Time-dependent changes in bladder function and plantar sensitivity in a rat model of fibromyalgia syndrome induced by hydrochloric acid injection into the gluteus

Early Sacral Neuromodulation Prevented Detrusor Overactivity in Rats With Spinal Cord Injury

OBJECTIVES

Sacral neuromodulation (SNM) has been shown to alleviate bladder dysfunction in patients with overactive bladder and nonobstructive urinary retention. However, the therapeutic effect and mechanism of SNM in neurogenic bladder dysfunction are still not fully understood. Using a rat model of spinal cord injury (SCI), this study aims to investigate the therapeutic effect of early SNM in the bladder-areflexia phase on neurogenic bladder dysfunction and evaluate its possible mechanism.

MATERIALS AND METHODS

Basic physiological parameters such as body/bladder weight, blood pressure, and electrocardiogram results were measured to evaluate the safety of SNM. Enzyme-linked immunosorbent assays and quantitative real-time polymerase chain reaction were used to examine the expression of proinflammatory factors. Hematoxylin and eosin and Masson's trichrome staining were used to observe morphological changes, and cystometry was used to evaluate urodynamic changes after SNM treatment. Western blotting and immunofluorescence staining were used to measure the levels of transient receptor potential vanilloid 1 (TRPV1) and calcitonin gene-related peptide (CGRP) in the L6-S1 dorsal root ganglia (DRGs) and bladder. Capsaicin desensitization was used to investigate whether inhibiting TRPV1 could prevent detrusor overactivity in SCI rats.

RESULTS

Early SNM did not affect the body/bladder weight, heart rate, blood pressure, or the expression of proinflammatory cytokines (PGE2, IL-1, IL-2, IL-6, TGF-β, or TNF-α) in the bladders of SCI rats. Morphologically, early SNM prevented urothelial edema (p = 0.0248) but did not influence collagen/smooth muscle in the bladder. Compared with untreated rats with SCI, the rats treated with SNM exhibited increased bladder capacity (p = 0.0132) and voiding efficiency (p = 0.0179), and decreased nonvoiding contraction (NVC) frequency (p = 0.0240). The maximum pressure, basal pressure, postvoid residual, and NVC amplitude did not change significantly. After the SNM treatment, the expression of TRPV1 in the bladder and CGRP in L6-S1 DRGs weredecreased (L6, p = 0.0160; S1, p = 0.0024) in SCI rats. In capsaicin-desensitized SCI rats, urodynamic results showed an increase in bladder capacity (p = 0.0116) and voiding efficiency (p = 0.0048), and diminished NVC frequency (p = 0.0116), while other parameters did not change significantly.

CONCLUSIONS

Early SNM prevented urothelial edema morphologically and detrusor overactivity in SCI rats. Inhibition of TRPV1 in the bladder and DRGs may be one of the potential mechanisms for preventing detrusor overactivity by SNM.

Excessive exercise induces cardiac arrhythmia in a young fibromyalgia mouse model

Background

Fibromyalgia patients experience cardiovascular complications in addition to musculoskeletal pain. This study aimed to investigate the cardiac effects of a prolonged shallow water gait in a fibromyalgia-induced young mouse model.

Methods

To produce a fibromyalgia mouse model, wild-type mice were administered an intraperitoneal injection of reserpine once a day for three days, and two primary experiments were performed. First, three types of gait tests were performed before and after the reserpine injections as follows: (i) 5 minutes of free gait outside the water, (ii) 1 minute of free gait in shallow warm water, and (iii) 5 minutes of free gait in shallow warm water. Second, electrocardiogram recordings were taken before and after the three gait tests. The average heart rate and heart rate irregularity scores were analyzed.

Results

Exercise-induced cardiac arrhythmia was observed at 1-minute gait in shallow water during the acute stage of induced FM in young mice. Further, both cardiac arrhythmia and a decrease in HR have occurred at 5-minute gait in shallow water at the same mice. However, this phenomenon was not observed in the wild-type mice under any test conditions.

Conclusion

Although a short-term free gait in shallow warm water may be advantageous for increasing the motor activity of FM-model mice, we should be aware of the risk of prolonged and excessive exercise-induced cardiac arrhythmia. For gait exercises in shallow water as a treatment in FM patients. We suggest a gradual increase in exercise duration may be warranted.

