Water vs. mineral-collagen interaction in bone

水与骨骼中矿物质-胶原蛋白的相互作用

• 批准号: 7773938
• 负责人: Xiaodu Wang
• 金额: $ 17.47万
• 依托单位: UNIVERSITY OF TEXAS SAN ANTONIO
• 依托单位国家: 美国
• 财政年份: 2010
• 资助国家: 美国
• 起止时间: 2010-06-01 至 2012-05-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7773938
• 关键词: Address; Affect; Age; Aging; Alcohols; Architecture; Arts; Atomic Force Microscopy; Behavior; Binding; Bone Tissue; Carbon Tetrachloride; Clinical; Collagen; Dehydration; Dentin; Deuterium Oxide; Dimethylformamide; Elderly; Experimental Designs; Failure; Fracture; Healthcare; Human; Hydrogen Bonding; Ions; Lead; Liquid substance; Mechanics; Minerals; Morbidity - disease rate; Pathway interactions; Phase; Plasticizers; Play; Population; Predisposition; Process; Property; Protocols documentation; Role; Sampling; Solutions; Specimen; Surface; Techniques; Testing; Tissue Banking; Tissue Banks; Tissues; Water; Work; age related; base; bone; bone mass; bone quality; bone toughness; cohesion; high risk; interfacial; male; mechanical behavior; middle age; mortality; nanoprobe; novel; public health relevance; response; skeletal; van der Waals force

DESCRIPTION (provided by applicant): Skeletal fractures are a major health care concern of elderly populations due to deteriorated bone quality, which is dependent on the properties and spatial arrangement of bone constituents (i.e., mineral, collagen and water). Among them, water has been identified to distribute in bone in three major forms: mobile water (in pores), loosely bound water (attached to mineral and collagen surfaces), and tightly bound water (as part of mineral and collagen molecules). It has been well known that dehydration of bone significantly reduces the toughness of the tissue, suggesting that interactions of water with the other bone constituents (i.e., mineral and collagen) play a significant role in bone toughness. Relevant to clinical concerns, recent findings indicate that the toughening effect of water diminishes with aging, suggesting that age-related changes may somehow block the pathway(s) for water to function as a plasticizer in bone. In general, water molecules may interact with mineral and collagen phases in two major ways: polar interactions (van der Waals forces) and much stronger hydrogen bonds. Thus, it is important to understand how such interactions (polar interaction and hydrogen bond) with the mineral and collagen phases by water are involved in toughening of bone tissues. Previous evidence has shown that the interaction of water with the mineral and collagen phases could inflict significant impacts on the mechanical behavior of bone. To this end, we propose in this exploratory proposal to study the contribution of polar interactions and hydrogen bonding ability of water to the mechanical behavior of bone using a novel experimental design and state-of-the-art techniques. Such understanding will help decipher the role of water in sustaining the toughness of bone and further facilitate the understanding of age-related changes in bone ultrastructure that obstruct the contribution of water to the tissue toughness. The hypothesis of this study is that water molecules affect the interaction between the mineral and collagen phases through both polar interactions and hydrogen bonding, thus imposing a significant effect on the toughness of bone. To test the hypothesis, two specific aims will be addressed: 1) to determine the effect of polar (van der Waals) forces and hydrogen bonding ability of water molecules on the interaction between the mineral and collagen phases; and 2) to determine the effect of polar (van der Waals) interactions and hydrogen bonding ability of water molecules on the mechanical behavior of bone. Combining the results obtained from Aim 1 and 2, the role of water in sustaining the toughness of bone will be elucidated. PUBLIC HEALTH RELEVANCE: Previous evidence has indicated that the role of water in sustaining the toughness of bone diminishes with increasing age. A systematic study using start-of-the-art techniques is proposed to elucidate the toughening mechanism of water to bone at ultrastructural levels. Such understanding will assist elucidate age-related changes in bone ultrastructure and its correlation with age-related bone fractures.

描述（由申请人提供）：由于骨质恶化，骨质恶化取决于骨成分的性质和空间排列（即，矿物质、胶原蛋白和水）。其中，水已被确定以三种主要形式分布在骨中：移动的水（在孔隙中）、松散结合的水（附着于矿物质和胶原蛋白表面）和紧密结合的水（作为矿物质和胶原蛋白分子的一部分）。众所周知，骨的脱水显著降低了组织的韧性，这表明水与其他骨成分（即，矿物质和胶原蛋白）在骨韧性中起重要作用。与临床问题相关的是，最近的研究结果表明，水的增韧作用随着年龄的增长而减弱，这表明与年龄相关的变化可能会以某种方式阻断水作为骨中增塑剂的途径。通常，水分子可以以两种主要方式与矿物质和胶原相相互作用：极性相互作用（货车德瓦尔斯力）和更强的氢键。因此，重要的是要了解这种相互作用（极性相互作用和氢键）与矿物和胶原相的水是如何参与骨组织的韧化。先前的证据表明，水与矿物质和胶原相的相互作用可以对骨的力学行为产生显著影响。为此，我们建议在这个探索性的建议，研究极性相互作用和氢键的能力，骨的力学行为的贡献，使用一种新的实验设计和国家的最先进的技术。这种理解将有助于破译水在维持骨韧性中的作用，并进一步促进对骨超微结构中与年龄相关的变化的理解，这些变化阻碍了水对组织韧性的贡献。本研究的假设是，水分子通过极性相互作用和氢键作用影响矿物相和胶原相之间的相互作用，从而对骨的韧性产生显著影响。为了验证这一假设，将解决两个具体目标：1）确定极性（货车德瓦尔斯）力和水分子的氢键结合能力对矿物相和胶原相之间的相互作用的影响; 2）确定极性（货车德瓦尔斯）相互作用和水分子的氢键结合能力对骨的力学行为的影响。结合目标1和目标2的结果，将阐明水在维持骨韧性中的作用。 公共卫生相关性：以前的证据表明，水在维持骨骼韧性方面的作用随着年龄的增长而减弱。本研究采用最先进的技术，在超微结构水平上阐明了水对骨的增韧机制。这些认识将有助于阐明骨超微结构的年龄相关性变化及其与年龄相关性骨折的关系。