Quality of Life and Treatment Modalities in Patients with Interstitial Cystitis: The Patients' Perspective.

BACKGROUND: Quality of life (QoL)-based outcomes are hardly incorporated into interstitial cystitis/bladder pain syndrome (IC/BPS) guidelines, because studies are limited and outdated. Therefore, guidelines might not reflect the current clinical situation accurately. Secondly, guidelines suggest using a multimodal approach for BPS/IC management, but data on the patient-perceived efficacy of these therapies are limited. The aim of this study is to investigate the perception of IC/BPS patients of their QoL, to determine which treatments they have received, and to examine how they evaluate the efficacy of these various (alternative) therapies. METHODS: A quantitative retrospective database evaluation was performed, with data from an existing IC/BPS patient survey (n = 217) that was conducted in 2021. This survey contained QoL data based on validated questionnaires such as EQ-5D 5L. RESULTS: The QoL of patients is affected significantly by IC/BPS. This is evident from the various affected domains on the EQ-5D 5L. The symptom severity was negatively affected by a delay in diagnosis, and there were clear differences in QoL domains between females and males. Secondly, coagulation therapy and intravesical glycosaminoglycan (GAG) therapy were most appreciated by patients. Other (alternative) treatments were commonly utilized, although some had doubtful results and high discontinuation rates. CONCLUSION: QoL is considerably impaired in IC/BPS patients. The diverse responses and adherence to various treatments warrant a personalized approach (phenotype-oriented therapy). To achieve QoL improvement, it is important to incorporate the patient's perspective in treatment guidelines.

The urothelial barrier in interstitial cystitis/bladder pain syndrome: its form and function, an overview of preclinical models.

PURPOSE OF REVIEW: Investigating bladder pain syndrome/interstitial cystitis (IC/BPS) preclinically is challenging. Various research models have been used to mimic the urothelial barrier closely and replicate the disease. The aim of this review is to discuss preclinical research related to the urothelial barrier in context of IC/BPS. RECENT FINDINGS: In vivo models mimic IC/BPS mainly with toxic substances in the urine, with protaminesulfate and proteoglycan deglycolysation resembling a temporary impaired barrier as seen in IC/BPS. This temporary increased permeability has also been found in vitro models. Glycosaminoglycan replenishment therapy has been described, in vivo and in vitro, to protect and enhance recover properties of the urothelium. The roles of immune and neurogenic factors in the pathogenesis of IC/BPS remains relatively understudied. SUMMARY: Preclinical studies provide opportunities to identify the involvement of specific pathologic pathways in IC/BPS. For further research is warranted to elucidate the primary or secondary role of permeability, together with inflammatory and neurogenic causes of the disease.

The Burden of Urinary Tract Infections on Quality of Life and Healthcare in Patients with Interstitial Cystitis.

BACKGROUND: Interstitial cystitis/bladder pain syndrome (IC/BPS) patients are more susceptible to urinary tract infections (UTIs), likely worsening pre-existing symptoms. However, this receives limited attention in guidelines. This study aimed to explore the burden of UTIs on IC/BPS patients' quality of life and their healthcare. METHODS: Two quantitative retrospective database studies were conducted in cystoscopically proven IC/BPS patients: one compiled existing patient survey data (n = 217) from July 2021 to examine physical and emotional UTI burden, and the other used a patient file database (n = 100) from January 2020 to May 2022, focusing on UTI prevalence, healthcare use, urine cultures and antibiotic resistance. RESULTS: A delay in diagnosis was seen in 70% of patients, due to doctors confusing IC/BPS symptoms with UTIs. The UTI prevalence was over 50%; these patients also report anxiety for new UTIs (70%) and worsening of IC/BPS symptoms (60%). Additionally, for UTI+ patients, healthcare consumption was significantly increased in both studies. Antibiotic resistance (80% of cultures) and prophylactic antibiotic use were common. CONCLUSIONS: These findings highlight the burden of UTIs on quality of life in IC/BPS patients and the healthcare system. These results emphasize the need for improved UTI guidelines concerning diagnosis, management and prevention for IC/BPS patients to improve quality of life and care.

