Measuring urinary 8-hydroxy-2'-deoxyguanosine and malondialdehyde levels in women with overactive bladder

Urine biomarker could be a useful tool for differential diagnosis of a lower urinary tract dysfunction

A precision diagnosis of lower urinary tract dysfunctions (LUTD) such as bladder outlet obstruction, detrusor overactivity (DO), interstitial cystitis/bladder pain syndrome (IC/BPS), dysfunctional voiding (DV), or detrusor underactivity (DU) needs invasive videourodynamic study. Exploring non-invasive tools to help screening LUTD is necessary for clinicians in their daily practice. This article reviews recently clinical studies of using urinary inflammatory proteins and oxidative stress biomarkers in the identification of specific LUTD among men and women with lower urinary tract symptoms (LUTS). Some important findings have been reported: (1) Using urine chemokines CXCL-1 and interleukin-8 (IL-8), we may discriminate overactive bladder (OAB) symptoms in women between DO and urinary tract infection. (2) Urinary levels of oxidative stress biomarkers such as 8-hydroxydeoxyguanosine (8-OHdG) and 8-isoprostane have a potential being used as a tool to identify women with mixed DO and stress urinary incontinence. (3) Urine levels of total antioxidant capacity (TAC), and prostaglandin E2 (PGE2) are positively correlated with voiding detrusor pressure in patients with DU. (4) Urine levels of brain-derived neurotrophic factor (BDNF) and PGE2 were significantly higher in the DU patients with detrusor function recovery. (5) Women with DV had higher urinary levels of tumor necrosis factor-alpha (TNF-α) and 8-OHdG, and urinary IL-2 level was significantly lower. (6) Urine level of 8-isoprostane was higher in the patients with idiopathic DO and neurogenic DO. (7) Higher urine cytokine levels of monocyte chemoattractant protein-1 (MCP-1), regulated on activation, normal T-cell expressed and secreted (RANTES), CXCL-10, IL-7, and eotaxin-1 in patients with IC/BPS than controls. (8) The urine levels of IL-8, CXCL-10, BDNF, IL-6, and RANTES were significantly higher in patients with Hunner's IC than non-Hunner's IC. (9) Male patients with IC/BPS had a significantly higher level of eotaxin, MCP-1, TNF-α, 8-OHdG, and TAC. Combining a higher eotaxin and a higher TNF-α can provide a satisfactory diagnostic value in discriminating IC/BPS from other LUTD in men. These studies provide evidence that measurement of cluster of urine biomarkers could be used as a diagnostic tool to differentiate different LUTD in patients with similar LUTS.

Vitamin D levels and the risk of overactive bladder: a systematic review and meta-analysis

CONTEXT

Overactive bladder is treated mainly with behavioral and drug therapy, and symptoms of urinary frequency and incontinence are challenging to eliminate. There is thus a continuous unmet need for new drugs with a substitution effect mechanism.

OBJECTIVE

It not known whether vitamin D deficiency can lead to overactive bladder or urinary incontinence or whether vitamin D supplementation alleviates bladder symptoms. This comprehensive systematic review with meta-analysis was conducted to determine whether overactive bladder is associated with vitamin D deficiency.

DATA SOURCES

The PubMed and Cochrane Library databases were searched systematically up to July 3, 2022.

DATA EXTRACTION

Initially, 706 articles were identified in the literature search, of which 13 were included in the systematic review: 4 randomized controlled trials, 3 cohort studies, 3 cross-sectional studies, and 3 case-control studies.

DATA ANALYSIS

An increased risk of overactive bladder and urinary incontinence was observed with vitamin D deficiency (odds ratio [OR] = 4.46; 95%CI, 1.03-19.33; P = 0.046 and OR = 1.30; 95%CI, 1.01-1.66; P = 0.036, respectively). Vitamin D levels were relatively low in patients with overactive bladder or urinary incontinence (SMD = -0.33; 95%CI, -0.61 to -0.06, P = 0.019). On the basis of existing data, the risk of urinary incontinence was reduced by 66% after vitamin D supplementation (OR = 0.34; 95%CI, 0.18-0.66; P = 0.001). Egger test was conducted to assess publication bias, and the results were tested for robustness using a sensitivity analysis.

CONCLUSIONS

Vitamin D deficiency increases the risk of overactive bladder and urinary incontinence, and vitamin D supplementation reduces the risk of urinary incontinence. The development of new strategies to prevent or alleviate bladder symptoms is crucial. Vitamin D supplementation may be gaining recognition as an effective strategy for prevention or alleviation of bladder symptoms such as overactive bladder and incontinence.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO registration no. CRD42022351443.

