Diabetic bladder dysfunction: current translational knowledge

An analysis of urodynamic parameters in diabetic and nondiabetic women

OBJECTIVES

Diabetes is highly prevalent worldwide, with an estimated 536 million living with diabetes in 2021, and that number projected to increase to 783 million by 2045. Diabetic bladder dysfunction is thought to affect up to 60%-90% of individuals with diabetes and can significantly impact quality of life. Despite the prevalence of diabetic bladder dysfunction, the exact pathophysiological mechanism, and resulting clinical presentation, remains debated. Our objective was to compare urodynamic parameters between diabetic and nondiabetic women, assessing the impact of various markers of diabetes severity on bladder function.

METHODS

A retrospective chart review was conducted on female patients aged 18 and above who underwent urodynamic studies at a single tertiary care university hospital system from 2014 to 2020. Patients were categorized based on diabetes status, and diabetes severity including duration of disease, hemoglobin A1c levels, insulin dependence, and markers of end-organ dysfunction. Urodynamic variables, including compliance, bladder voided efficiency, bladder contractility index, postvoid residual, maximum flow rate, capacity, voided volume, and detrusor overactivity, were assessed by two independent reviewers. Statistical analyses were performed to assess the impact of diabetes and diabetic severity on urodynamic parameters.

RESULTS

A total of 652 female patients were included in the study, of which, 152 (23.3%) had diabetes, with an average duration of diagnosis of 82.3 months. Diabetic women were older and had higher body mass index compared to nondiabetic women. Diabetic retinopathy and neuropathy were present in 18% and 54.6% of diabetic patients, respectively. Significant differences in urodynamic parameters were observed between diabetic and nondiabetic women, with diabetic women showing higher rates of detrusor overactivity (p = 0.01), particularly associated with increasing BMI (p = 0.03). However, classic markers of diabetes severity including duration, as well as markers of end-organ damage, showed mixed associations with urodynamic changes.

CONCLUSIONS

Despite the prevalence of diabetic bladder dysfunction and its impact on patient quality of life, the exact mechanisms and clinical presentation remain elusive. Our study highlights the significant differences in urodynamic parameters between diabetic and nondiabetic women, emphasizing the need for further research into the relationship between diabetes and diabetic bladder dysfunction.

Time-dependent progress of lower urinary tract dysfunction in streptozotocin-induced diabetic rats with or without low-dose insulin treatment

Objectives: To examine time-dependent functional and structural changes of the lower urinary tract in streptozotocin-induced diabetic rats with or without low-dose insulin treatment and explore the pathophysiological characteristics of insulin therapy on lower urinary tract dysfunction (LUTD) caused by diabetes mellitus (DM). Methods: Female Sprague-Dawley rats were divided into five groups: normal control (NC) group, 4 weeks insulin-treated DM (4-DI) group, 4 weeks DM (4-DM) group, 8 weeks insulin-treated DM (8-DI) group and 8 weeks DM (8-DM) group. DM was initially induced by i.p. injection of streptozotocin (65 mg/kg), and then the DI groups received subcutaneous implantation of insulin pellets under the mid dorsal skin. Voiding behavior was evaluated in metabolic cages. The function of bladder and urethra in vivo were evaluated by simultaneous recordings of the cystometrogram and urethral perfusion pressure (UPP) under urethane anesthesia. The function of bladder and urethra in vitro were tested by organ bath techniques. The morphologic changes of the bladder and urethra were investigated using Hematoxylin-Eosin and Masson's staining. Results: Both 4-and 8-weeks diabetic rats have altered micturition patterns, including increased 12-h urine volume, urinary frequency/12 hours and voided volume. In-vivo urodynamics showed the EUS bursting activity duration is longer in 4-DM group and shorter in 8-DM group compared to NC group. UPP change in 8-DM were significantly lower than NC group. While none of these changes were found between DI and NC groups. Organ bath showed the response to Carbachol and EFS in bladder smooth muscle per tissue weights was decreased significantly in 4- and 8-weeks DM groups compared with insulin-treated DM or NC groups. In contrast, the contraction of urethral muscle and maximum urethral muscle contraction per gram of the tissue to EFS stimulation were significantly increased in 4- and 8-weeks DM groups. The thickness of bladder smooth muscle was time-dependently increased, but the thickness of the urethral muscle had no difference. Conclusions: DM-induced LUTD is characterized by time-dependent functional and structural remodeling in the bladder and urethra, which shows the hypertrophy of the bladder smooth muscle, reduced urethral smooth muscle relaxation and EUS dysfunction. Low-dose insulin can protect against diuresis-induced bladder over-distention, preserve urethral relaxation and protect EUS bursting activity, which would be helpful to study the slow-onset, time-dependent progress of DM-induced LUTD.

Methylglyoxal and Advanced Glycation End Products (AGEs): Targets for the Prevention and Treatment of Diabetes-Associated Bladder Dysfunction?

Methylglyoxal (MGO) is a highly reactive α-dicarbonyl compound formed endogenously from 3-carbon glycolytic intermediates. Methylglyoxal accumulated in plasma and urine of hyperglycemic and diabetic individuals acts as a potent peptide glycation molecule, giving rise to advanced glycation end products (AGEs) like arginine-derived hydroimidazolone (MG-H1) and carboxyethyl-lysine (CEL). Methylglyoxal-derived AGEs exert their effects mostly via activation of RAGE, a cell surface receptor that initiates multiple intracellular signaling pathways, favoring a pro-oxidant environment through NADPH oxidase activation and generation of high levels of reactive oxygen species (ROS). Diabetic bladder dysfunction is a bothersome urological complication in patients with poorly controlled diabetes mellitus and may comprise overactive bladder, urge incontinence, poor emptying, dribbling, incomplete emptying of the bladder, and urinary retention. Preclinical models of type 1 and type 2 diabetes have further confirmed the relationship between diabetes and voiding dysfunction. Interestingly, healthy mice supplemented with MGO for prolonged periods exhibit in vivo and in vitro bladder dysfunction, which is accompanied by increased AGE formation and RAGE expression, as well as by ROS overproduction in bladder tissues. Drugs reported to scavenge MGO and to inactivate AGEs like metformin, polyphenols, and alagebrium (ALT-711) have shown favorable outcomes on bladder dysfunction in diabetic obese leptin-deficient and MGO-exposed mice. Therefore, MGO, AGEs, and RAGE levels may be critically involved in the pathogenesis of bladder dysfunction in diabetic individuals. However, there are no clinical trials designed to test drugs that selectively inhibit the MGO-AGEs-RAGE signaling, aiming to reduce the manifestations of diabetes-associated bladder dysfunction. This review summarizes the current literature on the role of MGO-AGEs-RAGE-ROS axis in diabetes-associated bladder dysfunction. Drugs that directly inactivate MGO and ameliorate bladder dysfunction are also reviewed here.

Predictive patterns of lower urinary tract symptoms and bacteriuria in adults with type 2 diabetes

Background

Numerous studies demonstrated the risk factors for urological complications in patients with diabetes before sodium-glucose co-transporter 2 inhibitor (SGLT2i) became commercially available. This study aimed to comprehensively investigate urological characteristics in patients with type 2 diabetes (T2DM) after SGLT2i became commercially available.

Methods

We examined 63 outpatients with T2DM suspected of bacteriuria based on urinary sediment examinations. Urine cultures were performed, and lower urinary tract symptoms (LUTS) were assessed via questionnaires. Patients with bacteriuria were assessed using ultrasonography to measure post-void residual volume (PVR). Utilizing demographic and laboratory data, a random forest algorithm predicted LUTS, bacteriuria, and symptomatic bacteriuria (SB).

Results

Thirty-two patients had LUTS and 31 had bacteriuria. High-density lipoprotein cholesterol level was crucial in predicting LUTS, while age was crucial in predicting bacteriuria. In predicting SB among patients with bacteriuria, creatinine level and estimated glomerular filtration rate were crucial. Our models had high predictive accuracy for LUTS (area under the curve [AUC] = 0.846), followed by bacteriuria (AUC = 0.770) and SB (AUC = 0.938) in receiver operating characteristic curve analysis. These predictors were previously reported as risk factors for urological complications. Although SGLT2i use was not an important predictor in our study, all SGLT2i users with bacteriuria had SB and exhibited higher PVR compared to non-SGLT2i users with bacteriuria.

Conclusion

This study's random forest model highlighted distinct essential predictors for each urological condition. The predictors were consistent before and after SGLT2i became commercially available.

Supplementary Information

The online version contains supplementary material available at 10.1007/s13340-023-00687-1.

Predictive value of clinical risk factors for bladder dysfunction in Syrian patients with type 2 diabetes mellitus

Diabetes mellitus (DM) is a prevalent disorder that affects the endocrine and metabolic systems. Among the various complications associated with DM, diabetic bladder dysfunction (DBD) is the most frequently occurring genitourinary complication. The presence of DBD can lead to complications that affect the upper urinary tract, significantly impacting the quality of life for individuals with DM. Therefore, it is crucial to identify early risk factors for DBD and predict its onset. Given the absence of studies involving bladder dysfunction in patients with type 2 diabetes mellitus (T2DM) in Syria, this study aims to examine the risk factors associated with bladder dysfunction in T2DM patients and develop a predictive model to identify DBD early. Patients diagnosed with T2DM were enrolled in six endocrinology centers spread across four Syrian provinces between January 2018 and December 2023. Factors that showed an association with DBD in the bivariate analysis, with a significance level of p < 0.05, were included in a multiple logistic regression analysis. The logistic regression analysis was used to identify independent risk factors and develop a prediction model. The receiver operating characteristic (ROC) curve was used to assess the predictive performance of the identified risk factors and the prediction model for DBD. One hundred and eighty-four patients were included in this study, and they were divided into the DBD group (n = 88) and the non-DBD group (n = 96). Seven variables showed significance in the bivariate analysis. Furthermore, the multiple logistic regression analysis revealed that age (OR [95% CI]: 0.981 [0.614 - 1.337]), p < 0.007; diabetic peripheral neuropathy (DPN) (OR [95% CI]: 1.421 [1.027 - 3.308]), p = 0.03; glycated hemoglobin (HbA1c) (OR [95% CI]: 0.942 [0.821 - 1.141]), p = 0.042; and percentage of monocyte (Mono%) (OR [95% CI]: 1.109 [0.812 - 1.258]), p = 0.031 were independent risk factors for DBD. Analysis of the ROC curve revealed that the area under the curve (AUC) for age, DPN, HbA1c, and Mono were 0.703, 0.541, 0.613, and 0.836, respectively. Age, DPN, HbA1c, and Mono% were risk factors for DBD. The prediction model constructed based on the four risk factors had a good predictive value for predicting the occurrence of DBD.

