Swimming: effects on stress urinary incontinence and the expression of nerve growth factor in rats following transabdominal urethrolysis

Comparative study of two different rat models of stress urinary incontinence

INTRODUCTION AND HYPOTHESIS

The purpose of this study was to compare the success rate and urodynamic characteristics of the rat model of stress Urinary incontinence established by ovariectomy at different times after vaginal dilation.

METHODS

Eighty female rats were randomly divided into three groups: the control group (n = 20), model group A (n = 30), i.e., the animals received colpectasis and bilateral oophorectomy within 1 day; model group B (n = 30), i.e., the animals received bilateral oophorectomy 1 week after colpectasis. The sneeze test and urodynamics were tested.

RESULTS

There was no significant difference between the model group A and the model group B (p > 0.05) in the sneeze test. The leak point pressure (LPP) of model groups A and B was lower than that of the control group (p < 0.05). The LPP value of model group A was lower than that of model group B (p < 0.05). There was no significant difference in maximum bladder capacity (MBC) between model group A and the control group (p > 0.05); the MBC value of model group B was lower than that of the control group and model group A (p < 0.05).

CONCLUSIONS

Models of stress urinary incontinence in rats can be successfully established by both modeling methods. In terms of LPP, model groups A and B had lower values than the control group, and model group A had lower values than model group B. In terms of MBC, there was no difference between model group A and the control group, and model group B had lower values than the control group and model group A.

The Role of the Periaqueductal Gray Matter in Lower Urinary Tract Function

The periaqueductal gray matter (PAG), as one of the mostly preserved evolutionary components of the brain, is an axial structure modulating various important functions of the organism, including autonomic, behavioral, pain, and micturition control. It has a critical role in urinary bladder physiology, with respect to storage and voiding of urine. The PAG has a columnar composition and has extensive connections with its cranially and caudally located components of the central nervous system (CNS). The PAG serves as the control tower of the detrusor and sphincter contractions. It serves as a bridge between the evolutionary higher decision-making brain centers and the lower centers responsible for reflexive micturition. Glutamatergic cells are the main operational neurons in the vlPAG, responsible for the reception and relay of the signals emerging from the bladder, to related brain centers. Functional imaging studies made it possible to clarify the activity of the PAG in voiding and filling phases of micturition, and its connections with various brain centers in living humans. The PAG may be affected in a wide spectrum of disorders, including multiple sclerosis (MS), migraine, stroke, Wernicke’s encephalopathy, and idiopathic normal pressure hydrocephalus, all of which may have voiding dysfunction or incontinence, in certain stages of the disease. This emphasizes the importance of this structure for the basic understanding of voiding and storage disorders and makes it a potential candidate for diagnostic and therapeutic interventions.

Urinary Nerve Growth Factor as a Potential Biomarker of Treatment Outcomes in Overactive Bladder Patients

Purpose

The aim of this study was to investigate urinary nerve growth factor (NGF) as a biomarker of treatment efficacy and recurrence in overactive bladder (OAB) patients.

Methods

We enrolled 189 OAB subjects who visited our outpatient clinic from February 2010 to February 2015. All subjects with OAB received antimuscarinic treatment. A 3-day voiding diary and questionnaire were collected from each patient. Urinary levels of NGF were evaluated at baseline, the beginning of antimuscarinic treatment, and the end of antimuscarinic treatment. Urinary NGF was normalized to urine creatinine (Cr). Between-group comparisons of baseline characteristics were made using the Mann-Whitney U-test. Multivariate logistic regression analyses were used to predict responses to anticholinergic treatment and recurrence. The Wilcoxon signed-rank test with the Bonferroni correction was used for intragroup comparisons. A receiver operating characteristic curve was used to analyze the utility of this biomarker.

Results

Urinary levels of NGF/Cr tended to decrease in patients who responded to treatment (n=62), but this was not significant (P=0.260). Urinary NGF levels were higher at baseline in patients who did not experience recurrence than in those who did (P=0.047). In those who did not experience recurrence (n=29), urinary NGF/Cr decreased at the end of treatment compared to baseline, and this reduction was maintained at 12 weeks after the end of treatment (P<0.05).

Conclusions

Urinary NGF is a potential biomarker for predicting the outcome of antimuscarinic treatment in OAB patients. This may provide useful information when deciding to stop antimuscarinic treatment in responders.

Aerobic exercise affects myostatin expression in aged rat skeletal muscles: a possibility of antiaging effects of aerobic exercise related with pelvic floor muscle and urethral rhabdosphincter

PURPOSE

Aging-induced loss of muscle mass and subsequent reduction of strength is a fundamental cause of frailty, functional decline, and disability. And this may lead to muscular dysfunction, voiding dysfunction, or urinary incontinence due to pelvic muscle weakness induced by aging. Physical exercise has been recommended for the prevention and the treatment of these age-related frail states. We investigated the effects of treadmill exercise on muscle strength, myostatin mRNA and protein expression, and gastrocnemius myocytes proliferation in aged rats to investigate the possible antiaging effects of aerobic exercise on skeletal muscles such as pelvic floor muscles and urethral rhabdosphincter muscle.

