IMPACT OF MENOPAUSE ON VAGINAL CONNECTIVE TISSUE SUPPORT

描述（由申请人提供）：阴道结缔组织支撑的丧失导致盆腔脏器脱垂到阴道管中。脱垂和脱垂的后遗症对数百万妇女的生活产生了深远的负面影响。在美国，11%的女性将接受一次大的外科手术来修复脱垂，30%的女性因手术失败而需要再次手术。到目前为止，大多数研究都集中在分娩是脱垂的主要危险因素；然而，大多数妇女直到分娩后几十年才出现脱垂，这表明其他因素也起作用（4,6,35 -38）。在这项修订后的拨款申请中，我们收集了一个多学科专家团队，通过对更年期对阴道支持性结缔组织的影响进行全面分析，研究更年期作为脱垂的危险因素。在目的I-1和1-2中，我们建议比较未接受激素治疗的绝经前妇女和绝经后妇女阴道支持性结缔组织的活检，以测试未接受激素治疗的绝经后妇女的胶原比率[I/(III + V)]的降低是否导致生物力学性能低下和易脱垂。此外，我们确定弹性蛋白和/或平滑肌相对于胶原蛋白的数量变化是否与生物力学的恶化相关。最后，在本部分的拨款中，我们询问绝经后妇女的激素治疗是否改善了未接受激素治疗的绝经后妇女阴道结缔组织中发现的结构和生物力学缺陷。在Aim II-1中，我们将研究阴道结缔组织这些结构成分的变化是否由于结缔组织降解基质金属蛋白酶（MMPs）相对于其内源性抑制剂（MMPs的组织抑制剂，TIMPs）的表达和活性模式的改变。我们用生化测定法测量单个金属蛋白酶的表达和活性，用底物降解测定法测量组织中的净蛋白水解活性。研究了17- β -雌二醇+/-孕酮对阴道结缔组织细胞MMP/TIMP表达的调控机制。由于人体组织研究固有的局限性，我们在Aims III-1和111-2中使用大鼠模型，以确定补充17- β -雌二醇、17- β -雌二醇和黄体酮或MMP抑制剂-化学修饰四环素-8是否能防止中年大鼠手术诱导绝经后阴道结缔组织生物力学性能的恶化。我们有令人兴奋的初步数据来支持研究中概述的每一个目标。我们相信，这一修订后的拨款提案的结果将阐明使妇女易患阴道壁脱垂的重要机制，并最终有助于制定预防策略来治疗这种常见的、使人衰弱的、但尚未得到充分研究的疾病。

DESCRIPTION (provided by applicant): Loss of the vaginal connective tissue support results in prolapse of the pelvic viscera into the vaginal canal. Prolapse and the sequela of prolapse have a profoundly negative impact on the lives of millions of women. Eleven percent of women in the United States will undergo a major surgical procedure to repair prolapse and 30% require re-operation because of failure (4). Until now, most studies have focused on childbirth as the primary risk factor for developing prolapse; however, the majority of women do not develop prolapse until decades following childbirth indicating that other factors play a role (4-6, 35-38). In this revised grant application, we have collected a multidisciplinary team of experts to study menopause as a risk factor for prolapse by performing a comprehensive analysis of the impact of menopause on the supportive connective tissue of the vagina. In Aims I-1 and 1-2, we propose to compare biopsies of vaginal supportive connective tissue in premenopausal and postmenopausal women not on hormone therapy to test whether a decrease in the ratios of collagen [I/(III + V)] in postmenopausal women not on hormone therapy leads to inferior biomechanical properties and predisposes to prolapse. In addition, we determine whether quantitative changes in the amount of elastin and/or smooth muscle relative to collagen correlate with a deterioration in biomechanics. Finally, in this section of the grant, we ask whether hormone therapy in postmenopausal women improves the structural and biomechanical deficiencies identified in the vaginal connective tissue of postmenopausal women not on hormone therapy. In Aim II-1, we will investigate whether the changes in these structural components of the vaginal connective tissue are due to an alteration in the expression and activity pattern of the connective tissue degrading Matrix Metalloproteinases (MMPs) relative to their endogenous inhibitors (Tissue Inhibitors of MMPs, TIMPs). We measure the expression and activity of individual metalloproteinases using biochemical assays and net proteolytic activity in tissue using substrate degradation assays. The mechanism of regulation of MMP/TIMP expression by 17-beta-estradiol +/- progesterone is studied, in parallel, in cells derived from the supportive vaginal connective tissue in culture. Because of the limitations inherent in studies on human tissues, we use a rat model in Aims III-1 and 111-2, to determine whether supplementation with 17-beta-estradiol, 17-beta-estradiol and progesterone or the MMP inhibitor - chemically modified tetracycline-8, prevents the deterioration in the biomechanical properties of the vaginal connective tissue that occur following a surgically induced menopause in middle aged rats. We have exciting preliminary data to support each of the Aims outlined in the study. We believe that the results of this revised grant proposal will elucidate an important mechanism that predisposes women to vaginal wall prolapse and will ultimately contribute to the development of preventative strategies to treat this common and debilitating, yet vastly understudied disease.