How do we make progress in phenotyping patients with LUT such as OAB and underactive detrusor, including using urine markers and microbiome data, in order to personalize therapy? ICI-RS 2023: Part 1

INTRODUCTION

Overactive bladder (OAB) and Underactive bladder (UAB) could be associated with metabolic syndrome, affective disorders, sex hormone deficiency, changes in urinary microbiota, functional gastrointestinal disorders, or autonomic nervous system dysfunction.

OBJECTIVES

The aim of this Think Tank was to provide a guide on how to investigate OAB and/or detrusor underactivity (DU) patients to better clarify the underlying pathophysiology and possibly personalize the treatment.

METHODS

A compendium of discussion based on the current evidence related to phenotyping patients with OAB or DU investigating metabolic, neurogical, psychological and gastrointestinal aspects with the aim to personalize the treatment.

RESULTS AND CONCLUSIONS

The article emphasizes the critical significance of adopting a comprehensive yet tailored approach to phenotyping patients with lower urinary tract symptoms, such as OAB and UAB. The intricate interplay between the lower urinary tract and various factors, metabolic, neurological, psychological, and gastrointestinal can define unique LUT profiles, enabling personalized therapies to replace the one-size-fits-all approach.

Predictive value of risk factors for bladder dysfunction in Chinese patients with type 2 diabetes mellitus: A case-control study

OBJECTIVE

To analyze risk factors associated with bladder dysfunction in patients with type 2 diabetes mellitus (T2DM) and to construct a prediction model for early prediction of diabetic bladder dysfunction (DBD).

METHODS

We included hospitalized patients with T2DM from the endocrinology department of Shenzhen Hospital, Southern Medical University, Shenzhen, China, from January 2019 to 2022. Factors associated with DBD in bivariate analysis with a p < 0.05 were included in a multivariate logistic regression analysis. Multivariate logistic regression analysis was used to determine independent risk factors and to construct a prediction model. The prediction model was presented as the model formula. The receiver operating characteristic (ROC) curve was used to evaluate the predictive value of the above risk factors and the prediction model for DBD. The model was internally verified by Boostrap resampling 1000 times.

RESULTS

Two hundred and eleven patients were included in this study, and they were divided into the DBD group (n = 101) and the non-DBD group (n = 110). Eight variables showed significant significance in the bivariate analysis, including age, diabetic peripheral neuropathy (DPN), glycated hemoglobin (HbA1c), urinary microalbumin (mALB), red blood cell count (RBC), white blood cell count (WBC), absolute neutrophil count (ANC), percentage of monocyte (Mono%). Furthermore, multivariate logistic regression analysis revealed that age (OR [95% CI]: 1.077 [1.042-1.112]), p < 0.001; DPN (OR [95% CI]: 2.373 [1.013-5.561]), p = 0.047; HbA1c (OR [95% CI]: 1.170 [1.029-1.330]), p = 0.017 and ANC (OR [95% CI]: 1.234 [1.059-1.438]), p = 0.007 were independent risk factors for the DBD. The prediction model formula was Logit (p) = -6.611 + 0.074 age + 0.864 DPN + 0.157 HbA 1 c + 0.078 ANC. The area under the ROC curve (AUC) for the four risk factors were 0.676, 0.582, 0.618, and 0.674, respectively. The prediction model predicted DBD with higher accuracy than the individual risk factors, AUC = 0.817 (95% CI: 0.757-0.877), and the sensitivity and specificity were 88.1% and 50.0%, respectively. The model internal validation results showed that the AUC = 0.804 (95% CI: 0.707-0.901), and the calibration curve is close to the ideal diagonal line.

CONCLUSIONS

Age, DPN, HbA1c, and ANC were risk factors for DBD. The prediction model constructed based on the four risk factors had a good predictive value for predicting the occurrence of DBD.

Differentially Expressed mRNA in Streptozotocin-Induced Diabetic Bladder Using RNA Sequencing Analysis

PURPOSE

To detect elements governing the pathogenesis of diabetic cystopathy (DC), mRNA sequencing was carried out for bladder tissues from normal rats and those with induced diabetes mellitus (DM). This research therefore offers possible underlying molecular pathways for the advancement of DC in relation to differential mRNA expression, together with visceral functional and architectural alterations noted in individuals with this condition.

METHODS

An intraperitoneal injection of streptozotocin (STZ) was utilized to provoke DM in male Sprague-Dawley rats. Dysregulation and significant variations between normal rats and those with induced DM were then identified by a fold change of ≥ 1.5 with a false discovery rate P < 0.05. Hierarchical clustering/heat map and Gene Ontology/DAVID reference sources were generated. Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis and protein-protein interaction analysis were then performed.

RESULTS

The diabetic rodent group exhibited a greater residual urine volume (4.0 ± 0.4 mL) than their control counterparts (0.7 ± 0.2 mL, P < 0.01) at 12 weeks after diagnosis of diabetes. Expression analysis revealed 16 upregulated and 4 downregulated genes in STZDM bladder samples. A notable increase in expression was seen in PTHLH, TNFAIP6, PRC1, MAPK10, LOC686120, CASQ2, ACTG2, PDLIM3, FCHSD1, DBN1, NKD2, PDLIM7, ATF4, RBPMS2, ITGB1 and HSPB8. A notable decrease in expression was seen in SREBLF1, PBGFR1, PBLD1 and CELF1. Major genetic themes associated with mRNA upregulation and downregulation ware identified via Gene Ontology analysis and KEGG pathways. Protein to protein interaction analysis detected PDLIM3, PDLIM7, ITGB1, ACTG2 as core high frequency nodes within the network.

CONCLUSION

Changes in mRNA expression together with biological process and pathways that contribute to the etiologies underlying visceral impairment of the bladder in DM are evident. Our strategy is promising for recognizing mRNAs exclusive to the bladder in DM that might offer useful targets for diagnosis and treatment.

A Spectrum of Age- and Gender-Dependent Lower Urinary Tract Phenotypes in Three Mouse Models of Type 2 Diabetes

Lower urinary tract symptoms are extremely common in people with diabetes and obesity, but the causes are unclear. Furthermore, it has proven difficult to reliably demonstrate bladder dysfunction in diabetic mouse models, thus limiting the ability to gain mechanistic insights. Therefore, the main objective of this experimental study was to characterize diabetic bladder dysfunction in three promising polygenic mouse models of type 2 diabetes. We performed periodic assessments of glucose tolerance and micturition (void spot assay) for eight to twelve months. Males and females and high-fat diets were tested. NONcNZO10/LtJ mice did not develop bladder dysfunction over twelve months. TALLYHO/JngJ males were severely hyperglycemic from two months of age (fasted blood glucose ~550 mg/dL), while females were moderately so. Although males exhibited polyuria, neither they nor the females exhibited bladder dysfunction over nine months. KK.Cg-A^y/J males and females were extremely glucose intolerant. Males exhibited polyuria, a significant increase in voiding frequency at four months (compensation), followed by a rapid drop in voiding frequency by six months (decompensation) which was accompanied by a dramatic increase in urine leakage, indicating loss of outlet control. At eight months, male bladders were dilated. Females also developed polyuria but compensated with larger voids. We conclude KK.Cg-A^y/J male mice recapitulate key symptoms noted in patients and are the best model of the three to study diabetic bladder dysfunction.

Effects of electroacupuncture on bladder dysfunction and the expression of PACAP38 in a diabetic rat model

Objective: To explore the effects and the possible mechanism of electroacupuncture (EA) on diabetic bladder dysfunction (DBD) in streptozotocin-high fat diet (STZ-HFD) induced type 2 diabetes mellitus (T2DM) rats. Methods: The experiment was divided into Control, diabetic bladder dysfunction, electroacupuncture, and Sham electroacupuncture group. After 8 weeks of electroacupuncture intervention, the body mass, 24 h urine volume, intraperitoneal glucose tolerance test (IPGTT), and urodynamics were detected. After the wet weight of the bladder was detected, the hematoxylin-eosin (HE), Masson's trichrome, and TUNEL were used to analyze histological changes. The PACAP38 expressions in the bladder were detected by Real-time PCR and Western blot. Results: Compared to the Control group, the bladder wet weight, 24 h urine volume, blood glucose, maximum bladder capacity, bladder compliance, bladder wall thickness, the smooth muscle/collagen ratio, and apoptosis rate of the diabetic bladder dysfunction group were significantly increased. Moreover, the body mass and leak point pressure were significantly reduced. Compared with the Sham electroacupuncture group, the bladder wet weight, maximum bladder capacity, bladder compliance, bladder wall thickness, and apoptosis rate of the electroacupuncture group were significantly reduced. In contrast, the leak point pressure was increased. The PACAP38 mRNA and PACAP38 protein expression of the diabetic bladder dysfunction group were significantly lower than the Control group, while electroacupuncture treatment could upregulate PACAP38 mRNA levels and PACAP38 protein expression of diabetic bladder dysfunction model rats. Conclusion: electroacupuncture could ameliorate bladder dysfunction in the diabetic bladder dysfunction model rats by reversing bladder remodeling, which might be mainly mediated by regulating the PACAP38 level.