Urinary Oxidative Stress Biomarker Levels Might Be Useful in Identifying Functional Bladder Disorders in Women with Frequency and Urgency Syndrome

Purpose: lower urinary tract dysfunctions (LUTDs) are difficult to diagnose based on symptoms. This study used a cluster of urinary biomarkers, including inflammatory cytokines, neurogenic proteins, and oxidative stress biomarkers, to identify LUTDs in women with frequency and urgency symptoms. Methods: in total, 253 women with video urodynamics (VUDS)- and cystoscopy-confirmed detrusor overactivity (DO), interstitial cystitis/bladder pain syndrome (IC/BPS), dysfunctional voiding (DV), and hypersensitive bladder (HSB), and normal controls were included. Before diagnosis and treatment, urine samples were collected for analysis of biomarkers. The urine levels of biomarkers were compared between groups with bladder dysfunctions and controls and were combined to test the sensitivity in identifying total pathological bladder diseases and specific bladder diseases. Results: After video urodynamic study, VUDS, and urological examinations, bladder dysfunctions were classified into DO (n = 31), IC/BPS (n = 114), DV (n = 45), HSB (n = 29), and control (n = 34) groups. By using a cystomeric bladder capacity of ≤350 mL, 186/219 (84.9%) of the patients with DO, IC/BPS, DV, and HSB can be discriminated from the controls. Among these urine biomarkers, oxidative stress biomarkers 8-isoprostane, 8-hydroxydeoxyguanosine (8-OHdG), or total antioxidant capacity (TAC) are useful for identifying pathological bladder dysfunction (DO, IC/BPS, and DV) and HSB. With elevated IL-1β and lower IL-2, and elevated TNF-α levels, most patients with DV can be identified. Between DO and IC/BPS, a higher NGF level can identify 58.3% of IC/BPS cases, whereas a lower NGF level can identify 75.0% of DO cases. Conclusion: by using a cluster of urine biomarkers, DO, IC/BPS, and DV cases can be identified based on elevated levels of urine oxidative stress biomarkers 8-isoprostane, TAC, or 8-OHdG, and HSB cases with a low TAC. These urine biomarkers are useful for identifying specific LUTDs in women with frequency and urgency symptoms.

Discriminating Different Bladder and Bladder Outlet Dysfunctions by Urinary Biomarkers in Women with Frequency–Urgency Syndrome

Objectives: To investigate the role of urinary biomarkers in discriminating different bladder and bladder outlet dysfunctions in women with frequency–urgency syndrome. Materials and Methods: Urine samples collected from 146 women with frequency–urgency syndrome and 34 controls were investigated. All patients were included in previous clinical trials of functional urology studies and underwent a videourodynamic study. Patients with frequency–urgency syndrome were subdivided into idiopathic detrusor overactivity (IDO), neurogenic detrusor overactivity (NDO), dysfunctional voiding (DV), and hypersensitive bladder (HSB) subgroups. Urine samples were collected before any treatment, and urinary inflammatory proteins (interleukin- (IL-) 1β, IL-2, IL-6, IL-8, tumor necrosis factor-α (TNF-α), and vascular endothelial growth factor (VEGF)), neurogenic proteins (nerve growth factor (NGF), brain-derived neurotrophic factor (BDNF), and prostaglandin E2 (PGE2)), and oxidative stress biomarkers (8-isoprostane, total antioxidant capacity (TAC), and 8-hydroxydeoxyguanosine (8-OHdG)) were measured and compared between the different OAB subgroups and controls. Results: Of the 146 patients, 31 had IDO, 41 had NDO, 45 had DV, and 29 had HSB. The control group included 34 women. The patients with HSB had lower urinary TAC and IL-2 levels than the controls. The patients with IDO, NDO, and DV had significantly higher urinary TNF-α levels than those with HSB. The patients with IDO and NDO showed an increase in the urinary 8-isoprostane levels, whereas the patients with IDO had higher urinary IL-2, NGF, and BDNF levels than those with NDO. The other urinary inflammatory biomarkers did not show enough significant differences to discriminate between the different bladder and bladder outlet dysfunctions. Conclusions: The urinary levels of inflammatory, neurogenic, and oxidative stress biomarkers varied widely among the patients with bladder and bladder outlet dysfunction. This study’s results provide evidence that women with frequency–urgency syndrome and different urodynamic subtypes have varying bladder inflammation and oxidative stress conditions, which might have an impact on treatment outcomes.