Differences in the Urinary Microbiome of Patients with Overactive Bladder Syndrome with and without Detrusor Overactivity on Urodynamic Measurements.

INTRODUCTION: It has been hypothesized that the urinary microbiome might play an important role in OAB. Studies have been conducted on the association between OAB symptoms and the microbiome, although a possible causality still has to be determined. MATERIAL AND METHODS: In this study, 12 female patients, ≥18 years of age, with 'OAB DO+' and 9 female patients with 'OAB DO-' were included. Patients were excluded if they met one of the following exclusion criteria: bladder tumors and previous bladder operations; sacral neuromodulation; injection of Botox in the bladder; and TOT or TVT operations. Urine samples were collected and stored with patient informed consent and with the approval of the Hospital Ethical Review Board (Arnhem-Nijmegen). All OAB patients underwent urodynamics before collecting urine samples, and the diagnosis of detrusor overactivity was confirmed by two individual urologists. In addition, samples from 12 healthy controls who did not undergo urodynamic evaluation were analyzed. The 16S rRNA V1-V2 region amplification and gel electrophoresis were used to determine the microbiota. RESULTS: 12 of the OAB patients had DO shown on their urodynamic studies; the remaining 9 patients had a normoactive detrusor on their urodynamic measurements. Overall, there were no substantial differences among the demographic characteristics of the subjects. The samples were classified as the following: 180 phyla, 180 classes, 179 orders, 178 families, 175 genera, and 138 species. The least commonly observed phyla were Proteobacteria, with an average presence of 10%, followed by Bacteroidetes with 15%, Actinobacteria with 16%, and Firmicutes with 41%. Most of the sequences could be classified according to the genus level for each sample. DISCUSSION: Significant differences were observed in the urinary microbiome of patients with overactive bladder syndrome who have detrusor overactivity on urodynamics compared to OAB patients without detrusor overactivity and matched controls. OAB patients with detrusor overactivity have a significantly less diverse microbiome and show a higher proportion of Lactobacillus, particularly Lactobacillus iners. The results imply that the urinary microbiome could be involved in the pathogenesis of a specific phenotype of OAB. The urinary microbiome could be a new starting point to study the causes and treatments of OAB.

Study protocol of a multicentre double-blind RCT, comparing a traditional RCT with an aggregated N-of-1 trial: GAG therapy Efficacy Trial Solution for Bladder pain syndrome/Interstitial cystitis (GETSBI study).

INTRODUCTION: Obtaining level 1 evidence on efficacy of glycosaminoglycan (GAG) therapy is difficult, due to low incidence of bladder pain syndrome/interstitial cystitis (BPS/IC) and heterogeneous symptoms experienced by patients with BPS/IC. Currently, because of a lack of high-grade evidence, the recommendation for applying GAG therapy in most guidelines is 'low grade'. An aggregated N-of-1 trial is a multicrossover design that yields similar level 1 evidence as a traditional randomised controlled trial (RCT), while requiring far less patients. The goal of this study is to investigate the efficacy of intravesical GAG therapy (Ialuril) for patients with BPS/IC with Hunner lesions using a dual RCT and aggregated N-of-1 trial design to obtain level 1 evidence. METHODS AND ANALYSIS: The GETSBI study is a double-blind multidesign multicentre randomised placebo-controlled study to assess the short-term and long-term efficacy of hyaluronic acid (1.6%) + chondroitin sulfate (2%) therapy (Ialuril Prefill, IBSA, Goodlife) in patients with symptomatic BPS/IC with Hunner lesions. It starts as a standard RCT (n=80), but continues as an aggregated N-of-1 trial. There are three parallel arms, receiving blinded treatment for three periods (1 x/week for 6 weeks, ratio placebo to intervention in periods of 2:1). Followed by an open prospective part for the long-term efficacy. The primary study outcome is the maximum bladder pain experienced in the last 3 days measured using the visual analogue pain scale (0-10).This study is a collaboration with the Dutch government and will deliver evidence for the decision to reimburse the therapy. Furthermore, this multidesign study will allow us to compare the two main methods to evaluate applicability for future study designs for BPS/IC research. ETHICS AND DISSEMINATION: Ethical approval was given by METC Oost-Nederland, file number: 2020-7265, NL-number: NL76290.091.20. Findings from this study will be disseminated via publication, reports and conference presentations. TRIAL REGISTRATION NUMBER: ClinicalTrials.gov identifier (NCT number): NCT05518864.