Diabetes causes NLRP3-dependent barrier dysfunction in mice with detrusor overactivity but not underactivity

Approximately half of the patients with diabetes develop diabetic bladder dysfunction (DBD). The initiation and progression of DBD is largely attributed to inflammation due to dysregulated glucose and the production of toxic metabolites that activate the NOD-, LRR-, and pyrin domain-containing protein 3 (NLRP3) inflammasome. NLRP3 activation leads to the production and release of proinflammatory cytokines and causes urothelial pyroptosis, a form of programmed cell necrosis, which we hypothesize compromises urothelial barrier integrity. Here, we investigated how NLRP3-dependent inflammation impacts barrier function during the progression of diabetes using a type 1 diabetic female Akita mouse model that progresses from an early overactive to a late underactive detrusor phenotype at 15 and 30 wk, respectively. To determine the specific role of NLRP3, Akita mice were crossbred with mice lacking the NLRP3 gene. To determine barrier function, permeability to small molecules was assessed, ex vivo using Evans blue dye and in vivo using sulfo-NHS-biotin. Both ex vivo and in vivo permeabilities were increased in diabetic mice at 15 wk. Expression of uroplakin and tight junction components was also significantly downregulated at 15 wk. Interestingly, diabetic mice lacking the NLRP3 gene showed no evidence of barrier damage or downregulation of barrier genes and proteins. At the 30-wk time point, ex vivo and in vivo barrier damage as well as barrier component downregulation was no longer evident in diabetic mice, suggesting urothelial repair or remodeling occurs between the overactive and underactive stages of DBD. Collectively, these findings demonstrate the role of NLRP3-mediated inflammation in urothelial barrier damage associated with detrusor overactivity but not underactivity.NEW & NOTEWORTHY This is the first study to demonstrate that NLRP3-mediated inflammation is responsible for urothelial barrier damage in type 1 diabetic female Akita mice with an overactive bladder. Eliminating the NLRP3 gene in these diabetic mice prevented barrier damage as a result of diabetes. By the time female Akita mice develop an underactive phenotype, the urothelial barrier has been restored, suggesting that inflammation is a critical causative factor early in the development of diabetic bladder dysfunction.

Inflammation triggered by the NLRP3 inflammasome is a critical driver of diabetic bladder dysfunction

Diabetes is a rapidly expanding epidemic projected to affect as many as 1 in 3 Americans by 2050. This disease is characterized by devastating complications brought about high glucose and metabolic derangement. The most common of these complications is diabetic bladder dysfunction (DBD) and estimates suggest that 50-80% of patients experience this disorder. Unfortunately, the Epidemiology of Diabetes Interventions and Complications Study suggests that strict glucose control does not decrease ones risk for incontinence, although it does decrease the risk of other complications such as retinopathy, nephropathy and neuropathy. Thus, there is a significant unmet need to better understand DBD in order to develop targeted therapies to alleviate patient suffering. Recently, the research community has come to understand that diabetes produces a systemic state of low-level inflammation known as meta-inflammation and attention has focused on a role for the sterile inflammation-inducing structure known as the NLRP3 inflammasome. In this review, we will examine the evidence that NLRP3 plays a central role in inducing DBD and driving its progression towards an underactive phenotype.

Smooth Muscle Insulin Receptor Deletion Causes Voiding Dysfunction: A Mechanism for Diabetic Bladder Dysfunction

Diabetic bladder dysfunction (DBD) is the most common complication in diabetes. Myogenic abnormalities are common in DBD; however, the underlying mechanisms leading to these remain unclear. To understand the importance of smooth muscle insulin receptor (IR)-mediated signaling in the pathogenesis of DBD, we conditionally deleted it to achieve either heterozygous (SMIR+/-) or homozygous (SMIR-/-) deletion in smooth muscle cells. Despite impaired glucose and insulin tolerance seen with SMIR-/- mice, both SMIR+/- and SMIR-/- mice exhibited normal blood glucose and plasma insulin levels. Interestingly, these mice had abnormal voiding phenotypes, that included urinary frequency and small voids, and bladder smooth muscle (BSM) had significantly diminished contraction force. Morphology revealed a dilated bladder with thinner BSM layer, and BSM bundles were disorganized with penetrating interstitial tissue. Deletion of IR elevated FoxO and decreased mTOR protein expression, which further decreased the expression of Chrm3, P2x1, Sm22, and Cav1.2, crucial functional proteins for BSM contraction. Furthermore, we determined the expression of adiponectin in BSM, and deletion of IR in BSM inhibited adiponectin-mediated signaling. In summary, disruption of IR-mediated signaling in BSM caused abnormalities in proliferation and differentiation, leading to diminished BSM contractility and a voiding dysfunction phenotype that recapitulates human DBD.

Functional and Immunofluorescence Evaluations of Vascular and Neural Integrities in Urinary Bladder of Streptozotocin-Induced Diabetic Mice

Purpose

To assess functional and structural changes in vascular and neural structures associated with diabetic bladder dysfunction (DBD) in the bladders of streptozotocin (STZ)-induced diabetic mice.

Methods

Eight-week-old C57BL/6 mice were injected with STZ at 50 mg/kg daily for 5 consecutive days. Catheters were inserted 12 weeks later, and 5 days after catheter placement bladder functions were assessed by conscious cystometry. Neurovascular and extracellular matrix marker changes in harvested urinary bladders were investigated by immunofluorescent staining. Body weights and fasting and postprandial blood glucose levels were measured 12 weeks after STZ injection.

Results

STZ-induced diabetic mice had significantly lower body weights and significantly higher blood glucose levels. Assessment of bladder function in STZ-induced diabetic mice revealed a nearly 3-fold increase in bladder capacity and intercontractile interval compared to controls. However, basal pressure, maximal bladder pressure, and threshold pressure were not significantly different. Morphological and structural analysis showed that STZ-induced diabetic mice had significantly reduced microvascular density in lamina propria (33% of the nondiabetic control values), and severely decreased nerve contents in the detrusor region (42% of the nondiabetic control values).

Conclusions

STZ-induced diabetic mice exhibit functional and structural derangements in urinary bladder. The present study provides a foundation and describes a useful means of evaluating the efficacies of therapeutic targets and exploring the detailed mechanism of DBD.

Suo Quan Wan ameliorates bladder overactivity and regulates neurotransmission via regulating Myosin Va protein expression

BACKGROUND

Ancient prescriptions of Suo Quan Wan (SQW) have therapeutic effects on diabetic bladder dysfunction. However, the underlying mechanism remains unclear. Here, we hypothesized that SQW ameliorates bladder overactivity and regulates neurotransmission via regulating Myosin Va protein expression.

METHODS

After diabetic rats were induced by streptozotocin (65 mg/kg), the model of diabetic bladder dysfunction was established by detecting fasting blood glucose, urodynamic test, in vitro muscle strip experiments, and histological examination. One week after induction, SQW was given to observe the therapeutic effect. The expression levels of Myosin Va in control, Model, SQW L and SQW H groups were detected by RT-qPCR, RNAscope and immunofluorescence assay. The expression levels of ChAT, SP, nNOS and VIP proteins were observed by immunofluorescence assay. After knockdown and overexpression of Myosin Va, the expression changes of ChAT, SP, nNOS and VIP and the regulatory role of SQW were observed.

RESULTS

STZ-induced DM rats had significantly higher serum glucose levels and lower body weight. Compared with the diabetic rats, SQW treatment significantly improved urination function with decreased residual volume (RV), bladder compliance (BC), non-voiding contractions (NVCs), and increased voided efficiency (VE). In addition, contractile responses of muscle strips to electrical-field stimulation (EFS), carbachol (CCh), KCl were significantly lower in the SQW H and SQW L groups than those in the model group. RT-qPCR found that the expression of Myosin Va in the bladder tissue or bladder neurons in model group was significantly increased compared with the control group, and SQW treatment significantly decreased the levels of Myosin Va. In DM rats, ChAT and SP expression were significantly increased, while nNOS and VIP expression were significantly decreased, and SQW improved this phenomenon. Interestingly, SQW ameliorated the abnormal expression of ChAT, SP, nNOS and VIP caused by myosin Va knockdown, and Myosin Va overexpression results are consistent with these.

CONCLUSIONS

SQW ameliorates overactive bladder and regulate neurotransmission via regulating Myosin Va mRNA and protein expression.

Potential role of oxidative stress in the pathogenesis of diabetic bladder dysfunction

Diabetes mellitus is a chronic metabolic disease, posing a considerable threat to global public health. Treating systemic comorbidities has been one of the greatest clinical challenges in the management of diabetes. Diabetic bladder dysfunction, characterized by detrusor overactivity during the early stage of the disease and detrusor underactivity during the late stage, is a common urological complication of diabetes. Oxidative stress is thought to trigger hyperglycaemia-dependent tissue damage in multiple organs; thus, a growing body of literature has suggested a possible link between functional changes in urothelium, muscle and the corresponding innervations. Improved understanding of the mechanisms of oxidative stress could lead to the development of novel therapeutics to restore the redox equilibrium and scavenge excessive free radicals to normalize bladder function in patients with diabetes.

Anti-inflammation properties of resveratrol in the detrusor smooth muscle of the diabetic rat

PURPOSE

In this paper, we aimed to prove that resveratrol can inhibit inflammation in the detrusor smooth muscle of diabetic rats, which may provide a new direction for diabetic cystopathy (DCP) treatment.

METHODS

We induced a Sprague-Dawley (SD) rat model of type 1 diabetes by intraperitoneal injections of streptozotocin (STZ). Then, we separated the SD rats into four groups: (1) an excipient-treated control group; (2) a resveratrol-treated control group; (3) an excipient-treated streptozotocin (STZ)-injected group; and (4) a resveratrol-treated STZ-injected group. We administered the resveratrol or excipient by intragastric administration. After 12 weeks of diabetes induction, we measured the blood-sugar concentrations and bladder weights, and we took the bladder tissues of each group of rats for hematoxylin-eosin staining to observe the histological changes. We used real-time quantitative polymerase chain reaction (qPCR) and Western blotting to analyze the expression levels of tumor necrosis factor-alpha (TNF-α), nuclear factor kappa B (NF-κB), interleukin (IL)-6, and IL-1β.

RESULTS

The bodyweights of the diabetic rats were appreciably reduced, while the bladder weights and blood-glucose concentrations were substantially increased. Oral resveratrol could not improve the changes in the bodyweights and blood-glucose concentrations, but it had a certain effect on the bladder weights. In a macroscopic evaluation, the bladder walls of the STZ-induced diabetes rats were thickened, and, from the H&E staining, we could see that the bladder tissues of the diabetic rats had inflammatory cell infiltration, edema, and the capillary congestion of the mucosa and lamina propria. After resveratrol treatment, the bladder-wall thickening was reduced, and the tissue damage and inflammation were significantly ameliorated. We could associate all these changes with markedly heightened expressions of TNF-α, IL-1β, IL-6, and NF-κB in the detrusor smooth muscle (DSM) tissues of the diabetic rats. Oral treatment with resveratrol alleviated the expressivity of the inflammatory cytokines in the DSM tissues.

CONCLUSIONS

Resveratrol treatment ameliorated the histological changes in the bladder and inhibited the expressions of DSM-tissue inflammatory factors in diabetes rats. Resveratrol may provide a new direction of research for the treatment of diabetic cystopathy.

