ANDROGEN REGULATION OF HUMAN SEBACEOUS GLANDS

这个指导研究计划的总体目标是提供 P.I.有机会进一步发展认知，技术 和口译技能，以实现她的职业目标， 临床实践与基础研究。的具体目标 提出的实验是为了阐明雄激素在控制 皮脂腺（SG）的发育和分化。雄激素 被认为是调节由SG产生的皮脂，从而， 有助于寻常痤疮，一种流行病的发展 与严重的身体和心理疾病有关。 了解调节SG生长和脂肪生成的机制， 雄激素是必不可少的发展合理的战略，以控制 皮脂产生和痤疮。为了描述这些机制 我们已经建立了一个器官型培养（组织培养）系统， 在存在和不存在它们的天然SG的情况下繁殖完整的人SG 真皮成纤维细胞操纵这个系统，使用雄激素， 雄激素代谢酶和生长因子的抑制剂，和 组织特异性核酶构建体，以选择性地防止 翻译个人成绩单，将使我们能够测试 以下假设：i）睾酮转化为 通过成纤维细胞和皮脂腺细胞中的1型5a-还原酶的双氢睾酮 是调节SG生长和脂质的必要步骤 ii）SG的生长和脂质产生受以下因素调节： 生长因子和雄激素之间的旁分泌相互作用。我们将 确定雄激素是否仅直接或间接作用于SG 通过真皮成纤维细胞。成纤维细胞是否应该被证明参与 介导雄激素对SG生长和脂质产生的某些作用， 我们将确定成纤维细胞产生的生长因子， 特别是表皮生长因子、胰岛素样生长因子-I， 角质形成细胞生长因子参与了这一过程。终点 评估皮脂腺生长将包括，3 H掺入 胸苷、Ki-67免疫细胞化学和组织学。脂肪生成将 通过将14 C-乙酸盐掺入脂质中测定。 参与代谢的每种酶的药理学抑制剂 雄激素的代谢，并且已知其在人类中表达。 SG，将被用来确定个别C-19类固醇的作用， 通过SG调节生长和脂质产生的特定方面。 15 α-还原酶、雄激素受体和生长作用的结果 感兴趣的因素将通过分离皮脂细胞来确认， 真皮成纤维细胞与含有新的三重核酶的构建体， 由组织特异性启动子驱动， 酶、受体或肽的转录物。

The overall goal of this mentored research program is to provide the P.I. with the opportunity to develop further the cognitive, technical and interpretive skills required to pursue her career goal of combining clinical practice with basic research. The specific goal of the experiments proposed is to elucidate androgens' role in controlling the development and differentiation of the sebaceous gland (SG). Androgens are thought to modulate sebum production by the SG and, thereby, to contribute to the development of acne vulgaris, a prevalent disease associated with significant physical and psychological morbidity. Understanding the mechanisms regulating SG growth and lipogenesis by androgens is essential for developing rationale strategies to control sebum production and acne. In order to characterize these mechanisms we have established an organotypic culture (histoculture) system for propagating intact human SG in the presence and absence of their native dermal fibroblasts. Manipulating this system, using androgens, inhibitors of androgen metabolizing enzymes and growth factors, and tissue specific ribozyme constructs to prevent selectively the translation of individual transcripts, will enable us to test the following hypotheses: i) Conversion of testosterone to dihydrotestosterone by type 1 5a-reductase in fibroblasts and sebocytes is an obligatory step in the modulation of SG growth and lipid production and; ii) Growth and lipid production of SG is regulated by paracrine interactions between growth factors and androgens. We will determine if androgens act on the SG only directly, or also indirectly via dermal fibroblasts. Should fibroblasts prove to be involved in mediating some actions of androgens on SG growth and lipid production, we will determine if growth factors generated by fibroblasts, specifically epidermal growth factor, insulin-like growth factor-I and keratinocyte growth factor, are involved in this process. Endpoints for assessing sebaceous gland growth will include, incorporation of 3H thymidine, Ki-67 immunocytochemistry and histology. Lipogenesis will be determined using incorporation of 14C-acetate into lipids. Pharmacological inhibitors of each of the enzymes involved in the metabolism of androgens, and which are known to be expressed in human SG, will be used to identify the role of individual C-19 steroids in modulating specific aspects of growth and lipid production by SG. Results on the role of 1 5alpha-reductase, androgen receptor and growth factor of interest will be confirmed by transfecting sebocytes and dermal fibroblasts with a construct containing a novel triple ribozyme, driven by tissue-specific promoters, which will selectively cleave transcript for the enzyme, receptor or peptide.