The Piezo channel family, including Piezo1 and Piezo2, includes essential mechanosensitive transduction molecules in mammals. Functioning in the conversion of mechanical signals to biological signals to regulate a plethora of physiological processes, Piezo channels, which have a unique homotrimeric three-blade propeller-shaped structure, utilize a cap-motion and plug-and-latch mechanism to gate their ion-conducting pathways. Piezo channels have a wide range of biological roles in various human systems, both in vitro and in vivo. Currently, there is a lack of comprehensive understanding of their antagonists and agonists, and therefore further investigation is needed. Remarkably, increasingly compelling evidence demonstrates that Piezo channel function in the urinary system is important. This review article systematically summarizes the existing evidence of the importance of Piezo channels, including protein structure, mechanogating mechanisms, and pharmacological characteristics, with a particular focus on their physiological and pathophysiological roles in the urinary system. Collectively, this review aims to provide a direction for future clinical applications in urinary system diseases.

Background: Polycystic ovary syndrome (PCOS) is characterized by hyperandrogenism, anovulation, and polycystic ovaries. Electroacupuncture (EA) can effectively improve hyperandrogenism and increase ovulation frequency in patients with PCOS. Pieces of suggest that androgen activity in the brain is associated with impaired steroid negative feedback in such patients. Studies have shown that EA regulated androgen receptor (AR) expression and local factor levels (such as anti-Müllerian hormone and inhibin B) in the ovary of PCOS rats. However, few studies have explored the effect of EA on androgen activity in the brain. Objective: This study investigated the effect of EA on the kisspeptin-gonadotropin-releasing hormone (GnRH)/luteinizing hormone (LH) neural circuit and sex hormone receptor expression in the hypothalamus of PCOS rats. Methods: PCOS signs were induced by letrozole administration, and the induced rats were treated with low-frequency EA at Guan Yuan acupoint (CV4). The effect of EA on PCOS-like signs was evaluated by observing changes in the body weight, ovarian quality, ovarian morphology, and serum sex hormone levels in rats. To explore the mechanism of the effect of EA on PCOS-like signs, the neuropeptide content of the kisspeptin-GnRH/LH neural circuit was assessed using enzyme-linked immunosorbent assay(ELISA); AR and estrogen receptor α (ERα) coexpression on kisspeptin/neurokinin B/dynorphin (KNDy) neurons was determined via triple-label immunofluorescence; and protein and mRNA expression of Kiss1, Ar, Esr1, and kisspeptin receptor (Kiss1r) was evaluated via western blotting and Reverse Transcription-Polymerase Chain Reaction (RT-PCR). Results: The results revealed that the estrous cycle of rats in the EA treatment group recovered, and their body and ovary weight reduced; ovarian morphology improved; serum testosterone and LH levels significantly decreased; and kisspeptin, GnRH, and dynorphin levels in hypothalamic arcuate nucleus significantly decreased. Compared with controls, the number of AR/Kiss1-positive cells increased, number of ERα/Kiss1-positive cells decreased, and protein and mRNA expression of Kiss1, Ar, and Kiss1r significantly increased in PCOS rats. However, EA treatment reversed these changes and reduced the expression of Kiss1, Ar, and Kiss1r significantly. Conclusion: Improvement in the reproductive hallmarks of PCOS rats via EA may be achieved by regulating the kisspeptin-GnRH/LH circuit via androgen activity attenuation. Thus, the results provide an experimental basis for acupuncture as an adjuvant medical therapy on PCOS.

Pelvic floor muscle training (PFMT) is a first-line conservative therapy for stress urinary incontinence (SUI). Electroacupuncture (EA) has been used to treat SUI recently. To compare the effectiveness of PFMT + EA versus PFMT + sham EA for SUI in women. A prospective, multicenter, randomized, controlled clinical trial was conducted at four hospitals in China involving 304 women with SUI from May 20, 2014 to November 21, 2017. Data were analyzed from April 20 to December 21, 2018. Participants were randomized to receive 8 wk of PFMT+ EA (n = 154) or PFMT + sham EA (n = 150). The primary outcome was the change in the amount of urine leakage measured on a 1-hr pad test. Student's t test, the χ² test, and the Wilcoxon rank-sum test were used for data analysis. Among the 304 participants randomized, 286 completed the study. The mean age was 57.6 yr (standard deviation [SD] 8.9) for the PFMT + sham EA group and 57.2 yr (SD 9.1) for the PFMT + EA group. The mean urine leakage at baseline was 13.6 g for the PFMT + sham EA group and 13.9 g for the PFMT + EA group. After the 8-wk intervention, the PFMT + EA group had a greater decrease in mean urine leakage (-9.8 g) than the PFMT + sham EA group (-5.8 g) with a mean difference of 4.0 g (95% confidence interval [CI] 0.8-7.2). Significantly more patients experienced a ≥50% reduction in urine leakage and the mean number of incontinence episodes in 24 h in the PFMT + EA group than in the PFMT + sham EA group (26.3%, 95%CI 15.8-36.8%). The PFMT + EA group experienced better improvement in participant-reported SUI severity at 6 wk (p < 0.001) and 8 wk (p < 0.001) and self-evaluated therapeutic effects at 2-32 wk (p < 0.001) after the intervention. Lack of measurement of the amount of urine leakage during follow-up is a limitation. In this randomized clinical trial, 8-wk combined treatment with PFMT + EA led to a greater improvement in SUI symptoms and better outcomes than with PFMT + sham EA. We evaluated the effectiveness and safety of pelvic floor muscle training combined with electroacupuncture for stress urinary incontinence in women, Our results show that this is a promising therapeutic approach for the treatment of stress urinary incontinence.

