Physical Strain & Hypertrophic Scar--Integrin Signaling

身体压力

• 批准号: 6339979
• 负责人: Howard Levinson
• 金额: $ 4.38万
• 依托单位: PENNSYLVANIA STATE UNIV HERSHEY MED CTR
• 依托单位国家: 美国
• 财政年份: 2001
• 资助国家: 美国
• 起止时间: 2001-07-01 至
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/6339979
• 关键词: actin binding protein; biological signal transduction; collagen; densitometry; enzyme activity; enzyme inhibitors; fibroblasts; focal adhesion kinase; genetic strain; genistein; immunocytochemistry; immunoprecipitation; integrins; intermolecular interaction; laboratory mouse; myosin light chain kinase; phosphorylation; protein tyrosine phosphatase; scars; tissue /cell culture; vanadium; western blottings; wound healing

The disfiguring, dysfunctional hypertrophic scar (HS) in the highly strained tissue of a badly burned patient leaves an indelible impression. It is not well understood how high tissue-tension promotes HS, but it is clear that environmental strain regulates fibroblast gene expression, fibroblast alignment and extracellular matrix (ECM) morphology through integrin linked cell-cell and cell ECM interactions. Conformational changes in integrins mediate focal adhesion kinase (FAK) activation and subsequent phosphorylation of tyrosine residues. Therefore, FAK and associated proteins likely play a pivotal role in HS formation. The broad long-term objective of the project is to unravel the signaling pathways underlying strain induced HS growth. The hypothesis to be tested is mechanical strain promotion of HS formation in healed wounds. A novel in vitro mechanical strain device and tight-skin mouse wound-healing model will be used to investigate three aims: (1) Compare temporal phosphorylation patterning of beta1 integrin, FAK, and talin and myosin light chain kinase activation in mechanically strained HS, normal human scar and normal human dermal fibroblasts (NHDF). (2) Describe how tyrosine kinase inhibition affects phosphorylation of beta1, integrin, FAK, and talin tyrosine phosphorylation and MLCK activity in physically strained HS, normal human scar and NHDF. (3) Document how systemic administration of the tyrosine phosphatase inhibitor, orthovanadate, affects HS-like nodule myofibroblast formation and wound contraction in tight-skin mouse wounds and compare to matched normal mouse wounds.

严重烧伤患者高度紧张的组织中的毁容、功能失调的增生性瘢痕（HS）会留下不可磨灭的印象。尚不清楚高组织张力如何促进HS，但很明显，环境应变通过整合素连接的细胞-细胞和细胞ECM相互作用调节成纤维细胞基因表达、成纤维细胞排列和细胞外基质（ECM）形态。整合素的构象变化介导粘着斑激酶（FAK）活化和随后的酪氨酸残基磷酸化。因此，FAK和相关蛋白可能在HS形成中起关键作用。该项目广泛的长期目标是解开应变诱导HS生长的信号通路。待检验的假设是愈合伤口中HS形成的机械应变促进。本研究采用一种新型的体外机械应变装置和小鼠皮肤紧绷伤口愈合模型，研究三个目的：（1）比较机械应变的HS、正常人瘢痕和正常人皮肤成纤维细胞（NHDF）中β 1整合素、FAK和talin的时间磷酸化模式以及肌球蛋白轻链激酶的激活。(2)描述酪氨酸激酶抑制如何影响物理紧张的HS、正常人瘢痕和NHDF中β 1、整联蛋白、FAK和talin酪氨酸磷酸化和MLCK活性的磷酸化。(3)记录酪氨酸磷酸酶抑制剂原钒酸盐的全身给药如何影响致密皮肤小鼠伤口中HS样结节肌成纤维细胞形成和伤口收缩，并与匹配的正常小鼠伤口进行比较。