Excreção urinária de glicosaminoglicanos em crianças com bexiga neurogênica secundária a mielomeningocele

A excreção urinária de glicosaminoglicanos (GAG) está alterada em várias patologias do trato urinário; o padrão de excreção pode estar associado com o estado da doença. A excreção urinária de GAG em crianças com bexiga neurogênica (BN) secundária a mielomeningocele (MMC) pode também estar alterada, mas até a presente data não há detalhamento epidemiológico dos pacientes e não se correlacionou o padrão de excreção com grau de disfunção vesical. Analisamos a excreção urinária de um grupo bem definido de crianças com MMC e correlacionamos os resultados com escore cistométrico. As amostras de urina de 17 pacientes com MMC, 10 meninos e 7 meninas (média de idade DP de 4,6 2,9 anos) foram obtidas durante o exame cistométrico. As amostras do grupo controle foram obtidas de 18 crianças normais, 13 meninos e 5 meninas (6,9 2,2 anos). Todas as crianças não estavam com infecção urinária, tinham função renal normal e não estavam sob tratamento farmacológico. A quantificação do GAG urinário total foi expressa em μg de ácido hexurônico / mg de creatinina e a proporção dos diferentes tipos de GAGs sulfatados foi obtida por eletroforese em gel de agarose. A avaliação cistométrica foi realizada utilizando aparelho de urodinâmica Dynapack modelo MPX816 (Dynamed, São Paulo, Brasil), a partir da qual o escore cistométrico foi calculado de acordo com procedimento recente publicado. [14]. Não observamos diferença significativa na excreção urinária de GAG total entre meninos e meninas tanto no grupo com MMC ( 0,913 0,528 vs 0,867 0,434, p>0,05) como no grupo controle (0,546 0,240 vs 0,699 0,296, p>0,05). Os resultados mostraram também que a excreção de GAG urinário não se correlacionou com a idade tanto no grupo com MMC ( r = -0,28, p> 0,05) como no grupo controle (r = -0,40, p> 0,05). Entretanto, a comparação dos dois grupos mostrou que o grupo com MMC excretava 52% a mais de GAG total que o grupo controle (0,894 0,477 vs 0,588 0,257, p <0,04). Nesses pacientes a excreção de GAG total não se correlacionou com a complacência vesical isoladamente (r = -0,18, p> 0,05) mas foi significativa e negativamente correlacionada ao escore cistométrico (r= -0,56, p<0,05). Em média, os pacientes com piores escores (<9) excretaram 81% a mais de GAG que os pacientes com melhor escore (>9) (1,157 0,467 vs 0,639 0,133, p<0,04). O sulfato de condroitin foi o GAG sulfatado predominante nos grupos neurogênico e controles (92,5 7,6% vs 96,4 4,8%, respectivamente, p> 0,05), enquanto o sulfato do heparan estava presente em quantidades marcadamente menores; o dermatam sulfato não foi detectado. A excreção urinária de GAG em pacientes com MMC é significativamente maior que a excreção das crianças normais e os altos valores encontrados estão correlacionados a um maior compromentimento da função vesical. Evidências em modelos animais com MMC induzida sugerem que alterações no detrusor estão associadas a um elevado turnover da matriz extra celular (MEC) vesical, o que pode explicar a elevada excreção de GAG nos pacientes com MMC. Além disso, esses resultados indicam que a excreção urinária de GAG pode ser usada como fator adjuvante para a caracterização da disfunção vesical em pacientes com MMC.

Non-invasive antidromic neurostimulation:A simple effective method for improving bladder storage

Patients with intractably diminished bladder storage function are encountered frequently by neurourologists, occasionally requiring reconstructive surgery for appropriate resolution. Although sacral neuromodulation is a recognized effective therapeutic modality, present techniques are technically demanding, invasive, and expensive. This study investigated the effect of non-invasive third sacral nerve (S3) stimulation on bladder activity during filling cystometry. One hundred forty-six patients underwent standard urodynamic filling cystometry that was then immediately repeated. Patients in the study group (n = 74) received antidromic transcutaneous sacral neurostimulation during the second fill and the control group (n = 72) underwent a second fill without neurostimulation. A statistically significant increase in bladder storage capacity without a corresponding rise in detrusor pressure was observed in the neurostimulated patients. This improvement in functional capacity is an encouraging finding that further supports the use of this non-invasive treatment modality in clinical practice. Neurourol. Urodynam. 20:73-84. 2001. (C) 2001 Wiley-Liss, Inc.

