TGF-beta1 activity in the aortic valve

描述(由申请人提供)：本提案的目标是将应聘者在细胞和组织力学方面的专业知识与转化生长因子-(31)活性和心血管病理生理学的分子机制相结合，以适当地检查主动脉瓣(AV)硬化。候选人将由Joanne E.Murphy-Ullrich博士和Louis J.Dell‘ltalia博士共同指导，Joanne E.Murphy-Ullrich博士是转化生长因子-01激活和活性的分子机制专家，Louis J.Dell’ltalia博士是心血管生理学、瓣膜疾病和左心室重构的专家。该奖项期间的培训包括授课工作、在导师和共同导师的实验室中轮换，以及定期会议、研讨会和期刊俱乐部。这种有指导的培训对于候选人调查拟议的研究和制定未来NIH生物医学研究的资金提案是必不可少的。 最近，我们发现同时暴露于循环应变和生物活性转化生长因子-01的主动脉瓣(AV)小叶导致主动脉瓣间质细胞(AVICs)向肌成纤维细胞的表型协同转变，胶原生成增加，总(潜伏期+生物活性)转化生长因子-β1的表达较单独刺激增加11倍，这表明AVIC株与转化生长因子-01信号之间存在正向相互作用(Merryman，心血管病理学，2007)。然而，机械应变调节房室内转化生长因子-01活性的机制尚不清楚。我们认为，房室硬化的自然进展是由于机械依赖的转化生长因子-(31)信号的改变，导致细胞变形增加。因此，我们假设转化生长因子-31的合成和/或生物激活的调节依赖于细胞应变，从而导致动静脉动静脉内皮细胞、改变的ECM和动静脉曲张硬化的表型变化。我们将通过以下目标来检验这一假设： 具体目的1-定量研究血管内皮细胞单层培养中转化生长因子-01的合成和生物活性对生理和病理生理环境的依赖性。 特定目的2-原位定量生理和病理生理条件下血管内皮细胞转化生长因子-β1的合成和活性。

DESCRIPTION (provided by applicant): The goal of this proposal is to synthesize the Candidate's expertise in cell and tissue mechanics with the molecular mechanisms of TGF-(31 activity and cardiovascular pathophysiology to appropriately examine aortic valve (AV) sclerosis. The Candidate will be mentored by Dr. Joanne E. Murphy-Ullrich, an expert in molecular mechanisms of TGF-01 activation and activity, and co-mentored by Dr. Louis J. Dell'ltalia, an expert in cardiovascular physiology, valvular disease, and left ventricle remodeling. Training during this award includes didactic course work, rotations in the laboratories of the mentor and co-mentor, and regular meetings, seminars, and journal clubs. This mentored training is essential for the Candidate to investigate the proposed research and develop future NIH funding proposals in biomedical research. Recently, we found that aortic valve (AV) leaflets exposed to both cyclic strain and bioactive TGF-01 resulted in a synergistic phenotypic shift of aortic valve interstitial cells (AVICs) to myofibroblasts with increased collagen production and 11-fold increase in total (latent + bioactive) TGF-P1 expression compared to either stimulus alone, suggesting positive interactions between AVIC strain and TGF-01 signaling (Merryman, Cardiovascular Pathology, 2007). However, the mechanisms by which mechanical strain regulate TGF-01 activity in the AV are unknown. We propose that the natural progression of AV sclerosis is due to altered mechano-dependent signaling of TGF-(31 by AVICs subjected to increased cellular deformation. Thus, we hypothesize that regulation of TGF-31 synthesis and/or bioactivation is dependent on cellular strain, leading to phenotypic changes of the AVICs, altered ECM, and AV sclerosis. We will test this hypothesis with the following aims: Specific Aim 1 - Quantify the dependence of TGF-01 synthesis and bioactivation on physiologic and pathophysiologic strain environments in monolayer culture of AVICs. Specific Aim 2 - Quantify TGF-p1 synthesis and bioactivation from AVICs under physiologic and pathophysiologic strains in situ.