Feline Uroepithelial Cell Culture as a Novel Model of Idiopathic Cystitis: Investigations on the Effects of Norepinephrine on Inflammatory Response, Oxidative Stress, and Barrier Function

Feline idiopathic cystitis (FIC) is one of the most common urinary tract disorders in domestic cats. As stress is suggested to play a key role in the pathogenesis of FIC, the effects of norepinephrine (NE) as a stress mediator were investigated on a novel feline primary uroepithelial cell culture, serving as an in vitro model of the disease. The uroepithelial cells gained from the mucosa of the bladder of a euthanized cat were cultured for 6 days and were acutely exposed to NE (10, 100, and 1000 µM) for 1 h. NE increased the metabolic activity of the cultured cells and elevated the extracellular concentrations of the pro-inflammatory mediators interleukin-6 (IL-6) and stromal cell derived factor 1 (SDF-1), confirming that NE can trigger an inflammatory response in the uroepithelium. Cellular protein carbonyl levels were increased by NE exposure, while malondialdehyde and glucose regulated protein 78 concentrations remained unchanged, indicating that NE may provoke the oxidative damage of proteins without inducing lipid peroxidation or endoplasmic reticulum stress. Further, it can be strongly suggested that an acute NE challenge might diminish the barrier function of uroepithelial cells, as reflected by the decreased glycosaminoglycan concentration, claudin-4 protein expression, and reduced TER values of the NE-treated cell cultures. Based on these results, short-term NE exposure mimicking acute stress can provoke an inflammatory response and decrease the barrier integrity of cultured feline uroepithelial cells. Hence, it is highly expected that stress-associated NE release may play an important mediatory role in the pathogenesis of FIC.

Urinary Oxidative Stress Biomarkers in the Diagnosis of Detrusor Overactivity in Female Patients with Stress Urinary Incontinence

Ninety-three women with urodynamic stress incontinence (USI) and a mean age of 60.8 ± 10.7 (36-83) years were retrospectively enrolled. According to their VUDS, 31 (33%) were grouped into USI and detrusor overactivity (DO), 28 (30.1%) were grouped into USI and hypersensitive bladder (HSB), and 34 (36.6%) were controls (USI and stable bladder). The USI and DO group had significantly increased 8-isoprostane (mean, 33.3 vs. 10.8 pg/mL) and 8-hydroxy-2-deoxyguanosine (8-OHdG; mean, 28.9 vs. 17.4 ng/mL) and decreased interleukin (IL)-2 (mean, 0.433 vs. 0.638 pg/mL), vascular endothelial growth factor (mean, 5.51 vs. 8.99 pg/mL), and nerve growth factor (mean, 0.175 vs. 0.235 pg/mL) levels compared to controls. Oxidative stress biomarkers were moderately diagnostic of DO from controls, especially 8-isoprostane (area under the curve (AUC) > 0.7). Voided volume was highly diagnostic of DO from either controls or non-DO patients (AUC 0.750 and 0.915, respectively). The proposed prediction model with voided volume, 8-OHdG, and 8-isoprostane (cutoff values 384 mL, 35 ng/mL, and 37 pg/mL, respectively) had an accuracy of 81.7% (sensitivity, 67.7%; specificity, 88.7%; positive predictive value, 75.0%; negative predictive value, 84.6%). Combined with voided volume, urinary oxidative stress biomarkers have the potential to be used to identify urodynamic DO in patients with USI.

Bladder Hyperactivity Induced by Oxidative Stress and Bladder Ischemia: A Review of Treatment Strategies with Antioxidants

Overactive bladder (OAB) syndrome, including frequency, urgency, nocturia and urgency incontinence, has a significantly negative impact on the quality-of-life scale (QoL) and can cause sufferer withdrawal from social activities. The occurrence of OAB can result from an imbalance between the production of pro-oxidants, such as free radicals and reactive species, and their elimination through protective mechanisms of antioxidant-induced oxidative stress. Several animal models, such as bladder ischemia/reperfusion (I/R), partial bladder outlet obstruction (PBOO) and ovarian hormone deficiency (OHD), have suggested that cyclic I/R during the micturition cycle induces oxidative stress, leading to bladder denervation, bladder afferent pathway sensitization and overexpression of bladder-damaging molecules, and finally resulting in bladder hyperactivity. Based on the results of previous animal experiments, the present review specifically focuses on four issues: (1) oxidative stress and antioxidant defense system; (2) oxidative stress in OAB and biomarkers of OAB; (3) OAB animal model; (4) potential nature/plant antioxidant treatment strategies for urinary dysfunction with OAB. Moreover, we organized the relationships between urinary dysfunction and oxidative stress biomarkers in urine, blood and bladder tissue. Reviewed information also revealed the summary of research findings for the effects of various antioxidants for treatment strategies for OAB.

