The Osteoblastic Monolayer as a 'Gatekeeper' in Bone

成骨细胞单层作为骨骼的“看门人”

• 批准号: 6662547
• 负责人: MELISSA L KNOTHE TATE
• 金额: $ 7.38万
• 依托单位: CLEVELAND CLINIC FOUNDATION
• 依托单位国家: 美国
• 财政年份: 2002
• 资助国家: 美国
• 起止时间: 2002-09-23 至 2005-05-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6662547
• 关键词: bone development; bone metabolism; calcium flux; cell line; cell membrane; confocal scanning microscopy; diffusion; electrical conductance; electrophysiology; glucose transport; insulin; membrane channels; membrane model; membrane permeability; membrane potentials; model design /development; osteoblasts; parathyroid hormones; phosphates

DESCRIPTION (provided by applicant): The broad, long-term objective of this project is to understand the barrier properties of a confluent osteoblastic monolayer, which will provide insight into the role of the osteoblastic lining cell system in the physiology and pathophysiology of bone. This layer of cells that covers all resting surfaces in bone is expected to serve a "gatekeeper" role in the development of hydraulic and electric resistance as well as passage of material, e.g., water, nutrients, ions, waste products and growth factors, into and out of bone tissue. It is this gatekeeper role that lends bone the ability to function as an organ within vertebrate systems. The Specific Aims of this project are (1) to study the permeability characteristics of water as well as specific nutrients (glucose), ions (calcium and phosphate) and growth factors (insulin, PTH) in a static environment, allowing for simple diffusion and pressure head differences between the apical and basal surfaces as well as (2) in dynamic environments exposed to cyclic flow regimes on the apical and basal surfaces of the membrane. For each of these aims, the effect of PTH on barrier function will be studied in situ. The research design is to measure baseline values for hydraulic and electrical conductivity as well as concentration gradients of water, nutrient (glucose), ion (Ca and P) and growth factor transport (insulin, and PTH or a fluorescent tagged, inert analog such as dextran) due to diffusion and static pressure across the osteoblast cell membrane. A confluent monolayer of osteoblasts from the paraosteosarcoma cell line UMR-106-01-BSP will be used as a model system. To address the first aim, pressure will be provided through a pressure head on either side of the membrane in an Ussing chamber. To address the second aim, an innovative dual flow chamber system will be built, tested and implemented as a physiological cell culture model. In both cases, electrical resistance and hydraulic conductance will be measured across the membrane, and glucose, calcium, phosphate, PTH and insulin will be measured in the apical and basal media. The proposed project represents an innovative departure from conventional understanding of bone physiology. This study is expected to provide insight into new strategies for treatment of bone diseases such as osteoporosis and osteoarthritis.

描述（由申请人提供）： 该项目的广泛长期目标是了解融合成骨细胞单层的障碍特性，该单层将洞悉成骨细胞内膜细胞系统在骨骼生理学和病理生理学中的作用。覆盖骨骼中所有静止表面的细胞层有望在液压和电阻的发展中起“看门人”的作用，以及材料的传递，例如水，营养素，离子，废物，废物产物和生长因子，进入骨组织。正是这种守门人的角色使骨骼在脊椎动物系统中充当器官的能力。 The Specific Aims of this project are (1) to study the permeability characteristics of water as well as specific nutrients (glucose), ions (calcium and phosphate) and growth factors (insulin, PTH) in a static environment, allowing for simple diffusion and pressure head differences between the apical and basal surfaces as well as (2) in dynamic environments exposed to cyclic flow regimes on the apical and basal surfaces of the膜。对于这些目标，将在原位研究PTH对屏障功能的影响。研究设计是为了测量水力和电导率的基线值以及水，养分（葡萄糖），离子（CA和P）的浓度梯度以及生长因子转运（胰岛素和PTH或荧光标记，惰性类似物，例如右旋烷（例如右旋）），这是由于扩散和静态压力跨膜素细胞覆盖了骨质细胞的。来自paraosteosarcoma细胞系UMR-106-01-BSP的成骨细胞的汇合单层将用作模型系统。为了解决第一个目标，将通过USSSing室中膜任一侧的压力头提供压力。为了解决第二个目标，将作为生理细胞培养模型建立，测试和实施创新的双流室系统。在这两种情况下，将在整个膜上测量电阻和液压电导，葡萄糖，钙，磷酸盐，PTH和胰岛素将在顶端和基础培养基中测量。拟议的项目代表了与骨生理的常规理解的创新性不同。这项研究有望洞悉治疗骨质疏松症和骨关节炎等骨骼疾病的新策略。