Established and emerging treatments for diabetes-associated lower urinary tract dysfunction

Dysfunction of the lower urinary tract (LUT) including urinary bladder and urethra (and prostate in men) is one of the most frequent complications of diabetes and can manifest as overactive bladder, underactive bladder, urinary incontinence, and as aggravated symptoms of benign prostate hyperplasia. We have performed a selective literature search to review existing evidence on efficacy of classic medications for the treatment of LUT dysfunction in diabetic patients and animals, i.e., α1-adrenoceptor and muscarinic receptor antagonists, β3-adrenoceptor agonists, and phosphodiesterase type 5 inhibitors. Generally, these agents appear to have comparable efficacy in patients and/or animals with and without diabetes. We also review effects of antidiabetic medications on LUT function. Such studies have largely been performed in animal models. In the streptozotocin-induced models of type 1 diabetes, insulin can prevent and reverse alterations of morphology, function, and gene expression patterns in bladder and prostate. Typical medications for the treatment of type 2 diabetes have been studied less often, and the reported findings are not yet sufficient to derive robust conclusions. Thereafter, we review animal studies with emerging medications perhaps targeting diabetes-associated LUT dysfunction. Data with myoinositol, daidzein, and with compounds that target oxidative stress, inflammation, Rac1, nerve growth factor, angiotensin II receptor, serotonin receptor, adenosine receptor, and soluble guanylyl cyclase are not conclusive yet, but some hold promise as potential treatments. Finally, we review nonpharmacological interventions in diabetic bladder dysfunction. These approaches are relatively new and give promising results in preclinical studies. In conclusion, the insulin data in rodent models of type 1 diabetes suggest that diabetes-associated LUT function can be mostly or partially reversed. However, we propose that considerable additional experimental and clinical studies are needed to target diabetes itself or pathophysiological changes induced by chronic hyperglycemia for the treatment of diabetic uropathy.

Daidzein attenuates urinary bladder dysfunction in streptozotocin-induced diabetes in rats by NOX-4 and RAC-1 inhibition

Reactive oxygen species via NADPH oxidase (NOX) activation are involved in the pathogenesis of many disease conditions such as diabetes and its complications. In the present study, we have examined the effect of daidzein in the management of diabetic cystopathy. Diabetes was induced in male Sprague Dawley rats via intraperitoneal injection of streptozotocin (STZ) at a dose of 55 mg/kg. After 6 weeks of diabetes induction, animals were treated with daidzein orally at a dose of 25, 50, and 100 mg/kg for 4 weeks. Diabetic animals showed increase (p < 0.001) in bladder capacity (4.32 ± 0.43 mL) and residual volume (2.53 ± 0.19 mL) when compared with normal control animals (2.10 ± 0.40 mL and 0.51 ± 0.12 mL res). Treatment with daidzein at dose of 50 and 100 mg/kg significantly reduced the elevated bladder capacity (2.91 ± 0.11 mL, p < 0.01 and 2.65 ± 1.13 mL, p < 0.001) and residual volume (1.40 ± 0.15 mL, p < 0.001 and 1.15 ± 0.05 mL, p < 0.001). Daidzein-treated animals also showed improvement in voiding efficiency. Elevated threshold and baseline pressure were also found to be reduced in diabetic animals after 4 weeks of daidzein treatment. Daidzein treatment also prevented the loss of antioxidant enzymes in the urinary bladder and also reduced the expression of NOX-4 and RAC-1 in the bladder. From the results, it can be concluded that daidzein showed a beneficial effect on urinary bladder dysfunction in diabetic animals.

Diabetic bladder dysfunction progresses from an overactive to an underactive phenotype in a type-1 diabetic mouse model (Akita female mouse) and is dependent on NLRP3

AIMS

Diabetic bladder dysfunction (DBD) is a prevalent diabetic complication thought to progress from overactive (OAB) to underactive (UAB) bladder. Previously we found OAB at 15 weeks in the Akita mouse, a genetic model of Type 1 diabetes. The first aim of this study assesses bladder function at 30 weeks to assess progression. In addition, inflammation triggered by the NLRP3 inflammasome is implicated in DBD. In a second aim we assessed a role for NLRP3 by crossing Akita mice with NLRP3^-/- mice.

MAIN METHODS

Akita mice were bred with NLRP3^-/- mice. The effect of diabetes was assessed by comparing nondiabetic to diabetic mice (all NLRP3^+/+). The effect of diabetes in the absence of the NLRP3 inflammasome was assessed by comparing nondiabetic/NLRP3^-/- to diabetic/NLRP3^-/- mice. Mice were assessed at 30 weeks for blood glucose (glucometer), inflammation (Evans blue), bladder morphology (histology) and bladder function (urodynamics).

KEY FINDINGS

At 30 weeks blood glucose of nondiabetics and diabetics was not affected by the presence of absence of NLRP3. Diabetic/NLRP3^+/+ mice showed bladder inflammation and detrusor hypertrophy which was blocked in the diabetic/NLRP3^-/- mice, clearly showing a role for NLRP3. When bladder function was examined, diabetic/NLRP3^+/+ showed an increase in voiding volume and a decrease in frequency, two signs of underactive bladder. However, in the NLRP3^-/- mice, diabetes was unable to effectuate these changes, demonstrating that NLRP3-induced inflammation is responsible for UAB symptoms in these mice.

SIGNIFICANCE

Akita diabetic mice progress from OAB to UAB. NLRP3 is a possible target to treat DBD.

Long-Lasting Exendin-4-Loaded PLGA Nanoparticles Ameliorate Cerebral Ischemia/Reperfusion Damage in Diabetic Rats

Exendin-4 (Ex-4) is an incretin mimetic agent approved for diabetes treatment and neuronal protection. However, the required frequent injections restrict its clinical application. We prepared Ex-4-loaded poly(d,l-lactide-co-glycolide) nanoparticles (PEx-4) and investigated their effect on cerebral ischemia/reperfusion (IR) injury associated with micturition center damage-induced cystopathy in diabetic rats. Using ten minutes of bilateral carotid artery occlusion combined with hemorrhage-induced hypotension of the IR model in streptozotocin-induced type 1 diabetic (T1DM) Wistar rats, we compared the effects of Ex-4 and PEx-4 on prefrontal cortex edema, voiding function and oxidative stress including cerebral spinal fluid (CSF) reference H₂O₂ (RH₂O₂) and HOCl (RHOCl) levels, endoplasmic reticulum (ER) stress, apoptosis, autophagy and pyroptosis signaling in brain and bladder by Western blot and immunohistochemistry. Single injection of PEx-4 displayed higher CSF antioxidant activity and a long-lasting hypoglycemic effect compared to Ex-4 in rats. T1DM and IR primarily enhanced CSF RH₂O₂, and pIRE-1/caspase-12/pJNK/CHOP-mediated ER stress, caspase-3/PARP-mediated apoptosis, Beclin-1/LC3B-mediated autophagy and caspase-1/IL-1β-mediated pyroptosis signaling in the damaged brains. Our data further evidenced that PEx-4 were more efficient than Ex-4 in attenuating IR-evoked prefrontal cortex edema, the impairment in micturition center and the enhanced level of CSF RH₂O₂ and HOCl, ER stress, apoptosis, autophagy and pyroptosis parameters in the damaged brains, but had less of an effect on IR-induced voiding dysfunction in bladders of T1DM rats. In summary, PEx-4 with stronger antioxidant activity and long-lasting bioavailability may efficiently confer therapeutic efficacy to ameliorate IR-evoked brain damage through the inhibitory action on oxidative stress, ER stress, apoptosis, autophagy and pyroptosis signaling in diabetic rats.

Diabetic Peripheral Neuropathy and Urological Complications in Type 1 Diabetes: Findings From the Epidemiology of Diabetes Interventions and Complications Study

OBJECTIVE

To evaluate associations between diabetic peripheral neuropathy (DPN) and urological complications in men and women with type 1 diabetes (T1D).

RESEARCH DESIGN AND METHODS

Measurements of DPN at Epidemiology of Diabetes Intervention and Complications (EDIC) years 1, 14, and 17 and urological complications at EDIC year 17 were examined in 635 men (mean age 51.6 years, diabetes duration 29.5 years) and 371 women (mean age 50.6 years, diabetes duration 29.8 years) enrolled in the Diabetes Control and Complications Trial (DCCT)/EDIC study. DPN was defined by symptoms, signs, and abnormal electrophysiology or by abnormal Michigan Neuropathy Screening Instrument (MNSI) examination or questionnaire scores.

RESULTS

Erectile dysfunction (ED) in combination with lower urinary tract symptoms (LUTS) was reported in 15% of men and female sexual dysfunction (FSD), LUTS, and urinary incontinence (UI) in 16% of women. Adjusted for age, drinking status, BMI, depression, DCCT/EDIC time-weighted mean HbA1c, microalbuminuria, hypertension, triglycerides, and statin medication use, the odds of reporting ED and LUTS versus no ED or LUTS at EDIC year 17 were 3.52 (95% CI 1.69, 7.31) times greater in men with confirmed DPN at EDIC year 13/14 compared to men without confirmed DPN. Compared to men without DPN, men with DPN based on abnormal MNSI examination or questionnaire scores had significantly higher odds of reporting ED and LUTS versus no ED or LUTS at EDIC year 17. There were no significant differences in DPN between women reporting both FSD and LUTS/UI compared with those without FSD or LUTS/UI at EDIC year 17.

CONCLUSIONS

In long-standing T1D, DPN is associated with the later development of urological complications in men.

Longitudinal patterns of urinary incontinence and associated predictors in women with type 1 diabetes

AIMS

Urinary incontinence (UI) in women is a dynamic condition with numerous risk factors yet most studies have focused on examining its prevalence at a single time. The objective of this study was to describe the long-term time course of UI in women with type 1 diabetes (T1D).

METHODS

Longitudinal data in women with T1D were collected from 568 women in the Epidemiology of Diabetes Interventions and Complications (EDIC) study, the observational follow-up of the Diabetes Control and Complications Trial (DCCT) cohort. Over a 12-year period, participants annually responded to whether they had experienced UI in the past year.

RESULTS

We identified four categories of UI in this population over time: 205 (36.1%) women never reported UI (no UI), 70 (12.3%) reported it one or two consecutive years only (isolated UI), 247 (43.5%) periodically changed status between UI and no UI (intermittent UI), and 46 (8.1%) reported UI continuously after the first report (persistent UI). Compared to women reporting no/isolated UI, women displaying the intermittent phenotype were significantly more likely to be obese (OR: 1.86, 95% CI 1.15, 3.00) and report prior hysterectomy (OR: 2.57, 95% CI: 1.39, 4.77); whereas women with persistent UI were significantly more likely to have abnormal autonomic function (OR: 2.36, 95% CI: 1.16-4.80).

