use of Li-ESWT to further improve its clinical efficacy.

Kidney stones are a potential risk factor for chronic kidney disease. The impact of different urinary stone components on renal function is unknown. In this study, we retrospectively reviewed 1,918 medical records of patients with urolithiasis. The renal function was evaluated as estimated glomerular filtration rate. All the stones were analyzed by Fourier transform infrared spectroscopy. The patients were divided into five groups according to the stone components. Statistical analysis was performed with analysis of variance. All the patients with stones had Stage 2-3 chronic kidney disease. The patients with uric acid and struvite stones had significantly lower estimated glomerular filtration rate compared with those having other stone components (p<0.01). Furthermore, the patients with calcium-containing stones (calcium oxalate and calcium phosphate) had significantly better renal function than those with non-calcium-containing stones (struvite and uric acid, p<0.01). Patients with urolithiasis had decreased renal function, and the impact of renal function varied depending on the stone components. We conclude that stone analysis is important in predicting the change in renal function in patients with urolithiasis. Moreover, the patients with non-calcium-containing stones, such as struvite and uric acid stones, should be carefully evaluated and treated to preserve their renal function.

Objectives To evaluate the therapeutic effect of once-per-week low-intensity extracorporeal shock wave therapy (Li-ESWT) on underactive bladder (UAB) in the streptozotocin-induced diabetic rat model. Materials and Methods Thirty-six female Sprague-Dawley rats were assigned into 3 groups: normal control (NC), diabetes control (DMC), and diabetes underwent Li-ESWT (DM Li-ESWT). The two DM groups received intraperitoneal 60 mg/kg streptozotocin injection to induce diabetes mellitus. The Li-ESWT was applied toward the pelvis of the rats started 4 weeks after the streptozotocin administration and lasted for 4 weeks. The shock wave therapy was given once-per-week with energy flux density of 0.02 mJ/mm2 at 3 Hz for 400 pulses. All rats were subjected to conscious cystometry, leak point pressure, ex-vivo organ bath study, histology, immunofluorescence, and western blot analysis. Results Conscious cystometry revealed voiding dysfunction in DMC group, whereas DM Li-ESWT group showed significantly improved voiding function in reduced post-void residual urine and increased leak point pressure compared to DMC group. Ex-vivo organ bath study showed that Li-ESWT enhances muscle contractile activity (MCA) of bladder and urethra in electrical field stimulation (EFS) and drug stimulation. Histologically, Li-ESWT significantly restored bladder morphology in reducing intravesical lumen area and increasing muscle proportion of the bladder wall. Western blot analysis showed higher smooth muscle actin (SMA) expression of bladder wall in DM Li-ESWT compared to DMC group. Immunofluorescence showed decreased nerve-ending distribution, and destroyed and shortened nerve fibers in DMC group and recovery of neuronal integrity and innervation in DM Li-ESWT group. Conclusions In conclusion, Li-ESWT ameliorated underactive bladder and urinary incontinence in the diabetic UAB rat model. The improvement seems to be the results of restoration of bladder and urethra structure and function by Li-ESWT. Li-ESWT is non-invasive and may become a better alternative therapy for UAB. Further investigations are warranted.

ZF rats can serve as an animal model in which to study OAED. This study reveals that obesity impairs erectile function by causing smooth muscle atrophy, endothelial dysfunction, and lipid accumulation in the corpus cavernosum. Li-ESWT restored penile haemodynamic parameters in the ZF rats by restoring smooth muscle and endothelium content and reducing lipid accumulation. The underlying mechanism of Li-ESWT appears to be activation of stem/progenitor cells, which prompts cellular proliferation and accelerates penile tissue regeneration. Our findings are of interest, not just as a validation of this emerging treatment for erectile dysfunction, but also as a novel and potentially significant method to modulate endogenous stem/progenitor cells in other disease processes.

