Roles of Nitric Oxide and Superoxide in Cystitis

一氧化氮和超氧化物在膀胱炎中的作用

• 批准号: 9043860
• 负责人: Anthony John Kanai
• 金额: $ 33.55万
• 依托单位: UNIVERSITY OF PITTSBURGH AT PITTSBURGH
• 依托单位国家: 美国
• 财政年份: 2005
• 资助国家: 美国
• 起止时间: 2005-08-01 至 2018-03-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9043860
• 关键词: ANK1 gene; Accounting; Acute; Aftercare; American Cancer Society; Antibodies; Apoptosis; Binding; Bladder; Brain-Derived Neurotrophic Factor; Catheterization; Cells; Chronic; Chronic Phase; Coagulation Process; Collagen; Colon; Cystitis; Deposition; Descending colon; Development; Diagnosis; Dose; Dyes; Dysuria; Electrocoagulation; Fatty Acids; Free Radical Scavengers; Frequencies; Grant; Growth; Health; Hematuria; High Pressure Liquid Chromatography; Hyperbaric Oxygenation; Image; Incontinence; Inflammation; Intracolonic; Ion Channel; Irrigation; Ischemia; Knockout Mice; Label; Lasers; Legal patent; Life; Malignant Neoplasms; Maps; Methods; Mitochondria; Mus; Muscarinic Antagonists; Nerve; Nerve Growth Factors; Neurons; New Agents; Nitric Oxide; Nitric Oxide Synthase; Nitrites; Optics; Organ; Pelvis; Pentosan Polysulfate; Permeability; Peroxonitrite; Phase; Prevalence; Prevention; Radiation; Radiation therapy; Radioprotection; Respiration; Role; Rupture; Secondary to; Spinal Cord; Spinal Ganglia; Staining method; Stains; Suid Herpesvirus 1; Superoxides; Surgical incisions; Swelling; TRPV1 gene; Testing; Therapeutic; Therapeutic Agents; Tissues; United States; Urethra; Urinary Retention; Urothelial Cell; Urothelium; Vanilloid; Vascular Endothelial Cell; Woman; acute symptom; afferent nerve; cell injury; cytochrome c; cytochrome c oxidase; irradiation; men; microsensor; mouse model; novel therapeutics; prevent; receptor; tumor; voltage

DESCRIPTION (provided by applicant): Pelvic organ tumors in men and women are estimated to account for 48% and 21%, respectively, of new tumors diagnosed in the United States in 2012 according to the American Cancer Society (Cancer Facts & Figures, 2012). While irradiation is a key therapy for treating these malignancies, the dose is limited by the potential for developing radiation cystitis. The acute phase of cystitis includes inflammation and bladder overactivity resulting from disruption of the urothelial cell (UC) permeability barrier and sensitization of afferent nerves. A chronic phase can develop in 6-12 months with vascular endothelial cell damage, ischemia, collagen deposition and decreased bladder compliance. During the first grant period, we used nitric oxide (NO•), nitrite (NO2-) and peroxynitrite (ONO2-) microsensors along with Ca2+ imaging to determine that irradiation induces Ca2+ influx and release in UC that activate NO• synthase (NOS). NO• binds to cytochrome oxidase, resulting in superoxide (*O2-) and ONO2- which inhibits mitochondrial respiration. This leads to swelling and rupture of the mitochondria, cytochrome c release and apoptosis. We developed a mitochondrial targeting strategy (U.S. Patent 11/565,779) for NOS antagonists and free radical scavengers, and mouse models where the bladder or descending colon is withdrawn through a small incision and selectively irradiated. These agents were radioprotective when intravesically instilled prior to bladder, but not colonic, irradiation (10 Gy; 1 Gy=100 rads). On the other hand, intracolonic administration of the antagonists blocked cross-sensitization and cystitis due to colonic irradiation. This suggests that pelvic organ cross-sensitization is involved in the development of radiation cystitis and that agents must be given systemically to afford multiple organ protection. In this proposal, we will investigate the mechanism for pelvic organ cross-sensitization, the channels involved in Ca2+ influx and release responsible for NOS activation and the benefits of new therapeutic agents to prevent or treat radiation cystitis. We have three specific aims that will be tested in control and transient receptor potential ankyrin 1 and vanilloid 1 (TRPA1-/- and TRPV1-/-) knockout mice using optical mapping of UC, dorsal root ganglia (DRG) neurons and afferent nerve terminals in the bladder wall and spinal cord. Cells and tissues will be stained with voltage- or Ca2+-sensitive dyes and/or afferent nerves labeled using pseudorabies virus (PRV369 and PRV823) expressing the genetically encoded Ca2+ indicator, GCaMP4. TRPA1-/- and TRPV1-/- mice will be used to determine the roles of these channels in irradiation-induced damage and HPLC-MS will be used to identify irradiation-induced electrophilic fatty acid derivatives (EFAD) involved in TRPA1 and TRPV1 channel activation. The therapeutic benefits of nitro-fatty acids (FA-NO2) and brain-derived neurotrophic factor- and nerve growth factor-antibodies (BDNF-AB and NGF-AB) will be tested. Our three specific aims and associated hypotheses are: 1 Determine the mechanism of bladder-colon afferent cross-sensitization that contributes to radiation cystitis. Hypothesis: Cystitis can develop from colonic irradiation due to cross-sensitization of divergent afferent nerves in the periphery or convergent ones in the spinal cord. 2 Determine the roles of TRPA1 and TRPV1 in irradiation-induced urothelial damage and afferent sensitization. Hypothesis: Irradiation produces EFAD that activate TRPA1 and TRPV1 ion channels resulting in UC damage and afferent sensitization. 3 Determine the therapeutic benefits of new agents for the prevention or treatment of radiation cystitis. Hypothesis: FA-NO2 are radioprotective by desensitizing TRPA1 and TRPV1 channels and BDNF-AB and NGF-AB are therapeutic by inhibiting nerve growth and sensitization in bladder and spinal cord.

描述（由申请人提供）：根据美国癌症协会（Cancer Facts & Figures, 2012）估计，2012年美国男性和女性盆腔器官肿瘤分别占新诊断肿瘤的48%和21%。虽然辐照是治疗这些恶性肿瘤的关键疗法，但其剂量受到发展为放射性膀胱炎的可能性的限制。膀胱炎的急性期包括由尿路上皮细胞（UC）渗透性屏障的破坏和传入神经的敏化引起的炎症和膀胱过度活动。慢性期可在6-12个月内发展为血管内皮细胞损伤、缺血、胶原沉积和膀胱顺应性下降。