CONCLUSIONS

UI is a dynamic condition in women with T1D. Varying risk factors observed for the different phenotypes of UI suggest distinctive pathophysiological mechanisms. These findings have the potential to be used to guide individualized interventions for UI in women with diabetes.

Effectiveness and Long-term Outcomes of Nerve-Sparing Radical Hysterectomy for Cervical Cancer

BACKGROUND

Radical hysterectomy (RH) is a type of radical surgery for cervical cancer. Urinary dysfunction due to RH worsens postoperative quality of life of patients with cervical cancer. Nerve-sparing RH (NSRH) technique has been used as an effective means to conserve urinary function. However, few reports have examine long-term outcomes after NSRH. This study describes the details and long-term outcomes of our nerve-sparing technique.

METHODS

Sixty-one patients underwent radical hysterectomy in a 5-year period during which nerve-sparing technique was introduced; of these, 31 patients underwent NSRH and 30 underwent conventional RH. We retrospectively examined their medical records and compared postoperative urinary function and treatment outcomes between these two groups.

RESULTS

The median time required for urinary residual volume to fall to ≤50 mL after removal of the urinary catheter was 6 days (range, 2-20 days) in the NSRH group and 13.5 days (range, 3-46 days) in the RH group. The results were significantly better in the NSRH group (p < 0.05). The mean follow-up period was 2456.3 days (range, 48-4,213 days). Analysis of curability revealed no significant difference between the two groups in local recurrence or long-term survival rates. The 5-year survival rate was 0.861 in the NSRH group and 0.782 in the RH group; the 10-year survival rate was 0.861 in the NSRH group and 0.679 in the RH group.

CONCLUSIONS

NSRH significantly improved postoperative urinary function without worsening local recurrence rates or long-term outcomes.

Metformin abrogates the voiding dysfunction induced by prolonged methylglyoxal intake

Methylglyoxal (MGO) is a reactive carbonyl species found at high levels in blood of diabetic patients. The anti-hyperglycemic drug metformin can scavenger MGO and reduce the formation of advanced glycation end products (AGEs). Here, we aimed to investigate if MGO-induced bladder dysfunction can be reversed by metformin. Male C57/BL6 mice received 0.5% MGO in drinking water for 12 weeks, and metformin (300 mg/kg, daily gavage) was given in the last two weeks. The bladder functions were evaluated by performing voiding behavior assays, cystometry and in vitro bladder contractions. MGO intake markedly elevated the levels of MGO and fluorescent AGEs in serum and reduced the mRNA expression and activity of glyoxalase (Glo1) in bladder tissues. Glucose levels were unaffected among groups. MGO intake also increased the urothelium thickness and collagen content of the bladder. Void spot assays in conscious mice revealed an increased void volume in MGO group. The cystometric assays in anesthetized mice revealed increases of basal pressure, non-voiding contractions frequency, bladder capacity, inter-micturition pressure and residual volume, which were accompanied by reduced voiding efficiency in MGO group. In vitro bladder contractions to carbachol, α,β-methylene ATP and electrical-field stimulation were significantly greater in MGO group. Metformin normalized the changes of MGO and AGEs levels, Glo1 expression and activity, urothelium thickness and collagen content. The MGO-induced voiding dysfunction were all restored by metformin treatment. Our findings strongly suggest that the amelioration of MGO-induced voiding dysfunction by metformin relies on its ability to scavenger MGO, preventing its accumulation in blood.

Experimental long-term diabetes mellitus alters the transcriptome and biomechanical properties of the rat urinary bladder

Diabetes mellitus (DM) is the leading cause of chronic kidney disease and diabetic nephropathy is widely studied. In contrast, the pathobiology of diabetic urinary bladder disease is less understood despite dysfunctional voiding being common in DM. We hypothesised that diabetic cystopathy has a characteristic molecular signature. We therefore studied bladders of hyperglycaemic and polyuric rats with streptozotocin (STZ)-induced DM. Sixteen weeks after induction of DM, as assessed by RNA arrays, wide-ranging changes of gene expression occurred in DM bladders over and above those induced in bladders of non-hyperglycaemic rats with sucrose-induced polyuria. The altered transcripts included those coding for extracellular matrix regulators and neural molecules. Changes in key genes deregulated in DM rat bladders were also detected in db/db mouse bladders. In DM rat bladders there was reduced birefringent collagen between detrusor muscle bundles, and atomic force microscopy showed a significant reduction in tissue stiffness; neither change was found in bladders of sucrose-treated rats. Thus, altered extracellular matrix with reduced tissue rigidity may contribute to voiding dysfunction in people with long-term DM. These results serve as an informative stepping stone towards understanding the complex pathobiology of diabetic cystopathy.

Intravesical Instillation of Norketamine, a Ketamine Metabolite, and Induced Bladder Functional Changes in Rats

This study aimed to determine the mechanism of ketamine-induced cystitis without metabolism. A total of 24 adult male Sprague-Dawley rats were separated into control, ketamine, and norketamine groups. To induce cystitis, rats in the ketamine and norketamine groups were treated with intravesical instillation of ketamine and norketamine by mini-osmotic pump, which was placed in subcutaneous space, daily for 24 h for 4 weeks. After 4 weeks, all rats were subjected to bladder functional tests. The bladders were collected for histological and pathological evaluation. Compared to control, ketamine treatment demonstrated an increase in the bladder weight, high bladder/body coefficient, contractive pressure, voiding volume, collagen deposition, reduced smooth muscle content, damaged glycosaminoglycan layer, and low bladder compliance. Compared to ketamine, norketamine treatment showed more severe collagen deposition, smooth muscle loss, damaged glycosaminoglycan layer, and increased residual urine. Intravesical administration of ketamine and norketamine induced cystitis with different urodynamic characteristics. Norketamine treatment caused more severe bladder dysfunction than ketamine treatment. Direct treatment of the bladder with norketamine induced symptoms more consistent with those of bladder outlet obstruction than ketamine cystitis. Detailed studies of cellular mechanisms are required to determine the pathogenesis of ketamine cystitis.

IR-61 Improves Voiding Function via Mitochondrial Protection in Diabetic Rats

Diabetic bladder dysfunction (DBD) afflicts nearly half of diabetic patients, but effective treatment is lacking. In this study, IR-61, a novel heptamethine cyanine dye with potential antioxidant effects, was investigated to determine whether it can alleviate DBD. Rats were intraperitoneally injected with IR-61 or vehicle after diabetes was induced with streptozotocin. Before evaluating the effects of IR-61 in improving DBD by filling cystometry, we detected its distribution in tissues and subcellular organelles by confocal fluorescence imaging. Near infrared (NIR) imaging showed that IR-61 could accumulate at high levels in the bladders of diabetic rats, and confocal images demonstrated that it was mainly taken up by bladder smooth muscle cells (BSMCs) and localized in mitochondria. Then, filling cystometry illustrated that IR-61 significantly improved the bladder function of diabetic rats. The histomorphometry results showed that IR-61 effectively mitigated the pathological changes in bladder smooth muscle (BSM) in diabetic rats. Furthermore, IR-61 remarkably reduced the number of apoptotic BSMCs and the unfavorable expression of proteins related to the mitochondrial apoptotic pathway (Bcl-2, BAX, Cytochrome C, and cleaved Caspase-9) in diabetic rats. Moreover, the frozen section staining and transmission electron microscopy results proved that IR-61 significantly reduced the reactive oxygen species (ROS) levels and prevented the mitochondrial mass and morphology damage in the BSM of diabetic rats. In addition, IR-61 upregulated the expression of nuclear factor erythroid 2-related factor 2 (Nrf2) and its associated antioxidant proteins in the BSM of diabetic rats. Together, these results indicate that IR-61 can improve the voiding function of rats with DBD by protecting the mitochondria of BSMCs from oxidative stress, which is possibly mediated through the activation of the Nrf2 pathway.

Caffeine improves bladder function in diabetic rats via a neuroprotective effect

Diabetic cystopathy (DCP) is one of the most common complications of diabetes mellitus (DM). A previous study reported that caffeine may improve bladder dysfunction in rats with DM. The aim of the present study was to investigate the mechanisms behind the capacity for caffeine to improve bladder function in rats with DM. Sprague Dawley rats were divided into four groups: control, caffeine, DM and DM plus caffeine treatment (DM + caffeine). Bladder function was measured by urodynamic analyses. The levels of nerve growth factor (NGF), brain-derived neurotrophic factor (BDNF) and calcitonin gene-related peptide (CGRP) in the bladder tissue were detected by ELISA. Apoptosis in the dorsal root ganglion (DRG) was detected by terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling assay. The expression levels of B-cell lymphoma-2 (Bcl-2), Bcl-2-associated X protein (Bax), caspase-3, cleaved caspase-3, caspase-9 and cleaved caspase-9 proteins in the DRG were detected by western blotting. Following treatment with caffeine, the urination time and micturition interval of rats with DM were improved, the bladder wet weight was decreased, and the maximum voiding pressure was increased. Relative to that in the DM group, the expression levels of NGF, BDNF and CGRP in the bladder tissue of DM + caffeine rats increased; cellular apoptosis in the DRG of DM + caffeine rates decreased; and the expression levels of Bcl-2, Bax, cleaved caspase-3 and cleaved caspase-9 proteins in the DRG of DM + caffeine rats were restored to a certain extent. In conclusion, caffeine promotes bladder function in rats with DM through a protective effect on DRG.

The Effect of Low-Intensity Extracorporeal Shockwave Treatment on the Urinary Bladder in an Experimental Diabetic Rat Model

Purpose

Preclinical data increasingly support an impact of low-intensity extracorporeal shockwave therapy (Li-ESWT) on the bladder. We investigated the molecular effects of Li-ESWT on the bladder of a streptozotocin-induced diabetic rat model.