METHODS

In this study, 5-month-old male Sprague-Dawley rats were used as the young-age group (n=20) and 24-month-old rats were used as the old-age group (n=20). Each group was randomly divided into two groups (n=10 in each group): the sedentary and the treadmill exercise group. The rats in the exercise groups were forced to run on a motorized treadmill for 30 minutes, once a day, for 6 weeks. For this study, a weight load test, hematoxylin and eosin staining, real-time and reverse transcription polymerase chain reaction for myostatin mRNA, myostatin western blot, and 5-bromo-2'-deoxyuridine immunohistochemistry were performed in the gastrocnemius muscle.

RESULTS

The age-induced reduction of muscle mass and strength was associated with a decrease in myocyte proliferation and an increase in myostatin mRNA and protein expression in the gastrocnemius. However, treadmill exercise improved muscle mass and strength through suppression of myostatin mRNA and protein expression, and myocyte proliferation increase in the gastrocnemius against the aging process.

CONCLUSIONS

Aerobic exercise is a useful strategy for enhancing muscle function against aging-induced loss of skeletal muscle mass and functions.

Oral mucosa stem cells alleviates spinal cord injury-induced neurogenic bladder symptoms in rats

Background

Spinal cord injury (SCI) deteriorates various physical functions, in particular, bladder problems occur as a result of damage to the spinal cord. Stem cell therapy for SCI has been focused as the new strategy to treat the injuries and to restore the lost functions. The oral mucosa cells are considered as the stem cells-like progenitor cells. In the present study, we investigated the effects of oral mucosa stem cells on the SCI-induced neurogenic bladder in relation with apoptotic neuronal cell death and cell proliferation.

Results

The contraction pressure and the contraction time in the urinary bladder were increased after induction of SCI, in contrast, transplantation of the oral mucosa stem cells decreased the contraction pressure and the contraction time in the SCI-induced rats. Induction of SCI initiated apoptosis in the spinal cord tissues, whereas treatment with the oral mucosa stem cells suppressed the SCI-induced apoptosis. Disrupted spinal cord by SCI was improved by transplantation of the oral mucosa stem cells, and new tissues were increased around the damaged tissues. In addition, transplantation of the oral mucosa stem cells suppressed SCI-induced neuronal activation in the voiding centers.

Conclusions

Transplantation of oral mucosa stem cells ameliorates the SCI-induced neurogenic bladder symptoms by inhibiting apoptosis and by enhancing cell proliferation. As the results, SCI-induced neuronal activation in the neuronal voiding centers was suppressed, showing the normalization of voiding function.

An animal study to compare the degree of the suppressive effects on the afferent pathways of micturition between tamsulosin and sildenafil

Background

Tamsulosin, an α1-adrenoceptor antagonist, and sildenafil, a phosphodiesterase (PDE) inhibitor, are reported to improve lower urinary tract symptoms including overactive bladder (OAB). This study is aimed at investing the effects of tamsulosin and sildenafil and comparing the degree of the suppressive effects on the afferent pathways of micturition between them using an animal model of OAB, the spontaneously hypertensive rat (SHR).

Results

The cystometric parameters, the basal pressure and duration of bladder contraction, were significantly increased in the SHR group as compared with the Wistar-Kyoto (WKY) group. The intercontraction interval also significantly decreased in the SHR group. In the SHR-Tam 0.01 mg/kg group and the SHR-Sil 1 mg/kg group, however, the basal pressure and duration were significantly reduced and the intercontraction interval was significantly prolonged. Moreover, the degree of the expression of c-Fos and NGF was significantly higher in the SHR group as compared with the WKY group. But it was significantly reduced in the SHR-Tam 0.01 mg/kg group and the SHR-Sil 1 mg/kg group. Furthermore, tamsulosin had a higher degree of effect as compared with sildenafil.

Conclusions

In conclusion, α1-adrenergic receptor antagonists and PDE-5 inhibitors may have an effect in improving the voiding functions through an inhibition of the neuronal activity in the afferent pathways of micturition.

Effect of Long-term Exercise on Voiding Functions in Obese Elderly Women

Purpose

An overactive bladder (OAB) may be defined as urgency that is a sudden, compelling, difficult to defer desire to pass urine that is usually accompanied by frequency and nocturia and possibly by incontinence. Obesity and old age are two factors in various causes of OAB. Several epidemiologic studies have identified positive associations among obesity, old age, urinary incontinence, and OAB. However, although exercise has been known to improve obesity and reduce incontinent urine loss, little research has been done in elderly women. Therefore, we investigated the effects of exercise on obesity-related metabolic factors, blood lipid factors, and OAB symptoms in elderly Korean women.

Methods

Twenty-one women aged between 69 and 72 years were recruited from the Seoul senior towers in Korea. All subjects worked out on a motorized treadmill and stationary cycle for 40 minutes, respectively, and performed resistance exercise for 30 minutes once a day for 52 weeks. Body composition, blood pressure, blood lipids, OAB symptom score, and King's health questionnaire were investigated and analyzed.

Results

Before performing physical exercise, all subjects showed increased OAB symptoms in association with enhanced body mass index (BMI), percentage fat, and blood lipid profiles. However, physical exercise for 52 weeks suppressed BMI, percentage fat, and blood lipid profiles and thus improved OAB symptoms.

Conclusions

We suggest that long-term physical exercise can be a valuable tool for remarkable improvement of OAB.