Molecular Processes in Stress Urinary Incontinence: A Systematic Review of Human and Animal Studies.

Stress urinary incontinence (SUI) is a common and burdensome condition. Because of the large knowledge gap around the molecular processes involved in its pathophysiology, the aim of this review was to provide a systematic overview of genetic variants, gene and protein expression changes related to SUI in human and animal studies. On 5 January 2021, a systematic search was performed in Pubmed, Embase, Web of Science, and the Cochrane library. The screening process and quality assessment were performed in duplicate, using predefined inclusion criteria and different quality assessment tools for human and animal studies respectively. The extracted data were grouped in themes per outcome measure, according to their functions in cellular processes, and synthesized in a narrative review. Finally, 107 studies were included, of which 35 used animal models (rats and mice). Resulting from the most examined processes, the evidence suggests that SUI is associated with altered extracellular matrix metabolism, estrogen receptors, oxidative stress, apoptosis, inflammation, neurodegenerative processes, and muscle cell differentiation and contractility. Due to heterogeneity in the studies (e.g., in examined tissues), the precise contribution of the associated genes and proteins in relation to SUI pathophysiology remained unclear. Future research should focus on possible contributors to these alterations.

Catalytic and structural properties of ATP-dependent caprolactamase from Pseudomonas jessenii.

Caprolactamase is the first enzyme in the caprolactam degradation pathway of Pseudomonas jessenii. It is composed of two subunits (CapA and CapB) and sequence-related to other ATP-dependent enzymes involved in lactam hydrolysis, like 5-oxoprolinases and hydantoinases. Low sequence similarity also exists with ATP-dependent acetone- and acetophenone carboxylases. The caprolactamase was produced in Escherichia coli, isolated by His-tag affinity chromatography, and subjected to functional and structural studies. Activity toward caprolactam required ATP and was dependent on the presence of bicarbonate in the assay buffer. The hydrolysis product was identified as 6-aminocaproic acid. Quantum mechanical modeling indicated that the hydrolysis of caprolactam was highly disfavored (ΔG0 '= 23 kJ/mol), which explained the ATP dependence. A crystal structure showed that the enzyme exists as an (αß)2 tetramer and revealed an ATP-binding site in CapA and a Zn-coordinating site in CapB. Mutations in the ATP-binding site of CapA (D11A and D295A) significantly reduced product formation. Mutants with substitutions in the metal binding site of CapB (D41A, H99A, D101A, and H124A) were inactive and less thermostable than the wild-type enzyme. These residues proved to be essential for activity and on basis of the experimental findings we propose possible mechanisms for ATP-dependent lactam hydrolysis.

Urinary Microbiome and its Correlation with Disorders of the Genitourinary System.

PURPOSE: Until recently, the urine of healthy individuals was assumed to be sterile. However, improvement of bacterial detection methods has debunked this assumption. Recent studies have shown that the bladder contains microbiomes, which are not detectable under standard conditions. In this review, we aimed to present an overview of the published literature regarding the relationship between urinary microbiota and functional disorders of the genitourinary system. METHODS: We searched Medline, PubMed, Embase, The Cochrane library and Scopus to identify RCTs published, with MeSH and free keywords including microbiota, bladder pain syndrome, prostatitis, kidney stone disease, and bladder cancer until September 2020. Randomized controlled trials investigating microbiome and lower urinary tract symptoms were included. Non-randomized trials, cross-over trials and pooled studies were excluded. The articles were critically appraised by two reviewers. CONCLUSION: The urine microbiome is a newly introduced concept, which has attracted the attention of medical researchers. Since its recent introduction, researchers have conducted many fruitful studies on this phenomenon, changing our perspective toward the role of bacteria in the urinary tract and our perception of the genitourinary system health. RESULT: A deeper understanding of the urinary microbiome can help us to develop more efficient methods for restoring the microbiota to a healthy composition and providing symptom relief. Modification of the urinary microbiome without antibiotic use can be a possible venue for future research.

ls clinical practice aligned with the latest scientific evidence on GAG therapy?