Methods

Fifteen 8-week-old male Wistar rats were randomized into 3 groups: a control group (n=5), a group of diabetic rats without treatment (diabetes mellitus [DM], n=5) and a group of diabetic rats treated with Li-ESWT (DM-ESWT, n=5). A single intraperitoneal dose of streptozotocin (60 mg/kg) was used to induce diabetes. Twenty days after diabetes induction, each rat in the DM-ESWT group received 300 shockwaves with an energy flux density of 0.09 mJ/mm². Sessions were repeated 3 times/week for 2 weeks, followed by a 2-week washout period. Total RNA from bladder tissue was extracted, cDNA was synthesized, and quantitative real-time polymerase chain reaction was performed to analyze the expression pattern of transient receptor potential vanilloid 1 (Trpv1), interleukin-1β (Il1b), and the muscarinic receptors M1, M2, and M3 (Chrm1, Chrm2, and Chrm3).

Results

The expression of Trpv1, Il1b, and Chrm2 genes was significantly different between the 3 groups (P=0.002, P<0.0001, and P=0.011, respectively; 1-way analysis of variance). In the DM group, the expression of all genes was higher than in the control group, but statistical significance was observed only for Trpv1 and Il1b (P=0.002 and P<0.0001, respectively). Li-ESWT significantly reduced the expression of Il1b and Chrm2 (P=0.001 and P=0.011, respectively), whereas a nonsignificant tendency for reduced expression was noted for Trpv1 (P=0.069).

Conclusions

The induction of diabetes was associated with increased expression of genes related to mechanosensation, inflammation/ischemia, and contraction in the rat bladder. Li-ESWT reduced the expression of IL1b, Chrm2, and to a lesser extent Trpv1 toward the control levels, suggesting the therapeutic potential of this treatment modality for diabetic cystopathy.

High percentage of neurologic deficits in the electrophysiology study of the lower urinary tract in patients with detrusor underactivity and chronic urinary retention

OBJECTIVES

Both detrusor underactivity (DU) and bladder outlet obstruction are the common causes of chronic urinary retention. Some novel treatment approaches focus on modulating micturition reflex and external urethral sphincter (EUS) function. This study used electrophysiologic (EP) studies to investigate the micturition reflex and EUS conditions of chronic urinary retention patients.

METHODS

Sixty patients with urodynamic DU and chronic urinary retention were studied using (1) bulbocavernous reflex (BCR) by electric stimulation, (2) electromyography (EMG) of the EUS, and (3) nerve conduction velocity (NCV) studies of the pudendal nerve. The EP findings were analyzed in DU patients with different etiologies.

RESULTS

The BCR was positive in 41.7% of patients. In EMG studies, denervation, reinnervation, and reduced recruitment of the EUS were observed in 21.7%, 71.7%, and 88.3% patients, respectively. Decreased amplitude of pudendal nerve conduction in NCV studies was noted in 73.3% of patients. Patients with sacral neuropathy had a lower BCR positive rate (p = 0.001), a nonsignificant but higher denervation rate (p = 0.059) in EMG studies, and a higher rate of decreased amplitude in NCV (p = 0.011) than those without sacral neuropathy. Excluding patients with sacral neuropathy or diabetes mellitus, a high percentage of neurologic deficits was still detected in EP studies.

CONCLUSIONS

Chronic urinary retention patients with urodynamic DU not only have bladder dysfunction, but also potential neuropathy in the sacral reflexes, pudendal nerve, or urethral sphincter innervation. The neurologic deficits explored in EP studies may affect the decision-making around the therapy to restore the voiding function in DU.

Therapeutic effect of Low intensity Extracorporeal Shock Wave Therapy (Li-ESWT) on diabetic bladder dysfunction in a rat model

Objectives: Low intensity extracorporeal shock wave therapy (Li-ESWT) has proven to be effective and safe for the treatment of various urological disorders including erectile dysfunction and chronic pelvic pain syndrome. In this study, we elucidated the therapeutic effect and possible mechanisms of Li-ESWT on diabetic bladder dysfunction (DBD) in a rat model. Materials and Methods: In all, thirty-two female Sprague-Dawley rats were divided into three groups: normal control (NC), diabetes mellitus (DM) control, and DM Li-ESWT. The two DM groups were given high fat diets for one month, followed by 2 intraperitoneal injections of streptozotocin (STZ) 30 mg/kg separated by one week. Body weight and fasting blood glucose were monitored every week. Only rats with fasting blood glucose 140 mg/dL or more were considered diabetic and used in the subsequent portions of the study. The Li-ESWTs were applied toward the pelvis of the rats twice a week for 4 weeks with energy flux density (EFD) 0.02 mJ/mm², 500 shocks, at 3Hz. All rats underwent plasma insulin tolerance test, conscious cystometry, leak-point pressure (LPP) assessment, and immunohistochemical studies. Results: DM groups had significantly lower insulin sensitivity and higher body weight. Conscious cystometry also revealed voiding dysfunctions. In the DM Li-ESWT group, the rats had significantly improved voiding functions that were reflected in longer micturition intervals and higher LPP compared to DM control. Immunofluorescence in DM control groups showed increased tyrosine hydroxylase (TH) expression and decreased neuronal nitric oxide synthase (nNOS) expression in the longitudinal urethral smooth muscles. Besides, rats had dilations and deformities of suburothelium capillary network of the bladder, revealing the deterioration of the nerve function of the urethra and destruction of the vascularization of the bladder. However, the DM Li-ESWT group exhibited recovery of the nerve expression of the urethra and vascularization of bladder. Conclusions: Li-ESWT ameliorates the bladder dysfunction and urinary continence in the DBD rat model, reflected in restoration of the nerve expression of the urethra and the vascularization of the bladder. Non-invasive Li-ESWT could be an alternative therapeutic option for DBD.

The Complexity of Living with Diabetes and Urinary Incontinence for Older Adults with Multiple Chronic Conditions Receiving Home Care Services: An Interpretive Description Study

Over 40% of older adults with diabetes receiving home-care services experience urinary incontinence. However, experiential knowledge is lacking on how these older adults live with diabetes and incontinence. Interpretive description methodology was used to explore the experiences of 18 older adults with diabetes and urinary incontinence receiving home-care services in Ontario, Canada. Five themes emerged from the findings: (a) enduring urinary incontinence: "patch it in pads"; (b) struggling to manage diabetes, incontinence, and multiple chronic conditions: "a balancing act"; (c) covering the costs of care: "I can't afford it"; (d) counting on a caregiver: "he does everything"; and (e) home-care services not meeting my needs: "it's not individual." These findings suggest that living with urinary incontinence and diabetes is a complex and challenging experience. This evidence could inform the provision of comprehensive home care to support self-care for this population.

Expandable and implantable bioelectronic complex for analyzing and regulating real-time activity of the urinary bladder

Underactive bladder or detrusor underactivity (DUA), that is, not being able to micturate, has received less attention with little research and remains unknown or limited on pathological causes and treatments as opposed to overactive bladder, although the syndrome may pose a risk of urinary infections or life-threatening kidney damage. Here, we present an integrated expandable electronic and optoelectronic complex that behaves as a single body with the elastic, time-dynamic urinary bladder with substantial volume changes up to ~300%. The system configuration of the electronics validated by the theoretical model allows conformal, seamless integration onto the urinary bladder without a glue or suture, enabling precise monitoring with various electrical components for real-time status and efficient optogenetic manipulation for urination at the desired time. In vivo experiments using diabetic DUA models demonstrate the possibility for practical uses of high-fidelity electronics in clinical trials associated with the bladder and other elastic organs.

Autonomic neuropathy and urologic complications in diabetes

Diabetic autonomic neuropathy affects the entire autonomic nervous system and can lead to dysfunction of the cardiovascular, gastrointestinal, and genitourinary organ systems. Genitourinary dysfunction associated with diabetic autonomic neuropathy includes diabetic bladder dysfunction, sexual dysfunction, and recurrent urinary tract infections. Urological complications in diabetes mellitus are very common; in fact, genitourinary complications are more common than diabetic neuropathy or nephropathy. While several studies have reported on genitourinary dysfunction in individuals with diabetes, UroEDIC, an ancillary study to the Diabetes Control and Complications Trial (DCCT) and its observational follow up, the Epidemiology of Diabetes Interventions and Complications study (EDIC), comprehensively characterized the association between urologic complications and cardiovascular autonomic neuropathy. UroEDIC demonstrated significant associations between autonomic neuropathy and urologic complications in type 1 diabetes, specifically erectile dysfunction, female sexual dysfunction, and lower urinary tract symptoms. In this narrative review, we review the current literature on urological complications in diabetes.

The Pharmacological Mechanism of Diabetes Mellitus-Associated Overactive Bladder and Its Treatment with Botulinum Toxin A

Diabetes mellitus (DM) is an independent risk factor for overactive bladder (OAB). The pathophysiology of DM-associated OAB is multifactorial and time-dependent. Diabetic bladder dysfunction is highly associated with diabetic complications, mainly including diabetic neuropathy and atherosclerosis. Chronic systemic inflammation and bladder urothelial inflammation may contribute to the onset of OAB. Intravesical botulinum toxin A (BoNT-A) injection has proved to be a successful treatment for idiopathic and neurogenic OAB. BoNT-A can inhibit the efferent pathways of the bladder as well as the chronic inflammation and hypersensitivity via the afferent pathways. We conducted a review of the published literature in Pubmed using a combination of two keywords, namely “botulinum toxin A” (BoNT-A) and “overactive bladder”, with or without the additional keywords “detrusor overactivity”, “diabetes mellitus”, “inflammation”, and “urodynamic study”. We also reviewed the experience of our research teams, who have published several studies of the association between DM and OAB. Since limited data support the effectiveness and safety of BoNT-A for treating patients with DM-associated OAB, a comprehensive evaluation of diabetic complications and urodynamic study is needed before treatment. In the future, it is imperative to explore the clinical characteristics and inflammatory biomarkers of diabetes as determining predictors of the treatment efficacy.

Differences between mid-urethral sling outcomes in diabetic and nondiabetic women

AIMS

The aim is to assess whether subjects with diabetes mellitus (DM) have greater urinary retention and increased post-void residual volume (PVR) following mid-urethral sling (MUS) surgery.

METHODS

This multi-center retrospective study included patients who underwent MUS (2012-2016). Baseline data included demographics, comorbidities, urinary symptoms, urodynamics data, PVR, and responses to validated questionnaires (UDI6 and IIQ7). Intraoperative data, postoperative voiding trial results, postop questionnaires, and complications were also noted. Patients with and without DM were compared. Significance was defined as P < .05.

