Biomarkers predicting the severity of obstruction-induced bladder dysfunction

描述(由申请人提供)： 良性前列腺增生症(BPH)继发的膀胱功能障碍是老年男性的主要病症。BPH可引发与下尿路症状(LUTS)相关的变化。虽然这些症状与前列腺增大的影响有关，但前列腺大小和梗阻膀胱症状的严重程度似乎没有直接关系。因此，尿动力学结果不能准确预测膀胱病理水平，也不能准确预测手术或药物治疗后恢复的可能性。因此，生物标记物可以识别男性梗阻性膀胱功能障碍的严重程度，以及在什么时候功能障碍变得不可逆转，将在这种疾病的治疗中具有重要价值。虽然有相当多的证据表明，部分出口阻塞会导致特定的细胞和亚细胞突起，特别是胆碱能神经传递和线粒体功能的缺血和自由基损伤，但介导这些细胞功能障碍的膜损伤的确切特征尚不清楚，这是我们建议继续研究的基础。我们提出的研究假设是：梗阻性膀胱功能障碍从代偿膀胱功能到不可逆性膀胱失代偿的进展主要由两个过程介导：1)缺血/再灌注引起的细胞和亚细胞损伤，其特征是特定的细胞和亚细胞膜，特别是胆碱能神经、突触和神经元和细胞线粒体的氧化、过氧化和硝化程度逐渐增加；以及2)结缔组织逐渐取代功能性平滑肌。我们建议的具体目标是：1)使用我们的兔部分出口梗阻模型，我们将：a)定量特定细胞和亚细胞膜的ROS和RNS损伤水平；b)定量Sm/C。我们将确定特定膜系统的ROS和RNS损伤水平如何与每个梗阻持续时间的失代偿水平相关；还将确定每个梗阻持续时间每个失代偿水平的Sm/C。要研究的细胞膜和亚细胞膜包括：细胞核、细胞壁、线粒体、肌浆网、神经和突触膜。2)随着梗阻时间的延长，通过切除部分出口梗阻来量化梗阻膀胱的功能(收缩)、结构(SM/C)和生化(ROS和RNS损伤)的恢复程度。在每个时间点，我们将确定逆转时和恢复期结束时的膀胱失代偿程度。通过直接比较逆转时膀胱的结构和生化状态与恢复期结束时的膀胱结构和生化状态，我们可以确定结构和生化恢复的程度；通过将这些数据直接与膀胱的功能恢复(或缺乏恢复)进行比较，我们将能够确定膀胱从梗阻功能障碍中恢复的具体机制；以及膀胱进展到完全失代偿的机制。从这些研究中，我们希望找出梗阻的膀胱的特征，即使在移除梗阻的情况下，也会阻止膀胱恢复。通过这些研究，我们将产生与我们的假设相关的重要新信息。此外，所产生的数据可用于开发用于治疗梗阻性膀胱功能障碍的新型、特异和有效的抗氧化剂产品。 公共卫生相关性： 良性前列腺增生症(BPH)继发的膀胱功能障碍是老年男性的主要病症。我们研究的主要目标是开发生物标志物，既可以预测梗阻性膀胱功能障碍的程度，也可以预测手术或药物干预的结果。我们提出的研究假设是：梗阻性膀胱功能障碍从代偿膀胱功能到不可逆性膀胱失代偿的进展主要由两个过程介导：1)缺血/再灌注引起的细胞和亚细胞损伤，其特征是特定的细胞和亚细胞膜，特别是胆碱能神经、突触和神经元和细胞线粒体的氧化、过氧化和硝化程度逐渐增加；以及2)结缔组织逐渐取代功能性平滑肌。

DESCRIPTION (provided by applicant): Bladder dysfunction secondary to benign prostatic hyperplasia (BPH) is a major affliction of aging men. BPH can initiate changes associated with lower urinary tract symptoms (LUTS). Although these symptoms are related to the effects of an enlarging prostate there appears to be no direct relationship between prostate size and severity of obstructive bladder symptoms. Therefore, urodynamic findings cannot accurately predict either level of bladder pathology, or potential for recovery following surgery or pharmacological therapy. Thus, bio-markers that can identify the severity of male obstructive bladder dysfunction, and at what point the dysfunction becomes irreversible, would be of significant value in the management of the disorder. Although there is considerable evidence that partial outlet obstruction results in both ischemic and free radical damage to specific cellular and subcellular processes, especially cholinergic neurotransmission, and mitochondrial function, the exact characteristics of the membrane damage that mediates these cellular dysfunctions are not known, and are the bases for our proposed continuing studies. The hypothesis for our proposed study is: The progression of obstructive bladder dysfunction from compensated bladder function through irreversible bladder decompensation is mediated primarily by two processes: 1) Cellular and subcellular damage induced by ischemia/reperfusion, which can be characterized by progressively increasing oxidation, peroxidation, and nitration of specific cellular and subcellular membranes, especially those of the cholinergic nerves, synapses, and neuronal and cellular mitochondria, and 2) progressive replacement of functional smooth muscle with connective tissue. The specific aims of our proposal are: 1) Using our rabbit model of partial outlet obstruction, we will: a) quantitate the level of ROS and RNS damage to specific cellular and subcellular membranes; b) quantitate the Sm/C. We will determine how the levels of ROS and RNS damage to specific membrane systems correlate with the level of decompensation at each duration of obstruction; and also determine the Sm/C for each level of decompensation at each duration of obstruction. The cellular and subcellular membranes to be studied include: nuclei, cell wall, mitochondria, sarcoplasmic reticulum, nerve and synaptic membranes. 2) We will quantitate the degree of functional (contractile), structural (SM/C), and biochemical (ROS and RNS damage) recovery of obstructed bladders by removal of the partial outlet obstruction at increasing durations of obstruction. At each time point we will determine the level of bladder decompensation at both the time of reversal, and at the end of the recovery period. By directly comparing the structural and biochemical state of the bladder at the time of reversal with the structural and biochemical state of the bladder at the end of the recovery period we can determine the degree of structural and biochemical recovery; and by directly comparing these data with the functional recovery (or lack of recovery) of the bladder we will be able to identify specific mechanisms by which the bladder recovers from obstructive dysfunction; and the mechanisms involved in the bladder progressing to full decompensation. From these studies we expect to identify the characteristics of obstructed bladders that prevent the bladder from recovering even when the obstruction is removed. Through these studies we will generate significant new information related to our hypothesis. In addition, the data generated can be used to develop novel and specific and effective anti-oxidant products for the treatment of obstructive bladder dysfunction. PUBLIC HEALTH RELEVANCE: Bladder dysfunction secondary to benign prostatic hyperplasia (BPH) is a major affliction of aging men. The major goal of our studies is to develop biomarkers that can predict both the level of obstructive bladder dysfunction, and predict the outcome of either surgical or pharmacological intervention. The hypothesis for our proposed study is: The progression of obstructive bladder dysfunction from compensated bladder function through irreversible bladder decompensation is mediated primarily by two processes: 1) Cellular and subcellular damage induced by ischemia/reperfusion, which can be characterized by progressively increasing oxidation, peroxidation, and nitration of specific cellular and subcellular membranes, especially those of the cholinergic nerves, synapses, and neuronal and cellular mitochondria, and 2) progressive replacement of functional smooth muscle with connective tissue.