Development of a rabbit's urethral sphincter deficiency animal model for anatomical-functional evaluation

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Urodinâmica convencional versus cistometria simplificada para caracterização da incontinência urinária feminina

OBJETIVO: avaliar a concordância dos diferentes parâmetros urodinâmicos comparados à cistometria simplificada, permitindo uma diminuição na relação custo-benefício no diagnóstico da incontinência urinária de esforço (IUE) na mulher. MÉTODOS: foram coletadas e avaliadas retrospectivamente as informações contidas dos prontuários de trinta pacientes acompanhadas, no período de janeiro de 2000 a março de 2001. Todas foram submetidas a exame físico geral e ginecológico. O estudo urodinâmico foi realizado pela técnica convencional, utilizando-se aparelho Dynograph Recorder R-611. A cistometria simplificada foi realizada com auxílio de um equipo em Y de PVC (pressão venosa central), conectado a um sonda de Foley 14 F, que permitia tanto a infusão de soro fisiológico como a captação da pressão intra-vesical. Foram analisados os parâmetros: volume residual, capacidade vesical, complacência, presença de contrações involuntárias do detrusor e perdas urinárias aos esforços. Para determinação da proporção de concordância entre os métodos foram utilizados o teste de concordância de Pearson e o teste de Wilcoxon, para amostras relacionadas. RESULTADOS: a média de idade foi de 50 anos, com extremos variando de 28 a 70 anos. O índice de concordância entre os estudos, na demonstração das perdas urinárias aos esforços, foi de 67%. Para a detecção das contrações involuntárias do detrusor, a proporção de concordância foi de 90%. A média do volume residual encontrado na cistometria simplificada foi de 16,8 ml contra 2 ml da urodinâmica convencional, com diferença significativa (p < 0,01). A média de capacidade vesical máxima no estudo urodinâmico foi de 440,5 ml, enquanto que, na cistometria simplificada, foi de 387 ml (p < 0,05). A complacência vesical foi, em média, significativamente maior na cistometria simplificada (43,0 ml/cmH2O) quando comparada ao estudo urodinâmico (31,5 ml/cmH2O), com p < 0,01. CONCLUSÃO: Avaliações preliminares sugerem que a propedêutica uroginecológica associada à cistometria simplificada é uma opção a ser considerada na avaliação clínica e pré-operatória de pacientes com IUE em substituição à urodinâmica convencional, particularmente onde esta última não se encontra disponível. A cistometria simplificada é um exame acessível que é capaz de detectar contrações involuntárias do detrusor, assim como identificar perdas urinárias com relativa sensibilidade, proporcionando ao examinador noções fidedignas do comportamento vesical.

Role of PKC and CaV1.2 in Detrusor Overactivity in a Model of Obesity Associated with Insulin Resistance in Mice

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

The renin-angiotensin system plays a major role in voiding dysfunction of ovariectomized rats

Aims: The renin-angiotensin system (RAS) plays a major role in cardiovascular diseases in postmenopausal women, but little is known about its importance to lower urinary tract symptoms. In this study we have used the model of ovariectomized (OVX) estrogen-deficient rats to investigate the role of RAS in functional and molecular alterations in the urethra and bladder. Main methods: Responses to contractile and relaxant agents in isolated urethra and bladder, as well as cystometry were evaluated in 4-month OVX Sprague-Dawley rats. Angiotensin-converting enzyme activity and Western blotting for AT1/AT2 receptors were examined. Key findings: Cystometric evaluations in OVX rats showed increases in basal pressure, capacity and micturition frequency, as well as decreased voiding pressure. Angiotensin II and phenylephrine produced greater urethral contractions in OVX compared with Sham group. Carbachol-induced bladder contractions were significantly reduced in OVX group. Relaxations of urethra and bladder to sodium nitroprusside and BAY 41-2272 were unaffected by OVX. Angiotensin-converting enzyme activity was 2.6-fold greater (p < 0.05) in urethral tissue of OVX group, whereas enzyme activity in plasma and bladder remained unchanged. Expressions of AT1 and AT2 receptors in the urethra were markedly higher in OVX group. In bladder, AT1 receptors were not detected, whereas AT2 receptor expression was unchanged between groups. 17β-Estradiol replacement (0.1 mg/kg, weekly) or losartan (30 mg/kg/day) largely attenuated most of the alterations seen in OVX group. Significance: Prolonged estrogen deprivation leads to voiding dysfunction and urethral hypercontractility that are associated with increased ACE activity and up-regulation of angiotensin AT1/AT2 receptor in the urethral tissue. © 2013 Elsevier Inc. All rights reserved.