Aim Obesity is a strong independent risk factor for urinary incontinence. Effective therapeutic approaches for obesity‐associated stress urinary incontinence (OA‐SUI) are lacking as the mechanisms remain unclear. The aim of our study is to explore the impacts of microenergy acoustic pulse (MAP) therapy on urethral and pelvic floor muscle structure and function in female lean and fatty rats. Methods A total 24 Zucker fatty (ZF) and 24 Zucker lean (ZL) female 24‐week‐old rats were grouped into four groups: ZL control, ZLMAP, ZF control, and ZFMAP. For MAP treatment, 500 pulses were delivered at an energy level of 0.033 mJ/mm 2 and a frequency of 3 Hz and were applied twice a week for 4 weeks. After a 1‐week washout, all rats underwent conscious cystometry and leak‐point pressure (LPP) measurements followed by ex vivo organ‐bath assay and histological study. Results ZF rats had lower LPP as compared to ZL rats, and MAP treatment significantly improved LPP in ZF rats (P < .05). Impaired muscle contractile activity (MCA) in organ‐bath study was noted in ZF rats. MAP treatment significantly increased MCA in ZF rats (P < .05) and also increased the thickness of the striated muscle layer and the number of neuromuscular junctions (NMJs). In situ, MAP activated muscle satellite cells significantly (P < .05). Conclusions Obesity impairs the function of both the urethral sphincter and the pelvic floor and leads to atrophy and distortion of the striated muscle in obese female rats. These issues contribute to OA‐SUI. MAP improves continence by stimulating muscle regeneration and nerve innervation as well as by activating satellite cells.

Background: Stress urinary incontinence (SUI) is a common disorder with high prevalence in women across their life span, but there are no non-surgical curative options for the condition. Stem cell-based therapy, especially endogenous stem cell therapy may be a potential treatment method for SUI. The aims of this study are to identify, isolate, and assay the function of urethral striated muscle derived stem/progenitor cells (uMDSCs) and to assess uMDSC response to microenergy acoustic pulses (MAP).Methods: Urethral striated muscle was identified utilizing 3D imaging of solvent organs (3DISCO) and immunofluorescence (IF). uMDSCs were isolated and purified from Zucker Lean (ZL) (ZUC-LEAN) (ZUC-Leprfa 186) rats, with magnetic-activated cell sorting (MACS) and pre-plating methods. The stemness and differentiation potential of the uMDSCs were measured by cell proliferation, EdU, flow cytometry, IF, and Western blot.Results: Comparison of the cell proliferation assays between MACS and pre-plating reveals the advantage of MACS over pre-plating. In addition, the study reveals that uMDSCs form myotubes when treated with MAP. Conclusions:The uMDSCs within female rat urethral striated muscle could be a therapeutic target of MAP in managing SUI.

Background: Erectile dysfunction (ED) caused by pelvic neurovascular injury (PNVI) is often refractory to treatment. In many cases erectogenic therapy is administered in a delayed fashion. Aims: To evaluate penile hemodynamic effects and histological changes associated with delayed low-intensity extracorporeal shock wave therapy (Li-ESWT) after PNVI ED in a rat model. We visualized images using immunofluorescence and 3-dimensional imaging of solvent cleared organs (3DISCO), a novel imaging technique. Methods: 32 Sprague-Dawley male rats aged 12 weeks-old were divided equally into four groups: sham surgery as normal controls (NC), PNVI controls (PC), PNVI with very-low-energy Li-ESWT (PVL), and PNVI with low-energy Li-ESWT (PL) group. Bilateral cavernous nerve (CN) crush and internal pudendal bundle (IPB) ligation were performed in the PNVI groups. Li-ESWT was administered twice a week for four weeks in the PL and PVL groups starting 4 weeks after PNVI. Outcomes: Intracavernous pressure (ICP) studies (normalized to Mean Arterial Pressure, MAP) were conducted in all subject animals. After testing, tissue was harvested for immunofluorescence staining and 3DISCO. Results: Mean ICP/MAP was lower in PC compared to NC animals (0.37 ± 0.03 vs 0.91 ± 0.03, respectively, p=0.001). The ICP/MAP ratio was significantly higher in PVL and PL animals (0.66 ± 0.07 and 0.82 ± 0.05, respectively) compared to PC animals (p=0.002 and 0.001, respectively). Detailed microstructures and trajectories of nerves and vessels were identified with immunofluorescence and 3DISCO. The PC group had lower density of nerves, axons, nNOS positive nerves, and Schwann cells in the dorsal penis. Animals in the PL group had significantly higher expression of all of these markers compared to PC animals. Clinical Implications: Li-EWST may have utility in the management of severe ED related to PNVI from severe pelvic injury or radical pelvic surgeries, even when administered in a delayed fashion. Strengths and Limitations: This study of a severe ED phenotype involved treatment administered in a delayed fashion, which is more consistent with how therapy would likely be delivered in a real world clinical context. Moreover, since the treatment commenced 4 weeks after injury when nerve and tissue atrophy have already occurred, the results imply that Li-ESWT can be used for regenerative therapy. Additional studies on dose optimization and treatment interval are required to inform the design of human clinical trials Conclusions: Li-ESWT ameliorates the negative functional and histological effects of severe pelvic neurovascular injury in a rat model system. 3DISCO provided high-resolution images of neuroanatomy and neural regeneration.