Continuous administration of mirabegron has advantages in inhibition of central sensitization compared with short-term treatment cessation in a mouse model of overactive bladder.

AIMS: There is no clear pathophysiologic evidence determining how long overactive bladder (OAB) medication should be continued. We, therefore, investigated the effect of mirabegron using cessation (CES) or continuation (CON) treatment in an OAB animal model. METHODS: Female C57BL/6 mice were divided into four groups (N = 8 each): Sham, OAB, CES, and CON groups. The OAB-like condition was induced by three times weekly intravesical instillations of KCl mixture with hyaluronidase. After the last intravesical instillation for inducing OAB, mirabegron (2 mg/kg/day) was administered in CES and CON groups for 10 and 20 days, respectively. Final experiments were carried out on 20 days from the last intravesical instillation in all groups. After cystometry, mRNA levels of bladder muscarinic, ß-adrenergic, and P2X purinergic receptors were measured to investigate bladder efferent and afferent activity. In addition, mRNA levels of CCL2 and CCR2 in L6-S1 dorsal root ganglia (DRG) were measured to assess afferent sensitization. Immunofluorescent staining of CX3CR1, GFAP, and CCR2 in the L6 spinal cord was also conducted to investigate glial activation and central sensitization. RESULTS: OAB mice showed bladder overactivity evidenced by decreased intercontraction interval (3.56 ± 0.51 vs. 5.76 ± 0.95 min in sham mice), increased non-voiding contractions (0.39 ± 0.11 vs. 0.13 ± 0.07/min in sham mice), and inefficient voiding (72.1 ± 8.6% vs. 87.1 ± 9.5% in sham mice). Increased M2, M3, ß2, ß3, P2X2 , P2X3 , P2X4 , and P2X7 levels in the bladder and increased CCL2 and CCR2 in DRG indicate bladder efferent and afferent hyperexcitability. In addition, CX3CR1, GFAP, and CCR2 in the L6 spinal cord were upregulated in OAB mice. However, the CON group exhibited reduced ß2, ß3, P2X2 , P2X3 , P2X4 , and P2X7 levels in the bladder, reduced CCL2 and CCR2 in DRG, which are markers of afferent hyperexcitability, and reduced immunoreactivities of CX3CR1, GFAP, and CCR2 in the L6 spinal cord, which are markers of the central sensitization. Moreover, the CON group showed better improvements in nonvoiding contractions (0.16 ± 0.09 vs. 0.44 ± 0.17/min) and voiding efficiency (93.9 ± 7.4% vs. 76.5 ± 13.1%) and reductions in bladder ß3 receptors and CCL2 of L6-S1 DRG, and immunoreactivities of CX3CR1 and GFAP in the L6 spinal cord compared to the CES group. CONCLUSIONS: Continuous mirabegron treatment seems to prevent central sensitization and, thus, might be desirable for long-term disease control of OAB.

Antifibrosis treatment by inhibition of VEGF, FGF, and PDGF receptors improves bladder wall remodeling and detrusor overactivity in association with modulation of C-fiber afferent activity in mice with spinal cord injury.

AIMS: Spinal cord injury (SCI) above the sacral level causes bladder dysfunction and remodeling with fibrosis. This study examined the antifibrotic effects using nintedanib, an inhibitor of vascular endothelial growth factor, fibroblast growth factor, and platelet-derived growth factor receptors, on detrusor overactivity (DO) and bladder fibrosis, as well as the modulation mechanisms of C-fiber afferent pathways. METHODS: Thirty female C57BL/6 mice were divided into group A (spinal intact), group B (SCI with vehicle), and group C (SCI with nintedanib). At 2 weeks after SCI, vehicle or 50 mg/kg nintedanib was administered subcutaneously for 2 weeks. Then, cystometry was conducted, followed by RT-PCR measurements of fibrosis-related molecules, muscarinic, ß-adrenergic, TRP and purinergic receptors in the bladder or L6-S1 dorsal root ganglia (DRG). Trichrome stain and Western blot analysis of transforming growth factor-beta and fibronectin were performed in the bladder. TRPV1 expression in L6 DRG was measured by immunohistochemistry. RESULTS: In cystometry, intercontraction intervals, nonvoiding contractions, voided volume, and voiding efficiency were significantly improved in group C versus group B. RT-PCR, Western blotting, and trichrome staining revealed the fibrotic changes in the bladder of group B, which was improved in group C. Increased messenger RNA levels of TRPV1, TRPA1, P2X2 , and P2X3 in DRG of group B were significantly decreased in group C. TRPV1 immunoreactivity in DRG was increased in group B, but decreased in group C. CONCLUSIONS: Nintedanib improves storage and voiding dysfunctions and bladder fibrosis in SCI mice. Also, nintedanib-induced improvement of DO is associated with reduced expression of C-fiber afferent markers, suggesting the modulation of bladder C-fiber afferent activity.

Frequency and clinical significance of short cervix in patients with preterm premature rupture of membranes.