RESULTS

A total of 605 MUS were included, 538(89%) without DM and 67(11%) with DM, of which 69% were transobturator and 31% retropubic. No differences were seen in urinary retention and passing void trial(79% DM vs 81% non-DM; P = .72). Mean PVR at discharge was similar between groups (136 mL DM vs 139 mL non-DM; P = .922). There were no differences between groups in UDI6 and IIQ7 sum scores at baseline and 1 month. DM subjects reported more bother at baseline on certain UDI-6 and IIQ-7 items including frequent urination, leakage related to urgency, and feeling frustrated. At 3 months postop, all subjects demonstrated improvement in scores. Interestingly, patients with DM reported worse quality of life on the IIQ7 sum.

CONCLUSIONS

Among subjects with well-controlled diabetes and more comorbidities who underwent MUS there were few differences in postoperative voiding dysfunction or PVR compared to nondiabetic women. DM patients were more bothered at baseline by urge-related symptoms. Quality of life following sling surgery appears to be worse in patients with DM at 3 months based on IIQ7. This data suggests that diabetic women with lower HbA1C can be counseled similarly to these complication rates and voiding dysfunction after MUS.

Long-term diabetes causes molecular alterations related to fibrosis and apoptosis in rat urinary bladder

Diabetes induces time-dependent alterations in urinary bladders. Long-term diabetes causes an underactive bladder. However, the fundamental mechanisms are still elusive. This study aimed to examine the histological changes and the potential molecular pathways affected by long-term diabetes in the rat bladder. Diabetes was induced in 8-week-old male Lewis rats by streptozotocin, while age-matched control rats received citrate buffer only. Forty-four weeks after diabetes induction, bladders were harvested for histological and molecular analyses. The expressions of proteins related to fibrosis, apoptosis and oxidative stress as well as the cellular signaling pathway in the bladder were examined by immunoblotting. Histological examinations illustrated diabetes caused detrusor hypertrophy and fibrotic changes in the bladder. Immunoblotting analysis demonstrated higher collagen I but lower elastin expression in the bladder in diabetic rats. These were accompanied by an increase in the expression of transforming growth factor-beta1, along with the downregulation of matrix metalloptoteinase-1, and upregulation of tissue inhibitor of metalloproteinase-1. Diabetic rats showed an increase in nitrotyrosine, but decrease in nuclear factor erythroid-related factor 2 (Nrf2) levels in the bladder. Enhanced apoptotic signaling was observed, characterized by increased expression of Bcl-2-associated X protein (Bax), decreased expression of Bcl-2, in the diabetic bladder. The nerve growth factor level was decreased in the diabetic bladder. A significant suppression in the protein expressions of phosphorylated extracellular signal-regulated kinases 1/2 was found in diabetic bladders. This study demonstrated that long-term diabetes caused molecular changes that could promote fibrosis and apoptosis in the bladder. Oxidative stress may be involved in this context.

Relationship between alterations of urinary microbiota and cultured negative lower urinary tract symptoms in female type 2 diabetes patients

Background

Lower urinary tract symptoms (LUTS) is the most common complication of diabetes. However, the underlying pathogenesis of cultured negative LUTS (cn-LUTS) in diabetic patients has not been well understood. Numerous evidence indicates that urinary dysbiosis is related to urologic disorders. We aim to study alterations of the urinary microbiota of cn-LUTS in type 2 diabetes (T2D) patients.

Methods

Female T2D patients and controls were recruited and requested to finish the American Urological Association Symptom Index. Mid-stream urine was collected for culturing and extracting DNA. Microbial diversity and composition were analyzed by targeting to 16S rDNA. Linear discriminant analysis effect size (LEfSe) was carried out to identify significantly different bacteria.

Results

32 female T2D patients and 26 controls were enrolled. No significant differences in alpha diversity were observed between patients and controls. However, statistically decreased richness (ACE index and Chao 1 index, 85.52(13.75, 204.84) vs. 129.82(63.89, 280.30) and 83.86(11.00, 210.77) vs. 125.19(62.00, 251.77), P = 0.005; Observed Species, 76(10, 175) vs. 98(54, 234), P = 0.011) and decreased species diversity (Shannon index, 1.37(0.04, 3.48) vs. 2.09(0.98, 3.43), P = 0.033; Simpson index, 0.46 (0.06, 0.99) vs. 0.23(0.07, 0.64), P = 0.029) were shown in moderate-to-severe LUTS group and high Hemoglobin A1c group, respectively. A significant difference of beta diversity was found between T2D patients and controls and T2D patients with different severity of cn-LUTS as well as the different level of Hemoglobin A1c. LEfSe revealed that 10 genera (e.g., Escherichia-Shigella and Klebsiella) were increased and 7 genera were decreasing in T2D patients, 3 genera (e.g., Escherichia-Shigella and Campylobacter) were increased and 16 genera (e.g., Prevotella) were reduced in moderate-to-severe LUTS group, 2 genera (Escherichia-Shigella and Lactobacillus) were over-represented and 10 genera (e.g., Prevotella) were under-represented in high Hemoglobin A1c group. Finally, Hemoglobin A1c was found positively correlated with the total score of the American Urological Association Symptom Index (r = 0.509, P = 0.003).

Conclusions

Urinary dysbiosis may be related to cn-LUTS in female T2D patients. A better understanding of urinary microbiota in the development and progression of cn-LUTS in female T2D patients was necessary. The severity of cn-LUTS was correlated to hyperglycemia and chronic hyperglycemia might induce or promote cn-LUTS by influencing urinary microbiota.

Electronic supplementary material

The online version of this article (10.1186/s12894-019-0506-0) contains supplementary material, which is available to authorized users.

Administration of human umbilical cord blood mononuclear cells restores bladder dysfunction in streptozotocin-induced diabetic rats

OBJECTIVE

This study evaluated the effect of human umbilical cord blood mononuclear cells (HUCB-MNCs) on bladder dysfunction in streptozotocin (STZ; 35 mg/kg, i.v.)-induced diabetic rats.

METHODS

Adult male Sprague-Dawley rats (n = 30) were equally divided into three groups: control group, STZ-diabetic group, and HUCB-MNC-treated group (1 × 10⁶ cells). HUCB-MNCs were isolated by density gradient centrifugation from eight healthy donors and injected into the corpus cavenosum in STZ-diabetic rats 4 weeks after the induction of diabetes. Studies were performed 4 weeks after HUCB-MNC or vehicle injection. In vitro organ bath studies were performed on bladder strips, whereas protein expression of hypoxia-inducible factor (HIF)-1α, vascular endothelial growth factor (VEGF), and α-smooth muscle actin (SMA) in the bladder and the ratio of smooth muscle cells (SMCs) to collagen were determined using western blotting and Masson trichrome staining.

RESULTS

Neurogenic contractions of detrusor smooth muscle strips were 55% smaller in the diabetic group than control group (P < 0.05); these contractions were normalized by HUCB-MNC treatment. In addition, HUCB-MNC treatment restored the impaired maximal carbachol-induced contractile response in detrusor strips in the diabetic group (29%; P < 0.05). HUCB-MNC treatment improved the KCl-induced contractile response in the diabetic bladder (68%; P < 0.05), but had no effect on ATP-induced contractile responses. Increased expression of HIF-1α and VEGF protein and decreased expression of α-SMA protein and the SMC/collagen ratio in diabetic rats were reversed by HUCB-MNC.

CONCLUSION

Administration of HUCB-MNCs facilitates bladder function recovery, which is likely related to downregulation of HIF-1α expression and attenuation of fibrosis in STZ-diabetic rats.

Novel symptom questionnaire for the differential diagnosis of detrusor underactivity and bladder outlet obstruction in men

OBJECTIVE

To develop a questionnaire for the differential diagnosis of detrusor underactivity (DUA) and bladder outlet obstruction (BOO) without performing invasive pressure flow studies.

STUDY DESIGN AND METHODS

Symptoms of men with DUA were analyzed and compared with those of men with BOO using eight questions from the developing questionnaire. Patients with DUA have a bladder contractility index (PdetQmax+5xQmax) less than 100, whereas those with BOO have a BOO index (PdetQmax-2xQmax) greater than 40 in urodynamic studies (UDS). Men with detrusor overactivity in UDS and neurogenic issues were excluded from the analysis. One urologist reviewed patients' medical records, and responded to eight questions without using information from UDS. Scores in the developing questionnaire were then compared to make a differential diagnosis between DUA and BOO.

RESULTS

Overall, 318 men who underwent UDS were included. Symptoms were compared in patients diagnosed with DUA without BOO (n = 165) and BOO without DUA (n = 153). Questions 1, 2, 4, 5, 6, and 7 were significantly different between groups. The sensitivity and specificity of the questionnaire were 95.8% and 95.4%, respectively, for predicting DUA in patients with scores greater than 45 points (cutoff value).

CONCLUSIONS

Men with DUA and BOO may be distinguished using a developing questionnaire without invasive evaluation. Men with scores greater than 45 points would be expected to have DUA but not BOO.

Detrusor contractility to parasympathetic mediators is differentially altered in the compensated and decompensated states of diabetic bladder dysfunction

Diabetic bladder dysfunction (DBD) affects up to 50% of all patients with diabetes, characterized by symptoms of both overactive and underactive bladder. Although most diabetic bladder dysfunction studies have been performed using models with type 1 diabetes, few have been performed in models of type 2 diabetes, which accounts for ~90% of all diabetic cases. In a type 2 rat model using a high-fat diet (HFD) and two low doses of streptozotocin (STZ), we examined voiding measurements and functional experiments in urothelium-denuded bladder strips to establish a timeline of disease progression. We hypothesized that overactive bladder symptoms (compensated state) would develop and progress into symptoms characterized by underactive bladder (decompensated state). Our results indicated that this model developed the compensated state at 1 wk after STZ and the decompensated state at 4 mo after STZ administration. Diabetic bladders were hypertrophied compared with control bladders. Increased volume per void and detrusor muscle contractility to exogenous addition of carbachol and ATP confirmed the development of the compensated state. This enhanced contractility to carbachol was not due to increased levels of M₃ receptor expression. Decompensation was characterized by increased volume per void, number of voids, and contractility to ATP but not carbachol. Thus, progression from the compensated to decompensated state may involve decreased contractility to muscarinic stimulation. These data suggest that the compensated state of DBD progresses temporally into the decompensated state in the male HFD/STZ model of diabetes; therefore, this male HFD/STZ model can be used to study the progression of DBD.

