Nitric Oxide/cGMP Modulation of Corporal Fibrosis Caused by Neuropraxia

一氧化氮/cGMP 调节神经失用引起的下体纤维化

• 批准号: 7905054
• 负责人: Monica Gabriela Ferrini
• 金额: $ 28.2万
• 依托单位: CHARLES R. DREW UNIVERSITY OF MED & SCI
• 依托单位国家: 美国
• 财政年份: 2008
• 资助国家: 美国
• 起止时间: 2008-08-15 至 2013-07-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7905054
• 关键词: Adverse effects; Affect; Animals; Apoptosis; Axon; Bilateral; Biological Assay; Bladder; Blood; Bromodeoxyuridine; Cell Count; Cell Culture Techniques; Cell Proliferation; Cells; Collagen; Complication; Control Groups; Corpora Cavernosa; Cyclic AMP; Cyclic AMP-Dependent Protein Kinases; Cyclic GMP; Cyclic GMP-Dependent Protein Kinases; Deoxyuridine; Deposition; Development; Erectile dysfunction; Excision; Fibrosis; Functional disorder; GTP-Binding Proteins; Ganglia; Genitourinary system; Goals; Histopathology; Human; Immunohistochemistry; In Vitro; Incubated; Injury; Lead; Los Angeles; Malignant neoplasm of prostate; Measurement; Mediating; Modeling; Molecular; Molsidomine; Mus; Myopathy; Myxoid cyst; Natural regeneration; Nerve; Nerve Crush; Nerve Regeneration; Neurons; Nitrates; Nitric Oxide; Nitric Oxide Donors; Nitrites; Nitroxidergic Nerves; Obstruction; Operative Surgical Procedures; Outcome; Overactive Bladder; Oxidative Stress; PIK3CG gene; Pathway interactions; Pelvis; Pharmaceutical Preparations; Phaseolus vulgaris leucoagglutinin; Physiology; Prevention; Procedures; Process; Production; Proliferating; Protein Kinase A Inhibitor; Proteins; Radical Prostatectomy; Rattus; Reaction; Relative (related person); Reporter Genes; Rodent; Rodent Model; Role; Smooth Muscle; Smooth Muscle Actin Staining Method; Smooth Muscle Myocytes; Soluble Guanylate Cyclase; Techniques; Testing; Tissues; Transforming Growth Factor beta; Transgenic Mice; Veno-occlusive; Western Blotting; analog; axon growth; axon regeneration; improved; inhibitor/antagonist; insight; men; nerve injury; neurogenesis; neurotrophic factor; operation; penis; phosphodiesterase V; prevent; promoter; research study; response; sildenafil; wortmannin

DESCRIPTION (provided by applicant): Erectile dysfunction (ED) is a common complication after radical prostatectomy (RP) for prostate cancer and is due to the injury of the cavernosal nerve during surgery. Despite the improvement of the nerve sparing technique, still many men develop ED after surgery. Until these surgical techniques are perfected to the point where this can be performed without any temporary or permanent injury to the nerves, it seems logical to focus on the prevention of the detrimental and irreversible changes that befall the corporal tissue as a result of the neural injury. We postulate that this process can be studied in rats subjected to bilateral cavernosal nerve resection (BCNR) which is the most severe form of injury that can occur to the nerves, or the bilateral nerve crush model (BCNC) which is a less severe form of neural injury since there is no transection of the axon, and in transgenic mice, to investigate these hypotheses: (1) the corporal fibrosis and smooth muscle cell (SMC) apoptosis induced by BCNR/BCNC can be prevented pharmacologically by the continuous and long-term administration of either PDE5 inhibitors, which increases intracorporeal NO and cGMP. Such treatment leads to a reduction in collagen deposition (decrease in fibrosis) and a positive SM turnover (increase in SMC number) as a result of a reduction in the increased oxidative stress and TGF-beta levels induced by the neural injury. (2) The neural injury induced by BCNR/BCNC may be ameliorated by the modulation of NO/cGMP pathway; through the activation of Pi3K-Akt pathway, inducing neurogenesis, leading to partial axonal regeneration and improvement of the erectile response. To test these hypotheses we propose: Aim 1: To determine the relative effects of modulating the NO and cGMP pathway on corporal collagen and SM turnover rates oxidative stress, neuronal, and smooth muscle apoptosis after BCNR. Aim 2: To determine the mechanism by which NO and/or cGMP preserves the corporal SMC and to ascertain the roles of PKG (protein kinase G) or PKA (protein kinase A) in this process. Aim 3: To determine whether the stimulation of the NO/cGMP pathway induces the release of neurotrophic factors that may lead to regeneration of cavernosal nerves via the Pi3K-AKT pathway. Endpoints: (a) functional determinations of erectile response like electrical field stimulation and cavernosometry; (b) immunohistochemistry for markers of fibrosis, oxidative stress, nitrosative reaction, collagen, SMC turnover, nerve regeneration, and neurotrophic factors; (c) Western blot analysis for some of these markers; (d) assays with selective NO/cGMP modulators in cell culture.

描述（由申请人提供）：勃起功能障碍（艾德）是前列腺癌根治性前列腺切除术（RP）后的常见并发症，是由于手术期间海绵体神经损伤所致。尽管保留神经的技术不断改进，但仍有许多男性在手术后发展为艾德。在这些手术技术完善到可以在不对神经造成任何暂时或永久性损伤的情况下进行手术之前，集中精力预防由于神经损伤而发生的身体组织的有害和不可逆变化似乎是合乎逻辑的。我们假设可以在接受双侧海绵体神经切除术（BCNR）的大鼠中研究这个过程，这是可能发生在神经上的最严重的损伤形式，或者在双侧神经挤压模型（BCNC）中研究这个过程，这是一种不太严重的神经损伤形式，因为没有横断轴突，并且在转基因小鼠中研究这些假设：（1）PDE 5抑制剂可增加BCNR/BCNC诱导的肺纤维化和平滑肌细胞凋亡，并可通过增加NO和cGMP的浓度来预防。由于神经损伤诱导的氧化应激和TGF-β水平的增加减少，这种治疗导致胶原沉积减少（纤维化减少）和正SM转换（SMC数量增加）。(2)BCNR/BCNC诱导的神经损伤可能通过调节NO/cGMP通路，激活Pi 3 K-Akt通路，诱导神经再生，导致部分轴突再生，改善勃起反应而得到改善。 为了验证这些假设，我们提出： 目标1：确定BCNR后调节NO和cGMP通路对胶原和SM周转率、氧化应激、神经元和平滑肌细胞凋亡的相对影响。 目标二：探讨NO和cGMP对平滑肌细胞的保护作用及PKG（Protein Kinase G）和PKA（Protein Kinase A）在这一过程中的作用。 目标3：确定NO/cGMP通路的刺激是否诱导神经营养因子的释放，所述神经营养因子可能通过Pi 3 K-AKT通路导致海绵体神经的再生。 结束点：（a）勃起反应的功能测定，如电场刺激和海绵体测量;（B）纤维化、氧化应激、亚硝化反应、胶原、SMC更新、神经再生和神经营养因子的标志物的免疫组织化学;（c）这些标志物中的一些的蛋白质印迹分析;（d）在细胞培养物中用选择性NO/cGMP调节剂的测定。