OBJECTIVE: Cervical length measurement has been uggested as a useful tool for predicting intra-amniotic infection/inflammation in preterm labor, but little information is available in the setting of preterm premature rupture of membranes (pPROM). We aimed to determine whether a short cervical length is independently associated with an increased risk of intra-amniotic infection or inflammation and impending preterm delivery in women with pPROM. METHODS: This was a retrospective cohort study involving 171 consecutive singleton pregnant women with pPROM (21+0-33+6 weeks' gestation), who underwent amniocentesis. Amniotic fluid (AF) was cultured, and assayed for interleukin (IL)-6 and IL-8. Cervical length was measured at the time of amniocentesis by transvaginal ultrasonography with an aseptic technique. Short cervical length was defined as a cervical length of ≤15 mm. Intra-amniotic infection was defined as a positive AF culture for microorganisms and intra-amniotic inflammation was defined as elevated AF concentrations of IL-6 or IL-8 (IL-6 ≥1.5 ng/mL and/or IL-8 ≥1.3 ng/mL). RESULTS: Fifty (29.2%) women had a sonographic cervical length of ≤15mm. On univariate analysis, short cervical length was associated with an increased risk for intra-amniotic infection and/or inflammation; no other parameters studied showed a significant association. Multivariable analyses indicated that short cervical length was significantly associated with a higher risk of impending preterm delivery (within 2 days of measurement, within 7 days of measurement, and before 34 weeks), and remained significant after adjustment for potential confounders. CONCLUSION: In women with pPROM, short cervical length is associated with an increased risk for intra-amniotic infection/inflammation and associated with impending preterm delivery, independent of the presence of intra-amniotic infection/inflammation.

A common polymorphism in pre-microRNA-146a is associated with lung cancer risk in a Korean population.

INTRODUCTION: MicroRNAs (miRs) play important roles in the development and progression of human cancers. MiR-146a down-regulates epidermal growth factor receptor and the nuclear factor-κB regulatory kinase interleukin-1 receptor-associated kinase 1 genes that play important roles in lung carcinogenesis. This study was conducted to evaluate the association between rs2910164C>G, a functional polymorphism in the pre-miR-146a, and lung cancer risk. MATERIAL AND METHODS: The rs2910164C>G genotypes were determined in 1094 patients with lung cancer and 1100 healthy controls who were frequency matched for age and gender. RESULTS: The rs2910164 CG or GG genotype was associated with a significantly decreased risk for lung cancer compared to that of the CC genotype (adjusted odds ratio=0.80, 95% confidence interval=0.66-0.96, P=0.02). When subjects were stratified according to smoking exposure (never, light and heavy smokers), the effect of the rs2910164C>G genotype on lung cancer risk was significant only in never smokers (adjusted odds ratio=0.66, 95% confidence interval=0.45-0.96, P=0.03, under a dominant model for the C allele) and decreased as smoking exposure level increased (Ptrend<0.001). In line with this result, the level of miR-146a expression in the tumor tissues was significantly higher in the GG genotype than in the CC or CG genotype only in never-smokers (P=0.02). CONCLUSIONS: These findings suggest that the rs2910164C>G in pre-miR-146a may contribute to genetic susceptibility to lung cancer, and that miR-146a might be involved in lung cancer development.

Association between genetic variants in pre-microRNAs and survival of early-stage NSCLC.

INTRODUCTION: MicroRNAs (miRNAs) are an abundant class of small non-protein-coding RNAs that function as negative gene regulators. Recent evidence indicates that altered miRNA expression plays an important role in the initiation and progression of lung cancer. Single nucleotide polymorphisms (SNPs) in pre-miRNAs could alter miRNAs processing, or expression, and hence, could influence the prognosis of lung cancer. To test this hypothesis, we evaluated the effects of four SNPs in pre-miRNAs (pre-miR-146a rs2910164, pre-miR-149 rs2292832, pre-miR-196a rs11614913, and pre-miR-499 rs3746444) on the survival outcomes of patients with early-stage non-small-cell lung cancer (NSCLC). METHODS: Three hundred sixty-three patients with surgically resected NSCLC were enrolled. The four SNPs were genotyped using a polymerase chain reaction-restriction fragment length polymorphism assay. The genotype associations with overall survival (OS) and disease-free survival (DFS) were analyzed. RESULTS: Of the four SNPs examined, the pre-miR-149 rs2292832T>C and pre-miR-196a rs11614913C>T were found to be significantly associated with OS and DFS. The rs2292832 TC or CC genotype exhibited a significantly better OS and DFS compared with the rs2292832 TT genotype (adjusted hazard ratio [aHR] for OS, 0.66; 95% confidence interval [CI], 0.47-0.92; p = 0.01 and aHR for DFS, 0.64; 95% CI, 0.48-0.87; p = 0.004). For the pre-miR-196a rs11614913C>T, patients with the CT or TT genotype had a significantly better OS and DFS than those with the CC genotype (aHR for OS, 0.70; 95% CI, 0.49-0.99; p = 0.05 and aHR for DFS, 0.66; 95% CI, 0.48-0.90; p = 0.01). When the two SNPs were combined, OS and DFS improved in a dose-dependent manner as the number of good genotypes increased (p = 0.002 and 0.0001, respectively). CONCLUSIONS: These results suggest that miR-149 and miR-196a may be involved in the pathogenesis of NSCLC, and that rs2292832 and rs11614913 can be used as prognostic markers for patients with surgically resected early-stage NSCLC.