Suo Quan Wan Protects Mouse From Early Diabetic Bladder Dysfunction by Mediating Motor Protein Myosin Va and Transporter Protein SLC17A9

Objective: To investigate the effects of Suo Quan Wan (SQW), a traditional Chinese herbal formula, on the overactive bladder (OAB) of type 2 diabetes mellitus (T2DM) mouse models, particularly on its function of mediating the gene and protein expression levels of myosin Va and SLC17A9.

Materials and Methods: After 4 weeks high-fat diet (HFD) feeding, C57BL/6J mice were injected with streptozotocin (100 mg/kg) for four times. After 3 weeks, the diabetic mice were treated with SQW for another 3 weeks. Voided stain on paper assay, fasting blood glucose (FBG) test, and oral glucose tolerance test (OGTT) were conducted. Urodynamic test, tension test [α,β-methylene ATP, electrical-field stimulation (EFS), KCl, and carbachol] and histomorphometry were also performed. Western blot analysis and qPCR assays were used to quantify the expression levels of myosin Va and SLC17A9.

Results: The diabetic mice exhibited decreased weight but increased water intake, urine production, FBG, and OGTT. No significant changes were observed after 3 weeks SQW treatment. Urodynamic test indicated that the non-voiding contraction (NVC) frequency, maximum bladder capacity (MBC), residual volume (RV), and bladder compliance (BC) were remarkably increased in the diabetic mice, whereas the voided efficiency (VE) was decreased as a feature of overactivity. Compared with the model mice, SQW treatment significantly improved urodynamic urination with decreased NVC, MBC, RV, and BC, and increased VE. Histomorphometry results showed that the bladder wall of the diabetic mice thickened, and SQW effectively attenuated the pathological alterations. The contract responses of bladder strips to all stimulators were higher in the DSM strips of diabetic mice, whereas SQW treatment markedly decreased the contraction response for all stimuli. Moreover, the protein and gene expression levels of myosin Va and SLC17A9 were up-regulated in the bladders of diabetic mice, but SQW treatment restored such alterations.

Conclusion: T2DM mice exhibited the early phase of diabetic bladder dysfunction (DBD) characterized by OAB and bladder dysfunction. SQW can improve the bladder storage and micturition of DBD mice by mediating the protein and gene expression levels of myosin Va and SLC17A9 in the bladder, instead of improving the blood glucose level.

Time-dependent functional, morphological, and molecular changes in diabetic bladder dysfunction in streptozotocin-induced diabetic mice

Aim

Diabetic bladder dysfunction (DBD) is one of the most common and bothersome complications of diabetes mellitus (DM). This study aimed to investigate the functional, structural, and molecular changes of the bladder at 0, 3, 6, 9, and 12 weeks after DM induction by streptozotocin (STZ) in male C57BL/6 mice.

Methods

Male C57BL/6J mice were injected with STZ (130 mg/kg). Then, diabetic general characteristics, cystometry test, histomorphometry, and contractile responses to α, β‐methylene ATP, KCl, electrical‐field stimulation, carbachol were performed at 0, 3, 6, 9, and 12 weeks after induction. Finally, protein and messenger RNA (mRNA) expressions of myosin Va and SLC17A9 were quantified.

Results

DM mice exhibited lower body weight, voiding efficiency and higher water intake, urine production, fasting blood glucose, oral glucose tolerance test, bladder wall thickness, maximum bladder capacity, residual volume, bladder compliance. In particular, nonvoiding contractions has increased more than five times at 6 weeks. And the amplitudes of spontaneous activity, contractile responses to all stimulus was about two times higher at 6 weeks but cut almost in half at 12 weeks. The protein and mRNA expressions of myosin Va and SLC17A9 were about two times higher at 6 weeks, but myosin Va was reverted nearly 40% while SLC17A9 is still higher at 12 weeks.

Conclusions

DBD transitioned from a compensated state to a decompensated state in STZ‐induced DM mice at 9 to 12 weeks after DM induction. Our molecular data suggest that the transition may be closely related to the alterations of myosin Va and SLC17A9 expression levels in the bladder with time.

Effects of Radix Linderae extracts on a mouse model of diabetic bladder dysfunction in later decompensated phase

Background

This study aimed to elucidate the effects and mechanisms of Radix Linderae (RL) extracts on a mouse model of diabetic bladder dysfunction (DBD), especially on later decompensated phase.

Methods

Male C57BL/6J mice were intraperitoneally injected with streptozotocin (STZ) after 4 weeks of high-fat diet (HFD) feeding. DBD mouse models (later decompensated phase) were developed by 12-weeks persistent hyperglycemia and then treated with RL extracts for 4 weeks. During administration, the fasting blood glucose (FBG) test was performed once a week. Four weeks later, oral glucose tolerance test (OGTT), voided stain on paper (VSOP), and urodynamic alteration were explored. We also performed haematoxylin and eosin (H&E) and Masson’s trichrome staining to observe the histology of the bladder. Then, the contractile responses to α, β-methylene ATP, capsaicin (CAP), KCl and carbachol were measured. Moreover, qPCR assay was performed to analyse the bladder gene expression levels of M₃ receptors and TRPV1.

Results

The diabetic mice exhibited higher FBG, OGTT and urine production, and no substantial alteration was observed after RL treatment. Urodynamic test showed the maximum bladder capacity (MBC), residual volume (RV) and bladder compliance (BC), as well as the decrement of voided efficiency (VE) and micturition volume (MV), remarkably increased in the DBD mice. Furthermore, RL treatment significant improved urodynamic urination, with lower MBC, RV, and, BC, as well as higher VE and MV, as compared with the model groups. The wall thickness of the bladder and the ratio of smooth muscle/collagen remarkably increased, and RL could effectively attenuate the pathological change. The response of bladder strips to the stimulus was also reduced in the DBD mice, and RL treatment markedly increased the contraction. Furthermore, the gene expression levels of M₃ receptors and TRPV1 were down-regulated in the bladders of the diabetic mice, whereas RL treatment retrieved those gene expression levels.

Conclusions

RL extracts can improve the bladder voiding functions of the DBD model mice in later decompensated phase, and underlying mechanisms was associated with mediating the gene expression of M₃ receptors and TRPV1 in the bladder instead of improving blood sugar levels.

Electronic supplementary material

The online version of this article (10.1186/s12906-019-2448-1) contains supplementary material, which is available to authorized users.

NLRP3 Promotes Diabetic Bladder Dysfunction and Changes in Symptom-Specific Bladder Innervation

The NLRP3 inflammasome senses diabetic metabolites and initiates inflammation implicated in diabetic complications and neurodegeneration. No studies have investigated NLRP3 in diabetic bladder dysfunction (DBD), despite a high clinical prevalence. In vitro, we found that numerous diabetic metabolites activate NLRP3 in primary urothelial cells. In vivo, we demonstrate NLRP3 is activated in urothelia from a genetic type 1 diabetic mouse (Akita) by week 15. We then bred an NLRP3^-/- genotype into these mice and found this blocked bladder inflammation and cystometric markers of DBD. Analysis of bladder innervation established an NLRP3-dependent decrease in overall nerve density and Aδ-fibers in the bladder wall along with an increase in C-fiber populations in the urothelia, which potentially explains the decreased sense of bladder fullness reported by patients and overactivity detected early in DBD. Together, the results demonstrate the role of NLRP3 in the genesis of DBD and suggest specific NLRP3-mediated neuronal changes can produce specific DBD symptoms.

Association between Sarcopenia and Overactive Bladder in Elderly Diabetic Patients

OBJECTIVES

To determine the association between sarcopenia and overactive bladder (OAB) in elderly diabetic patients using the Japanese version of SARC-F called SARC-F-J.

DESIGN

Cross-sectional study.

SETTINGS AND PARTICIPANTS

The study included 329 elderly diabetic patients (aged ≥65 years) who regularly visited the outpatient clinic at Community hospital in Japan.

MEASUREMENTS

The condition of OAB was evaluated using the OAM symptom score, which involves a self-administered questionnaire, and sarcopenia was evaluated using the self-administered SARC-F-J questionnaire comprising five items. The odds ratio for OAB due to sarcopenia was calculated using multiple logistic regression analysis, with OAB as the dependent variable and sarcopenia as the explanatory variable.

RESULTS

A total of 329 patients (186 males, 143 females) were included for analysis in the present study. Of these patients, 22.9% had sarcopenia and 18.7% had OAB. After adjusting the variables, the odds ratio for OAB due to sarcopenia was 4.46 (95% confidence interval [CI], 1.14-17.36, P = 0.031) and 2.09 (95% CI, 0.52-8.26, P = 0.293) for males and females, respectively.

CONCLUSION

This study found that sarcopenia was significantly associated with OAB in elderly diabetic male patients based on SARC-F-J. Moreover, the possibility of the development of OAB should be considered during the medical examinations of elderly diabetic male patients with sarcopenia.

Urothelial Senescence in the Pathophysiology of Diabetic Bladder Dysfunction-A Novel Hypothesis

Diabetic bladder dysfunction (DBD) is a well-recognized and common symptom affecting up to 50% of all diabetic patients. DBD has a broad range of clinical presentations ranging from overactive to underactive bladder symptoms that develops in middle-aged to elderly patients with long standing and poorly controlled diabetes. Low efficacy of current therapeutics and lifestyle interventions combined with high national healthcare costs highlight the need for more research into bladder dysfunction pathophysiology and novel treatment options. Cellular senescence is an age-related physiologic process in which cells undergo irreversible growth arrest induced by replicative exhaustion and damaging insults. While controlled senescence negatively regulates cell proliferation and promotes tissue regeneration, uncontrolled senescence is known to result in tissue dysfunction through enhanced secretion of inflammatory factors. This review presents previous scientific findings and current hypotheses that characterize diabetic bladder dysfunction. Further, we propose the novel hypothesis that cellular senescence within the urothelial layer of the bladder contributes to the pro-inflammatory/pro-oxidant environment and symptoms of diabetic bladder dysfunction. Our results show increased cellular senescence in the urothelial layer of the bladder; however, whether this phenomenon is the cause or effect of DBD is unknown. The urothelial layer of the bladder is made up of transitional epithelia specialized to contract and expand with demand and plays an active role in transmission by modulating afferent activity. Transition from normal functioning urothelial cells to secretory senescence cells would not only disrupt the barrier function of this layer but may result in altered signaling and sensation of bladder fullness; dysfunction of this layer is known to result in symptoms of frequency and urgency. Future DBD therapeutics may benefit from targeting and preventing early transition of urothelial cells to senescent cells.