SEX STEROIDS, GROWTH FACTORS AND BONE CELL FUNCTION

性类固醇、生长因子和骨细胞功能

• 批准号: 6338594
• 负责人: THOMAS C SPELSBERG
• 金额: $ 33.49万
• 依托单位: MAYO CLINIC ROCHESTER
• 依托单位国家: 美国
• 财政年份: 2000
• 资助国家: 美国
• 起止时间: 2000-08-15 至 2001-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6338594
• 关键词: aging; bone metabolism; cell cycle; cell differentiation; cell growth regulation; cell line; cell proliferation; cytokine; estrogen receptors; estrogens; extracellular matrix proteins; gel electrophoresis; gene expression; hormone regulation /control mechanism; human genetic material tag; human tissue; messenger RNA; normal ossification; osteoblasts; osteoclasts; physiologic bone resorption; receptor expression; regulatory gene; tamoxifen; tissue /cell culture

Although estrogen (E) administration prevents bone loss and osteoporosis in postmenopausal women, the mechanism of its action at the cellular and molecular level remains unclear. The osteoblasts (OB) have been shown by many laboratories to contain estrogen receptors (ER) and to be target cells for E, but the exact actions of E on bone cells have been obscured by varying concentrations of ER and E responses between different OB cell lines. The roles of the ER-beta species and progesterone (P) in OB cells further complicate the issue. In order to discern the effects that the varying concentrations of ER and the ER-alpha and beta species have on the biological actions on E on OB cells, our laboratories have generated and characterized over a dozen conditionally immortalized, mature, human OB cell lines (hFOB) which display normal OB-like properties. These cells have been stably transfected to express varying levels pf ER-alpha (hFOB/ER-alpha), ER-beta (hFOB/ER-beta), or both species, and several express endogenous PR. We have also developed and characterized six lines of immortalized precursor cells from human bone marrow stroma 9hMS), which can differentiate into either the OB ro adipocyte phenotype. These hFOB/ER and hMS cell lines will be used to answer the following questions: 1) are mature OB or their precursors potential target cells for E, and if so, what concentrations of ER and which ER species (alpha or beta) are required for the regulation of early and late genes, including cytokines and bone matrix proteins, as well as OB functions, such as cell proliferation, matrix production, and mineralization; 2) are both PRA and PRB species expressed in the OB or their precursor cells, does the PRA:PRB ratio change during OB differentiation and differ among the ER-alpha or ER-beta containing cells, and which genes/processes do these PR species regulate; 3) do E and P regulate OB precursor cell (hMS) differentiation, including gene expression; and finally 4) are the potent new OB-derived soluble, neutralizing receptor, osteoprotegrin, and its ligand (OPGL), regulated by E in the hFOB/ER cells and do they in turn mediate the E action on osteoclast cell differentiation and activity.

虽然雌激素（E）的管理，防止绝经后妇女的骨丢失和骨质疏松症，其作用机制在细胞和分子水平仍不清楚。 许多实验室已经证明成骨细胞（OB）含有雌激素受体（ER）并且是E的靶细胞，但是由于不同OB细胞系之间不同浓度的ER和E反应，E对骨细胞的确切作用已经被模糊。 ER-β物质和孕酮（P）在OB细胞中的作用使问题进一步复杂化。 为了辨别不同浓度的ER以及ER-α和β物质对OB细胞上的E的生物学作用的影响，我们的实验室已经产生并表征了十几种显示正常OB样特性的条件永生化的成熟人OB细胞系（hFOB）。 这些细胞已被稳定转染，表达不同水平的ER-α（hFOB/ER-α），ER-β（hFOB/ER-β），或这两种物种，和一些表达内源性PR。我们还开发和表征了六个线的永生化前体细胞从人骨髓基质9 hMS），它可以分化成OB或脂肪细胞表型。 这些hFOB/ER和hMS细胞系将用于回答以下问题：1）成熟OB或其前体细胞是否是E的潜在靶细胞，如果是，什么浓度的ER和哪种ER（α或β）是调节早期和晚期基因所必需的，包括细胞因子和骨基质蛋白，以及OB功能，如细胞增殖、基质产生和矿化; 2）PRA和PRB种类是否都在OB或其前体细胞中表达，PRA：PRB比率在OB分化期间是否改变并且在含有ER-α或ER-β的细胞中是否不同，以及这些PR种类调节哪些基因/过程; 3）E和P调节OB前体细胞（hMS）分化，包括基因表达;和最后4）是有效的新OB衍生的可溶性中和受体，骨保护素，及其配体（OPGL），在hFOB/ER细胞中受E调节，并且它们反过来介导E对破骨细胞分化和活性的作用。