The role of glycosaminoglycans (GAGs) as key components of the protective bladder barrier is well accepted. Replenishment of the GAG layer could restore the normal protective barrier function of the damaged bladder urothelium and re-establish normal permeability. A number of bladder diseases, including interstitial cystitis/bladder pain syndrome, recurrent urinary tract infections, radiation cystitis, and other forms of cystitis may benefit from GAG therapy.

Mutations in PMR1 stimulate xylose isomerase activity and anaerobic growth on xylose of engineered Saccharomyces cerevisiae by influencing manganese homeostasis.

Combined overexpression of xylulokinase, pentose-phosphate-pathway enzymes and a heterologous xylose isomerase (XI) is required but insufficient for anaerobic growth of Saccharomyces cerevisiae on d-xylose. Single-step Cas9-assisted implementation of these modifications yielded a yeast strain expressing Piromyces XI that showed fast aerobic growth on d-xylose. However, anaerobic growth required a 12-day adaptation period. Xylose-adapted cultures carried mutations in PMR1, encoding a Golgi Ca2+/Mn2+ ATPase. Deleting PMR1 in the parental XI-expressing strain enabled instantaneous anaerobic growth on d-xylose. In pmr1 strains, intracellular Mn2+ concentrations were much higher than in the parental strain. XI activity assays in cell extracts and reconstitution experiments with purified XI apoenzyme showed superior enzyme kinetics with Mn2+ relative to other divalent metal ions. This study indicates engineering of metal homeostasis as a relevant approach for optimization of metabolic pathways involving metal-dependent enzymes. Specifically, it identifies metal interactions of heterologous XIs as an underexplored aspect of engineering xylose metabolism in yeast.

TRPV4 mediates afferent pathways in the urinary bladder. A spinal c-fos study showing TRPV1 related adaptations in the TRPV4 knockout mouse.

The role of transient receptor potential vanilloid subtype 4 (TRPV4) channels in urinary bladder afferent neural pathways was investigated using spinal c-fos measurements in mice. Anesthetized wild type and TRPV4 knockout (-/-) mice underwent noxious bladder distention and treatment with either intravesical instillation with lipopolysaccharide (LPS), or the TRPV1 agonist resiniferatoxin (RTX), vehicle or an intraperitoneal injected TRPV4 antagonist (HC067047). Mice underwent paraformaldehyde perfusion for rapid fixation and L6-S1 spinal cord sections were removed followed by immunohistochemical staining for c-fos. A number of c-fos expressing neurons in the dorsal horns of L6-S1 spinal cord transections were quantified. Groups were compared using univariate ANOVA. Even with the absence of bladder inflammation on H&E, the TRPV4 -/- mice still have a significant twofold higher c-fos expression (n = 39, SD 2) after noxious bladder distention compared to wild type mice (n = 20, SD 3). A twofold increase in c-fos expression was observed after LPS treatment in wild types (n = 42, SD 5), but no increase was seen in TRPV4 -/- mice (n = 42, SD 2). After desensitization of primary afferent C-nerve fibers with RTX, c-fos expression in TRPV4-/- mice decreased significantly (threefold) (n = 12, SD 4). Results imply that TRPV4 channels are important for bladder afferent signaling. TRPV4 -/- mice bladders generate more noxious sensory output, which is predominantly mediated through TRPV1 expressing high threshold nerve fibers. This study reveals TRPV1 related adaptive changes in afferent pathways of the TRPV4 -/- mouse. We propose that this effect is caused by a congenital impairment of low threshold nerves that mediate normal bladder filling sensations.

Enzymatic network for production of ether amines from alcohols.

We constructed an enzymatic network composed of three different enzymes for the synthesis of valuable ether amines. The enzymatic reactions are interconnected to catalyze the oxidation and subsequent transamination of the substrate and to provide cofactor recycling. This allows production of the desired ether amines from the corresponding ether alcohols with inorganic ammonium as the only additional substrate. To examine conversion, individual and overall reaction equilibria were established. Using these data, it was found that the experimentally observed conversions of up to 60% observed for reactions containing 10 mM alcohol and up to 280 mM ammonia corresponded well to predicted conversions. The results indicate that efficient amination can be driven by high concentrations of ammonia and may require improving enzyme robustness for scale-up. Biotechnol. Bioeng. 2016;113: 1853-1861. © 2016 Wiley Periodicals, Inc.