Introduction and hypothesis: To examine the changes induced by electroacupuncture in stress urinary incontinence (SUI) rats, including the urodynamics and collagen degradation-related cytokine molecular biological expression changes, and to explore the effect and mechanism of EA treatment in SUI. Methods: Female SPF Sprague-Dawley rats were randomly assigned to five groups (n = 10): sham, model, electroacupuncture control, electroacupuncture, and blocker. The leak point pressure (LPP) and maximum bladder capacity (MBC) were measured for each group of rats, and collagen I, collagen III, matrix metalloproteinases (MMPs), and tissue inhibitor of metalloproteinase (TIMPs) in the anterior vaginal wall of rats in each group were determined by reverse transcription-polymerase chain reaction and western blotting. The data were analyzed by one-way analysis of variance or Kruskal-Wallis test. Results: Electroacupuncture Shenshu (BL23) and Huiyang (BL35) increased the LPP and MBC in SUI rats (P < 0.05). Electroacupuncture treatment significantly increased the protein expression of collagen I and collagen III in the anterior vaginal wall of SUI rats (P < 0.05) and significantly reduced the protein expression of MMP1, MMP2, and MMP9 (P < 0.05). Conclusions: Electroacupuncture stimulation can alleviate the signs of SUI, and its mechanism is related to the degradation of collagen in the anterior vaginal wall.

The urothelium, which covers the inner surface of the bladder, is continuously exposed to a complex physical environment where it is stimulated by, and responds to, a wide range of mechanical cues. Mechanically activated ion channels endow the urothelium with functioning in the conversion of mechanical stimuli into biochemical events that influence the surface of the urothelium itself as well as suburothelial tissues, including afferent nerve fibres, interstitial cells of Cajal and detrusor smooth muscle cells, to ensure normal urinary function during the cycle of filling and voiding. However, under prolonged and abnormal loading conditions, the urothelial sensory system can become maladaptive, leading to the development of bladder dysfunction. In this review, we summarize developments in the understanding of urothelial mechanotransduction from two perspectives: first, with regard to the functions of urothelial mechanotransduction, particularly stretch-mediated ATP signalling and the regulation of urothelial surface area; and secondly, with regard to the mechanoreceptors present in the urothelium, primarily transient receptor potential channels and mechanosensitive Piezo channels, and the potential pathophysiological role of these channels in the bladder. A more thorough understanding of urothelial mechanotransduction function may inspire the development of new therapeutic strategies for lower urinary tract diseases.

Background. Polycystic ovarian syndrome (PCOS) occurs in women of reproductive age and is often characterized by reproductive and endocrine dysfunction. Androgens play a major role in PCOS, and previous studies reported abnormal expression of Connexin 43 (Cx43) in animal models of PCOS, suggesting an association of Cx43 with PCOS pathogenesis. Experimental and clinical evidence indicated that acupuncture may be a safe and effective approach for treating reproductive and endocrine disorders in women with PCOS. This study aimed to determine the effects of electroacupuncture (EA) on PCOS and its relationship with the expression of the androgen receptor (AR) and Cx43. Methods. In total, 30 female Sprague Dawley rats (6 weeks old) were randomly divided into three groups: control group, letrozole (LE) group, and LE + EA group. Rats were administered LE solution (1.0 mg/kg) for 21 consecutive days to induce PCOS. For the LE + EA group, additional EA treatment was conducted (2 Hz, 20 min/d) with “Guanyuan” (CV3) for 14 consecutive days. After hematoxylin‐eosin staining, the ovarian structure was observed with an optical microscope, and serum levels of the following hormones were examined via enzyme‐linked immunosorbent assay (ELISA): testosterone (T), estradiol (E₂), sex hormone‐binding globulin (SHBG), follicle‐stimulating hormone (FSH); luteinizing hormone (LH), insulin (INS), anti‐Müllerian hormone (AMH), and inhibin B (INHB). Fasting blood glucose (FBG) levels were evaluated using glucose oxidase‐peroxidase. Ovarian mRNA and protein expressions of AR and Cx43 were determined by real‐time RT‐PCR and Western blot analysis. Results. EA was found to restore the cyclicity and ovarian morphology in the PCOS rat model. Serum derived from the LE + EA group showed significant decreases in the levels of T, free androgen index (FAI), LH, LH/FSH ratio, AMH, INHB, and fasting serum insulin (FINS), and significant increases in the levels of E₂, FSH, and SHBG. Western blot analysis showed a decreased protein expression of ovarian AR and Cx43; real‐time RT‐PCR showed reduced expression of ovarian mRNA levels of AR and Cx43. Conclusions. In conclusion, our results showed that EA can ease hyperandrogenism and polycystic ovary morphology in PCOS rats. Furthermore, EA counteracted the letrozole‐induced upregulation of AR and Cx43. These results suggested that acupuncture can break the vicious cycle initiated by excessive androgen secretion and may be an effective treatment method for improving the reproductive and endocrine dysfunction caused by PCOS.