The renin–angiotensin system plays a major role in voiding dysfunction of ovariectomized rats

Aims: The renin–angiotensin system (RAS) plays a major role in cardiovascular diseases in postmenopausal women, but little is known about its importance to lower urinary tract symptoms. In this study we have used the model of ovariectomized (OVX) estrogen-deficient rats to investigate the role of RAS in functional and molecular alterations in the urethra and bladder. Main methods: Responses to contractile and relaxant agents in isolated urethra and bladder, as well as cystometry were evaluated in 4-month OVX Sprague–Dawley rats. Angiotensin-converting enzyme activity and Western blotting for AT1/AT2 receptors were examined. Key findings: Cystometric evaluations in OVX rats showed increases in basal pressure, capacity and micturition frequency, as well as decreased voiding pressure. Angiotensin II and phenylephrine produced greater urethral contractions in OVX compared with Sham group. Carbachol-induced bladder contractions were significantly reduced in OVX group. Relaxations of urethra and bladder to sodium nitroprusside and BAY 41-2272 were unaffected by OVX. Angiotensin-converting enzyme activity was 2.6-fold greater (p < 0.05) in urethral tissue of OVX group,whereas enzyme activity in plasma and bladder remained unchanged. Expressions of AT1 and AT2 receptors in the urethra were markedly higher in OVX group. In bladder, AT1 receptors were not detected, whereas AT2 receptor expression was unchanged between groups. 17β-Estradiol replacement (0.1 mg/kg, weekly) or losartan (30 mg/kg/day) largely attenuated most of the alterations seen in OVX group. Significance: Prolonged estrogen deprivation leads to voiding dysfunction and urethral hypercontractility that are associated with increased ACE activity and up-regulation of angiotensin AT1/AT2 receptor in the urethral tissue.

The role of inflammatory mediators in the overactive and bladder pain syndromes

The Overactive Bladder (OAB) and Bladder Pain Syndrome (BPS) are debilitating disorders for which the pathophysiological mechanisms are poorly understood. Injury or dysfunction of the protective urothelial barrier layer, specifically the proteoglycan composition and number, has been proposed as the primary pathological characteristic of BPS. For OAB, the myogenic theory with dysfunction of the muscarinic receptors is the most reiterated hypothesis. For both over activity of the inflammatory response has been posited to play a major role in these diseases. We hypothesise that BPS and OAB are peripheral sensory disorders, with an increase in inflammatory mediators, such as cytokines and chemokines, which are capable of activating, either directly or indirectly, sensory nerve activity causing the disease. The aim of the PhD is to identify potential new therapeutic targets for the treatment of BPS and OAB. We used medium throughput quantitative gene expression analysis of 96 inflammation associated mediators to measure gene expression levels in BPS and OAB bladder biopsies and compared them to control samples. Then we created a novel animal model of disease by specific proteoglycan deglycosylation of the bladder mucosal barrier, using the bacterial enzymes Chondroitinase ABC and Heparanase III. These enzymes specifically remove the glycosaminoglycan side chains from the urothelial proteoglycan molecules. We tested role of the identified mediators in this animal model. In addition, in order to determine on which patients peripheral treatment strategies may work, we assessed the effect of local anaesthetics on patients with bladder pain. Gene expression analysis did not reveal a difference in inflammatory genes in the OAB versus control biopsies. However, several genes were upregulated in BPS versus control samples, from which two genes, FGF7 and CLL21 were correlated with patient clinical phenotypes for ICS/PI symptom and problem indices respectively. In order to determine which patients are likely to respond to treatment, we sought to characterise the bladder pain in BPS patients. Using urodynamics and local anaesthetics, we differentiated patients with peripherally mediated pain and patients with central sensitisation of their pain. Finally to determine the role of these mediators in bladder pain, we created an animal model of disease, which specifically replicates the human pathology: namely disruption in the barrier proteoglycan molecules. CCL21 led to an increase in painrelated behaviour, while FGF7 attenuated this behaviour, as measured by cystometry, spinal c-fos expression and mechanical withdrawal threshold examination. In conclusion, we have identified CCL21 and FGF7 as potential targets for the treatment of BPS. Manipulation of these ligands or their receptors may prove to be valuable previously unexploited targets for the treatment of BPS.