EFFECTS OF ORAL ESTRADIOL THERAPY ON OSTEOCLASTOGENESIS

这个子项目是许多研究子项目中利用 资源由NIH/NCRR资助的中心拨款提供。子项目和 调查员(PI)可能从NIH的另一个来源获得了主要资金， 并因此可以在其他清晰的条目中表示。列出的机构是 该中心不一定是调查人员的机构。 我们对雌激素调节骨细胞的机制的了解是不完整的。这个过程很重要，因为绝经后女性的雌激素丢失，可能在性腺功能低下的男性身上，会导致骨量相对较快地下降，并使易患骨质疏松症的人容易患上这种疾病。这个翻译项目是康涅狄格大学健康中心(UCHC)基础和临床科学家合作的结果，他们的工作重点是识别人类患骨质疏松症的机制。我们在这个试点项目中的具体目标是检验性激素充足和缺乏的老年男性和绝经后女性骨髓中发生的细胞和分子变化的差异，因为在小鼠身上的初步数据表明了这种激素的重要性。 在初步工作中，我们发现小鼠去卵巢后，骨髓细胞分化为破骨细胞的能力迅速增加，破骨细胞是介导骨吸收的细胞。这一发现表明，它调节了造血祖细胞分化为破骨细胞的能力，这一过程尚未得到充分研究。由于骨吸收增加似乎是雌激素停用对人类骨骼最早的已知影响，因此更好地了解这一过程可能会导致更有效的治疗男性和女性骨质疏松症的方法。 具体目标1：通过评估雌激素(E2)治疗前后的骨髓抽吸物，检查这三组老年男性中每一组的破骨潜能。 具体目的2：检测E_2治疗前后骨髓细胞中B淋巴细胞系发育和破骨细胞形成的参数，包括B淋巴细胞系发育的标志物，以及骨髓中早成熟B淋巴细胞的百分比。这些研究还将评估分离的(CD19和CD19-)骨髓细胞在有无核因子-kappa B受体激活剂(RANKL)和单核细胞集落刺激因子(M-CSF)处理的情况下在体外形成破骨细胞样细胞的能力。 特定目的3：检测已知的影响破骨细胞形成的因素在骨髓中的表达，包括RANKL的信使核糖核酸(RNA)、核因子-kappaB受体激活剂(RANK)、骨保护素(OPG)、M-CSF和M-CSF受体(c-FMS)。我们还将通过流式细胞仪检测RANK和c-FMS的蛋白水平。

This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. Our understanding of the mechanisms by which estrogens regulate bone cells are incomplete. This process is important because estrogen loss by women after menopause and probably in hypogonadal men produces a relatively rapid decrease in bone mass and predisposes susceptible individuals to the development of the disease osteoporosis. This translational project is the result of a collaboration between basic and clinical scientists at the University of Connecticut Health Center (UCHC) whose work focuses on the identification of the mechanisms by which human beings develop the disease osteoporosis. Our specific goal in this pilot project is to examine the differences in cellular and molecular changes that occur in the bone marrow of sex steroid-replete and deficient older men and postmenopausal women in response to estrogen, as preliminary data in mice demonstrates the importance of this hormone. In preliminary work we have found that ovariectomy in mice is rapidly followed by an increase in the ability of bone marrow cells to differentiate into osteoclasts, the cells that mediate bone resorption. This finding suggests that regulates the ability of hematopoietic precursor cells to differentiate into osteoclasts, a process that has not been adequately examined. Since increased rates of bone resorption appear to be the earliest known effects of estrogen withdrawal on the human skeleton, a better understanding of this process may lead to more effective therapies for the treatment of osteoporosis in both men and women. Specific Aim 1:Examine the osteoclastogenic potential of each of these three groups of older men by evaluation of bone marrow aspirates both before and after treatment with Estrogen (E2). Specific Aim 2: Examine parameters of B-lymphocyte lineage development and osteoclast formation in cells from bone marrow including markers of B-lymphocyte lineage development, and the percentage of early and mature B-lymphocytes in the bone marrow before and after E2 treatment. These studies will also evaluate the ability of fractionated (CD19+ and CD19-) bone marrow cells to form osteoclasts-like cells in vitro with and without treatment with receptor activator of NF-kappa B-ligand (RANKL) and monocyte- colony stimulating factor (M-CSF). Specific Aim 3: Examine the expression in the bone marrow of factors known to influence osteoclast formation including messenger ribonucleic acid (RNA) for RANKL, receptor activator of NF-kappa B (RANK), osteoprotegerin (OPG), M-CSF and the M-CSF receptor (c-Fms). We will also measure protein levels of RANK and c-Fms by flow cytometry.