Potential contribution of ELISA and LFI assays to assessment of the oxidative stress condition based on 8-oxodG biomarker

Immunoassays have been extensively applied in the medical diagnostic field. Enzyme-Linked Immunosorbent Assay (ELISA) and Lateral Flow Immunochemical Assay (LFIA) are methods that have been well established to analysis of clinical substances such as protein, hormones, drugs, identification of antibodies and in the quantification of antigen. Over the past years, the application of these methods has been extended to assess the clinical oxidative stress condition based on monitoring of the 8-oxo-7,8-dihydro-2'-deoxyguanosine (8-oxodG) biomarker levels. The present manuscript provides an overview of the current immunoassays based on ELISA and LFIA technologies applied for a quantitative analysis of the 8-oxodG. The discussion focuses on the principles of development, improvement and analytical performance of these assays. The relationship of the molecule 8-oxodG as a clinical biomarker of the assessment of the oxidative stress condition is also discussed. Commercially available products to 8-oxodG analysis are also presented.

Isoprostanes evoke contraction of the murine and human detrusor muscle via activation of the thromboxane prostanoid TP receptor and Rho kinase

Local or systemic inflammation can severely impair urinary bladder functions and contribute to the development of voiding disorders in millions of people worldwide. Isoprostanes are inflammatory lipid mediators that are upregulated in the blood and urine by oxidative stress and may potentially induce detrusor overactivity. The aim of the present study was to investigate the effects and signal transduction of isoprostanes in human and murine urinary bladders in order to provide potential pharmacological targets in detrusor overactivity. Contraction force was measured with a myograph in murine and human urinary bladder smooth muscle (UBSM) ex vivo. Isoprostane 8-iso-PGE₂ and 8-iso-PGF_2α evoked dose-dependent contraction in the murine UBSM, which was abolished in mice deficient in the thromboxane prostanoid (TP) receptor. The responses remained unaltered after removal of the mucosa or incubation with tetrodotoxin. Smooth muscle-specific deletion of Gα_12/13 protein or inhibition of Rho kinase by Y-27632 decreased the contractions. In Gα_q/11-knockout mice, responses were reduced and in the presence of Y-27632 abolished completely. In human UBSM, the TP agonist U-46619 evoked dose-dependent contractions. Neither atropine nor the purinergic receptor antagonist pyridoxalphosphate-6-azophenyl-2',4'-disulfonic acid decreased the effect, indicating that TP receptors directly mediate detrusor muscle contraction. 8-iso-PGE₂ and 8-iso-PGF_2α evoked dose-dependent contraction in the human UBSM, and these responses were abolished by the TP antagonist SQ-29548 and were decreased by Y-27632. Our results indicate that isoprostanes evoke contraction in murine and human urinary bladders, an effect mediated by the TP receptor. The G_12/13-Rho-Rho kinase pathway plays a significant role in mediating the contraction and therefore may be a potential therapeutic target in detrusor overactivity.NEW & NOTEWORTHY Voiding disorders affect millions of people worldwide. Inflammation can impair urinary bladder functions and contribute to the development of detrusor overactivity. The effects and signal transduction of inflammatory lipid mediator isoprostanes were studied in human and murine urinary bladders ex vivo. We found that isoprostanes evoke contraction, an effect mediated by thromboxane prostanoid receptors. The G_12/13-Rho-Rho kinase signaling pathway plays a significant role in mediating the contraction and therefore may be a potential therapeutic target.

Hematological and Hepatic Effects of Ulexite in Zebrafish

The ulexite (UX), a borate mineral, is used as boron source and commonly used in various industrial processes. The hematological and hepatic effects of UX were investigated by exposing adult zebrafish to UX (5, 10, 20 and 40 mg/L) over 96 hours. The blood and liver tissues were taken at the end of the trial period then micronucleus (MN) rates, oxidative DNA damage (8-OHdG), apoptosis (Caspase-3), superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx), myeloperoxidase (MPO), paraoxonase (PON), arylesterase (AR) and lipid peroxidation (MDA) levels were determined. Genotoxic damage by UX occurred only at 40 mg/L in the blood MN assay. Oxidative stress, oxidative DNA damage and apoptosis in liver also occurred at this dose. Moreover, 5-20 mg/L doses led to decreases of DNA damage and apoptosis levels via promoting antioxidant system in liver tissues. UX exhibits beneficial roles on blood and liver tissues of zebrafish at relatively lower doses, which may be relevant to nutritional and medicinal industries.

