Neuroinflammatory gene expression analysis reveals potential novel mediators and treatment targets in interstitial cystitis with Hunner lesions

Potential Role of ABCF2 Gene in Pudendal Nerve Neuropathy and Interstitial Cystitis

BACKGROUND/OBJECTIVES

Symptoms of pudendal nerve neuropathy may overlap with various symptoms of interstitial cystitis (IC). As documented, there is a well-established correlation between the genes involved in ATP metabolism, neuropathy, and IC. ATP-binding cassette (ABC) transporters genes, in fact, are vital for ATP signaling. This study aims to associate the ABCF2 gene with a suspected pudendal nerve neuropathy and IC.

METHODS

Histological analysis was conducted for diagnosing IC while the genetic variant was identified by whole exome sequencing (WES) Trio and confirmed through Sanger.

RESULTS

We report a patient with IC, confirmed by histological examination, presenting with a suspected bladder and pudendal nerve neuropathy, though not analytically confirmed. Histological analysis revealed urothelial detachment caused by a dense subepithelial lymphocytic infiltrate, predominantly composed of mast cells, which serve as key diagnostic markers for interstitial cystitis (IC). WES analysis identified the heterozygous genetic variant c.1253T>G p.Phe418Cys within ABCF2 gene, precisely in its functional domain which actively operates in the hydrolysis of ATP energizing various biological systems. As reported, this gene displays high expression patterns in bladder tissue. The variant, absent in the healthy brother, was inherited from the father which presents mosaicism. The in silico prediction analyses classified this variant as pathogenic, identifying potential alterations in the protein structure.

CONCLUSIONS

Although the precise role of ABCF2 should be supported by further studies, we hypothesize that its disruption might impair ATP metabolism, likely altering the nociceptive response and leading to the patient's neuropathy. Further analyses are imperative to validate this research, for laying the groundwork for a specific therapy targeting the genetic dysregulation involved in this condition.

Transient receptor potential ankyrin 1 channels in the bladder mediate low temperature elicited bladder overactivity in rats

AIMS

This study aimed to investigate whether pathways involving transient receptor potential ankyrin 1 (TRPA1) channels in the urinary bladder mediate the bladder overactivity elicited by exposure to a low temperature in rats.

METHODS

At postnatal week 10, female Sprague-Dawley (SD) rats were intraperitoneally injected with the TRPA1 channel antagonist, HC030031, at room temperature (RT) and subsequently exposed to low temperature (LT). Bladder specimens treated with HC030031 were evaluated for contractions through cumulative addition of the TRPA1 channel agonist trans-cinnamaldehyde. Two days before cystometric investigation, small interfering RNA (siRNA) targeting TRPA1 was transfected into urinary bladders. Then, cystometric investigations were performed on rats subjected to TRPA1 siRNA transfection at both RT and LT. Expression of TRPA1 channels in the urinary bladder was assessed through immunohistochemistry and real-time reverse transcription-polymerase chain reaction.

RESULTS

At RT, micturition patterns were unaffected by HC030031 treatment. However, upon exposure to LT, rats treated with HC030031 exhibited a reduction of LT-elicited bladder overactivity, as evidenced by inhibited decreases in voiding interval, micturition volume, and bladder capacity. Additionally, HC030031 inhibited trans-cinnamaldehyde-induced contractions. Immunohistochemical analysis showed the presence of TRPA1 channels in the urinary bladder. Notably, rats with TRPA1 siRNA-transfected bladders could partially inhibit bladder overactivity during LT exposure.

CONCLUSIONS

These findings indicate that pathways involving TRPA1 channels expressed in the urinary bladder could mediate the LT-elicited bladder overactivity.

A bibliometric analysis of top-cited journal articles in interstitial cystitis and bladder pain syndrome

INTRODUCTION AND HYPOTHESIS

To identify and compare the top-cited articles from all indexed journals and urology-nephrology and obstetrics-gynecology journals in the Institute for Scientific Information Web of Science's Citation Index Expanded on interstitial cystitis and bladder pain syndrome (IC/BPS).

METHODS

Cross-sectional bibliometric analysis of top-cited articles in Web of Science^TM (WoS) from 1900-2022. The articles were retrieved by the MeSH terms from NCBI. The characteristics of top 100 cited articles from all indexed journals and specialized journals were evaluated.

RESULTS

A total of 5547 articles were collected from 1115 journals, in which 3225 articles were from 141 urological and gynecological specialized journals. The USA and the UK were the top two origins for articles on interstitial cystitis. The articles from non-specialized journals were more frequently cited than those from specialized journals (median [IQR], 221.5 [189.8-313.5] vs 131.0 [126.0-142.8], P < 0.0001). The citation number per year showed similar results (median [IQR], 239.9 [194.5-311.8] vs 132.0 [126.7-140.5], P < 0.0001). There were many more open-access articles in non-specialized than specialized journals (P = 0.0018).

CONCLUSIONS

The current study initially queried the articles published on WoS on IC/BPS by the number of citations to identify the differences between two journal categories. The characteristics and trends of research were analyzed by citations to provide insights into the current research status and future direction.

Men With Chronic Orchialgia Exhibit Differential Neuroinflammatory Gene Expression Relative to Asymptomatic Controls

OBJECTIVE

To identify differences in neuroinflammatory gene expression in individuals with chronic orchialgia (CO) compared to asymptomatic controls.

METHODS

Vas deferens, spermatic cord fascia, blood, and urine were collected from 9 men with CO at time of microscopic spermatic cord denervation and 7 asymptomatic controls at time of vasectomy. RNA was isolated and analyzed with the NanoString Human Neuroinflammation panel. Data were normalized, gene expression fold changes and enriched pathways relative to asymptomatic controls were determined. Gene expression was considered significantly different if there was a >2-fold change and P-value <.05 relative to controls.

RESULTS

Mean patient age was 51 years and median symptom duration 12 months. There were 26 genes with significantly differential expression in vas deferens. cFos, a marker of nociceptive pain, had the greatest difference (30.2-fold change, P <.000001). Enriched pathways in vas deferens included nerve function, matrix remodeling, and innate immune responses. In fascia, cFos also had the greatest differential expression (38-fold, P = .000002), followed by S100A12 (11-fold, inducer of innate immune response). Enriched pathways in fascia included nerve function and inflammation. In blood, there were no differentially expressed genes, and in urine there were 95 differentially expressed genes.

CONCLUSION

Men with CO have a diverse set of neuroinflammatory genes with differential expression in tissue and urine relative to healthy controls. These findings confirm pathologic changes in tissue targeted by denervation surgery, and suggest molecular changes in neuropathic pain that could lead to biomarker identification and novel treatment.