The Fibromyalgia Bladder Index in 100 consecutive women with fibromyalgia

INTRODUCTION AND HYPOTHESIS

The Fibromyalgia Bladder Index (FBI) is a validated instrument to quantify bothersome bladder symptoms specifically in women with fibromyalgia syndrome (FMS). The FBI includes two sub-scales: one addressing urinary urgency and bladder pain (UP), the other addressing urinary frequency and nocturia (FN). The objectives of this study are to evaluate the FBI in a cohort of patients with FMS, to correlate it with certain characteristics in this cohort, and to compare it with controls.

METHODS

We performed a case-control study of 100 women with FMS and 155 controls. Demographic data, comorbidities, and other characteristics were registered. Comparison between FBI scores of participants with and without FMS, as well as correlation of FBI scores with the characteristics of FMS patients, were undertaken using independent two-sample t test for continuous outcomes and Pearson's Chi-squared test for categorical outcomes.

RESULTS

The mean UP subscale score of the FBI was significantly higher in the FMS group (10.29 ± 5.61) compared with the controls (1.65 ± 2.65; (p = 0.001). The mean FN subscale score was significantly higher in the FMS group (9.93 ± 5.37) compared with the controls (2.95 ± 3.27; p = 0.001). FMS patients diagnosed >3 years ago had a higher UP subscale score and a higher FN subscale score compared with FMS patients diagnosed <3 years ago (p = 0.020 and p = 0.024 respectively). Menopause and parity significantly increased the FBI scores. Smoking and a history of depression did not significantly affect any of the FBI subscale scores in the FMS group.

CONCLUSION

Women with FMS suffer from bothersome bladder symptoms that can be readily identified and quantified.

Depressive-like symptoms in a reserpine-induced model of fibromyalgia in rats

Since the pathogenesis of fibromyalgia is unknown, treatment options are limited, ineffective and in fact based on symptom relief. A recently proposed rat model of fibromyalgia is based on central depletion of monamines caused by reserpine administration. This model showed widespread musculoskeletal pain and depressive-like symptoms, but the methodology used to measure such symptoms has been criticized. Evidence relates the high prevalence of pain and depression in fibromyalgia to common pathogenic pathways, most probably focused on the monoaminergic system. The present study aims at a validation of the reserpine model of fibromyalgia. For this purpose, rats undergoing this model have been tested for depressive-like symptoms with a Novelty-Suppressed Feeding Test adaptation. Animals administered with reserpine and subjected to forced food deprivation performed a smaller number of incursions to the center of the open field, evidenced by a decrease in the per-minute rate of the rats' approaching, smelling or touching the food. They also took more time to eat from the central food than control rats. These NSFT findings suggest the presence of depressive-like disorders in this animal model of fibromyalgia.

Validation of a culturally compliant voiding platform for urodynamics in African vesicovaginal fistula patients

INTRODUCTION AND HYPOTHESIS

Most patients in regions where obstetric vesicovaginal fistulas (VVF) are endemic void using a squatting posture. Additionally, many patients continue to have lower urinary tract symptoms (LUTS) following fistula closure. We designed and validated a prototype platform that allows urodynamic studies to be performed in a squatting position and conducted a pilot study to assess uroflowmetry in this patient population.

METHODS

Sixteen patients with persistent LUTS following fistula surgery were recruited. Posture measurements were taken in each patient's natural voiding posture on the ground and were then repeated using the platform. Nine patients with persistent urinary incontinence also underwent uroflowmetry. The data were compared with normal values in different nomograms. Paired t tests were used to determine significant differences in posture. One-way ANOVA was used to determine statistical significance between flow rate values.

RESULTS

Only the heel-to-heel distance (H-H) measure of posture was significantly increased on the platform compared with on the ground. The mean corrected Qmax was 0.89 ± 0.46. Flow rate values were significantly lower than mean normal flow rates obtained from the nomograms. In general, the patients' uroflowmetry patterns were similar to those indicative of impaired detrusor function.

CONCLUSION

A platform for conducting urodynamic studies in a squatting posture was successfully validated in the VVF patient population. The finding of increased H-H on the platform is expected, since the patient must accommodate a large funnel for urine collection. The pilot data suggest that patients with persistent urinary incontinence following VVF closure may also have significant voiding dysfunction.