The profile of urinary biomarkers in overactive bladder

AIMS

In overactive bladder (OAB) research, different biomarkers have been proposed as diagnostic tools and may be used to create individual patient profiles. Assessing the diagnostic performance of biomarkers would better outline their utility. Therefore, our aim was to investigate the diagnostic value of four urinary biomarkers: human brain derived neurotrophic factor (hBDNF), malondialdehyde (MDA), h nerve growth factor (hNGF) and h 8-hydroxydeoxyguanosine in women with OAB. These are neurotrophins/oxidative stress markers that have been linked to lower urinary tract symptoms.

METHODS

A total of 105 women were included in the study and distributed in two groups: a group with OAB (n = 53) and a control group (n = 50). The levels of the biomarkers were determined using enzyme-linked immunosorbent assay technique and they were compared between the groups. If the Mann-Whitney test demonstrated a statistically significant difference, receiver operating curves (ROC) analysis was undertaken.

RESULTS

When normalized to urinary creatinine, hBDNF, MDA, and hNGF showed significantly increased values in women with OAB as compared to controls, whereas 8-OHdG showed no significant difference. The diagnostic performance of these biomarkers was analyzed based on the area under the ROC curve (AUC). MDA had the highest AUC (0.75), followed by hNGF (0.69) and hBDNF (0.67).

CONCLUSIONS

Our findings suggest that MDA, a relatively novel biomarker in OAB research, has a fair performance as a diagnostic tool for OAB. Moreover, urinary neurotrophins (NGF and BDNF) as biomarkers may have a role in the diagnostic pathways of women with OAB symptoms.

Outcomes Assessment of Sustainable and Innovatively Simple Lifestyle Modification at the Workplace - Drinking Electrolyzed-Reduced Water (OASIS-ERW): A Randomized, Double-Blind, Placebo-Controlled Trial

Oxidative stress has been associated with many diseases as well as aging. Electrolyzed-reduced water (ERW) has been suggested to reduce oxidative stress and improve antioxidant potential. This study investigated the effects of drinking ERW on biomarkers of oxidative stress and health-related indices in healthy adults. We conducted a randomized, double-blind, placebo-controlled clinical trial on 65 participants, who were allocated into two groups. Of these, 61 received intervention (32 with ERW and 29 MW [mineral water]). All participants were instructed to drink 1.5 L/day of ERW or MW for eight weeks. Biomarkers of oxidative stress and health-related indices were assessed at baseline as well as after 4 weeks and 8 weeks of intervention. Of the primary outcome variables assessed, diacron-reactive oxygen metabolites (d-ROMs) and biological antioxidant potential showed a significant interaction between the groups and time, with d-ROMs levels significantly decreased at 8 weeks in ERW compared to those in MW. Among the secondary outcome variables, total, visceral, and subcutaneous fat mass significantly changed over time, with a significant association observed between the groups and time. Thus, daily ERW consumption may be a potential consideration for a sustainable and innovatively simple lifestyle modification at the workplace to reduce oxidative stress, increase antioxidant potential, and decrease fat mass.

Vitamin D and thiol-disulfide homeostasis levels in postmenopausal women with overactive bladder syndrome

Background

This study aimed to find a relationship between vitamin D concentration and thiol-disulfide homeostasis in the pathophysiology of overactive bladder (OAB) syndrome in postmenopausal women.

Methods

A total of 76 postmenopausal women, referred for routine controls, were recruited between January and March 2018 to participate in this study. Participants with an overactive bladder questionnaire (OAB-q) score of >11 (n = 34) were included in the OAB syndrome group, while those with a score of <5 (n = 42) were included in the control group. Serum total antioxidant capacity, ischemia-modified albumin, C-reactive protein, 25-hydroxy vitamin D levels, and thiol-disulfide homeostasis were measured.

Results

Patients with OAB syndrome had waist circumferences of 106 ± 11 cm, and their body mass indexes (BMIs) were 30.8 ± 4.8 kg/m2. The control groups' waist circumferences were 102 ± 11 cm and their BMIs were 28.9 ± 4.3 kg/m2 (p = 0.069 and p = 0.098, respectively). The level of vitamin D in the control group was 33.7 (IQR: 30.7) nmol/L and 27.0 (IQR: 27.5) nmol/L (p = 0.081) in the OAB syndrome group.

Conclusions

We were not able to demonstrate with certainty any significant relationships between serum 25-hydroxy vitamin D levels and thiol-disulfide homeostasis parameters and OAB syndrome.