Peptide synthesis in neat organic solvents with novel thermostable proteases.

Biocatalytic peptide synthesis will benefit from enzymes that are active at low water levels in organic solvent compositions that allow good substrate and product solubility. To explore the use of proteases from thermophiles for peptide synthesis under such conditions, putative protease genes of the subtilase class were cloned from Thermus aquaticus and Deinococcus geothermalis and expressed in Escherichia coli. The purified enzymes were highly thermostable and catalyzed efficient peptide bond synthesis at 80°C and 60°C in neat acetonitrile with excellent conversion (>90%). The enzymes tolerated high levels of N,N-dimethylformamide (DMF) as a cosolvent (40-50% v/v), which improved substrate solubility and gave good conversion in 5+3 peptide condensation reactions. The results suggest that proteases from thermophiles can be used for peptide synthesis under harsh reaction conditions.

Metabolism of ß-valine via a CoA-dependent ammonia lyase pathway.

Pseudomonas species strain SBV1 can rapidly grow on medium containing ß-valine as a sole nitrogen source. The tertiary amine feature of ß-valine prevents direct deamination reactions catalyzed by aminotransferases, amino acid dehydrogenases, and amino acid oxidases. However, lyase- or aminomutase-mediated conversions would be possible. To identify enzymes involved in the degradation of ß-valine, a PsSBV1 gene library was prepared and used to complement the ß-valine growth deficiency of a closely related Pseudomonas strain. This resulted in the identification of a gene encoding ß-valinyl-coenzyme A ligase (BvaA) and two genes encoding ß-valinyl-CoA ammonia lyases (BvaB1 and BvaB2). The BvaA protein demonstrated high sequence identity to several known phenylacetate CoA ligases. Purified BvaA enzyme did not convert phenyl acetic acid but was able to activate ß-valine in an adenosine triphosphate (ATP)- and CoA-dependent manner. The substrate range of the enzyme appears to be narrow, converting only ß-valine and to a lesser extent, 3-aminobutyrate and ß-alanine. Characterization of BvaB1 and BvaB2 revealed that both enzymes were able to deaminate ß-valinyl-CoA to produce 3-methylcrotonyl-CoA, a common intermediate in the leucine degradation pathway. Interestingly, BvaB1 and BvaB2 demonstrated no significant sequence identity to known CoA-dependent ammonia lyases, suggesting they belong to a new family of enzymes. BLAST searches revealed that BvaB1 and BvaB2 show high sequence identity to each other and to several enoyl-CoA hydratases, a class of enzymes that catalyze a similar reaction with water instead of amine as the leaving group.

X-ray crystallographic validation of structure predictions used in computational design for protein stabilization.

Protein engineering aimed at enhancing enzyme stability is increasingly supported by computational methods for calculation of mutant folding energies and for the design of disulfide bonds. To examine the accuracy of mutant structure predictions underlying these computational methods, crystal structures of thermostable limonene epoxide hydrolase variants obtained by computational library design were determined. Four different predicted effects indeed contributed to the obtained stabilization: (i) enhanced interactions between a flexible loop close to the N-terminus and the rest of the protein; (ii) improved interactions at the dimer interface; (iii) removal of unsatisfied hydrogen bonding groups; and (iv) introduction of additional positively charged groups at the surface. The structures of an eightfold and an elevenfold mutant showed that most mutations introduced the intended stabilizing interactions, and side-chain conformations were correctly predicted for 72-88% of the point mutations. However, mutations that introduced a disulfide bond in a flexible region had a larger influence on the backbone conformation than predicted. The enzyme active sites were unaltered, in agreement with the observed preservation of catalytic activities. The structures also revealed how a c-Myc tag, which was introduced for facile detection and purification, can reduce access to the active site and thereby lower the catalytic activity. Finally, sequence analysis showed that comprehensive mutant energy calculations discovered stabilizing mutations that are not proposed by the consensus or B-FIT methods.

