Bladder Pain Gene Therapy with Pro-opiomelanocortin cDNA

描述（由申请人提供）：间质性膀胱炎（IC）是一种与膀胱疼痛相关的膀胱超敏性疾病，一直是理解和治疗的主要挑战。我们假设膀胱内源性阿片肽的靶向和局部表达可能对膀胱疼痛的治疗有用。促阿片黑素皮质素（POMC）是阿片肽-内啡肽的前体分子之一。在本R21资助申请中，利用我们最近开发的POMC cDNA基因枪在体内转移的方法，研究其对醋酸和环磷酰胺诱导的大鼠膀胱多动的有效性和安全性。将人POMC cDNA克隆到修饰的pCMV质粒中。我们将通过直接注射或基因枪将cDNA送入成年雌性大鼠膀胱壁。我们将用醋酸和环磷酰胺对急性和慢性膀胱多动模型进行短期和长期疗效评估。POMC cDNA转染后的内啡肽检测将采用膀胱造影和免疫组织化学检测。我们认为POMC基因可以通过基因枪转移到膀胱中，而内啡肽在膀胱中的表达增加可以抑制膀胱刺激引起的伤害性反应。因此，通过膀胱镜工作口输送的POMC基因枪可能对IC和其他类型的内脏疼痛的治疗有用。这个R21项目的长期目标是开发令人信服的数据，以证明在项目的两年时间框架内提交RO1是合理的。此外，我们希望建立一种安全有效的非病毒基因治疗膀胱疼痛综合征的概念。本课题的研究为今后的临床应用提供了坚实的基础。

DESCRIPTION (provided by applicant): Interstitial cystitis (IC) is a bladder hypersensitivity disease associated with bladder pain, which has been a major challenge to understand and treat. We hypothesize that targeted and localized expression of endogenous opioid peptide in the bladder could be useful for the treatment of bladder pain. Pro-opiomelanocortin (POMC) is one of such precursor molecules for an opioid peptide, beta-endorphin. In this R21 grant proposal, using a gene-gun method for the transfer of POMC cDNA in vivo that we have recently developed, and investigated its efficacy and safety on acetic acid and cyclophosphamid-induced bladder hyperactivity in the rats. Human POMC cDNA was cloned into a modified pCMV plasmid. We will deliver the cDNA into the bladder wall of adult female rats by direct injection or gene-gun. We will evaluate short and long-term effects of this form of therapy with acute and chronic bladder hyperactivity models using acetic acid and cyclophosphamid. Physiological testing with cystometrograms and immunohistochemical testing will be used to detect endorphin after POMC cDNA transfer. We believe that POMC gene can be transferred in the bladder using gene-gun and that increased expression of endorphin in the bladder can suppress nociceptive responses induced by bladder irritation. Thus POMC gene-gun, delivered through the working port of a cystoscope, may be useful for the treatment of IC and other types of visceral pain. The long-term objective of this R21 project is to develop convincing data to justify a RO1 submission within the two years time frame of the project. Moreover, we want to establish a safe and effective concept of nonviral gene therapy for the treatment of the painful bladder syndromes. This research project is important to provide a solid basis for potential future clinical application.