Stabilization of cyclohexanone monooxygenase by a computationally designed disulfide bond spanning only one residue.

Enzyme stability is an important parameter in biocatalytic applications, and there is a strong need for efficient methods to generate robust enzymes. We investigated whether stabilizing disulfide bonds can be computationally designed based on a model structure. In our approach, unlike in previous disulfide engineering studies, short bonds spanning only a few residues were included. We used cyclohexanone monooxygenase (CHMO), a Baeyer-Villiger monooxygenase (BVMO) from Acinetobacter sp. NCIMB9871 as the target enzyme. This enzyme has been the prototype BVMO for many biocatalytic studies even though it is notoriously labile. After creating a small library of mutant enzymes with introduced cysteine pairs and subsequent screening for improved thermostability, three stabilizing disulfide bonds were identified. The introduced disulfide bonds are all within 12 Å of each other, suggesting this particular region is critical for unfolding. This study shows that stabilizing disulfide bonds do not have to span many residues, as the most stabilizing disulfide bond, L323C-A325C, spans only one residue while it stabilizes the enzyme, as shown by a 6 °C increase in its apparent melting temperature.

Priming ammonia lyases and aminomutases for industrial and therapeutic applications.

Ammonia lyases (AL) and aminomutases (AM) are emerging in green synthetic routes to chiral amines and an AL is being explored as an enzyme therapeutic for treating phenylketonuria and cancer. Although the restricted substrate range of the wild-type enzymes limits their widespread application, the non-reliance on external cofactors and direct functionalization of an olefinic bond make ammonia lyases attractive biocatalysts for use in the synthesis of natural and non-natural amino acids, including ß-amino acids. The approach of combining structure-guided enzyme engineering with efficient mutant library screening has extended the synthetic scope of these enzymes in recent years and has resolved important mechanistic issues for AMs and ALs, including those containing the MIO (4-methylideneimidazole-5-one) internal cofactor.

Purification and use of E. coli peptide deformylase for peptide deprotection in chemoenzymatic peptide synthesis.

Peptide deformylases (PDFs) catalyze the removal of the formyl group from the N-terminal methionine residue in nascent polypeptide chains in prokaryotes. Its deformylation activity makes PDF an attractive candidate for the biocatalytic deprotection of formylated peptides that are used in chemoenzymatic peptide synthesis. For this application it is essential to use PDF preparations that are free of contamination by peptidases that can cleave internal peptide bonds. Therefore, different purification methods were attempted and an industrially applicable purification procedure was developed based on a single anion-exchange chromatography step of an engineered PDF variant that was equipped with an anionic octaglutamate tag. The deformylation activity and stability of the engineered enzyme were similar to those of the wild-type PDF. This purification method furnished a PDF preparation with a 1500-fold decreased level of contamination by amidases and peptidases as compared to cell-free extract. It was shown that the enzyme could be used for deprotection of a formylated dipeptide that was prepared by thermolysin-mediated coupling.

A new, straightforward ex vivo organoid bladder mucosal model for preclinical research.

PURPOSE: We developed an experimental ex vivo organoid bladder mucosal model that can be used for experimental research purposes to create alternatives to current animal models. MATERIALS AND METHODS: We developed an ex vivo organoid bladder mucosal model by immobilizing a type I collagen scaffold on the bottom of a Transwell® insert, creating a 2-compartment system. Mucosal biopsies from porcine bladders were placed on top of the scaffold and cultured in different mediums. We evaluated the morphological aspects of biopsy tissue. Cultured samples were assessed by scanning electron microscopy, and immunohistochemical and histochemical staining for cell identification, proliferation and morphology. RESULTS: Cells remained viable in Dulbecco's modified Eagle's medium/F-12 and smooth muscle cell medium for up to 3 weeks. The mucosa retained normal morphological characteristics for up to 1 week. Cells (mostly urothelial cells) proliferated and fully covered the scaffold surface within 3 weeks. CONCLUSIONS: We developed an experimental ex vivo organoid model of bladder mucosa for preclinical experimental research. This model could be used for high volume screening for pharmacology and toxicology experiments. It has the potential to replace currently used animal models.