Differential changes in energy metabolism in response to mechanical tension give rise to human scaring heterogeneity

响应机械张力的能量代谢的差异变化导致人类恐惧异质性

基本信息

批准号：
10660416
负责人：
Swathi Balaji
金额：
$ 32.08万
依托单位：
BAYLOR COLLEGE OF MEDICINE
依托单位国家：
美国
项目类别：
财政年份：
2023
资助国家：
美国
起止时间：
2023-07-01 至 2028-03-31
项目状态：
未结题

来源：
https://reporter.nih.gov/project-details/10660416
关键词：
Actins Address Bioenergetics Biological Models Biomechanics Cell Proliferation Cells Cicatrix Clinical Collagen Communication Cytoskeleton Data Deposition Dermal Development Dimerization Disease Economic Burden Energy Metabolism Enzymes Extracellular Matrix Fibroblasts Fibrosis Foundations Glycolysis Healthcare Heterogeneity Human In Vitro Individual Inflammatory Injury Invaded Knowledge Lead Link Malignant Neoplasms Mechanics Mediating Mediator Metabolic Metabolic Pathway Metabolism Mitochondria Molecular Chaperones Morbidity - disease rate Mus Natural regeneration Organ Outcome Oxidative Phosphorylation Oxidative Stress Oxygen Pathway interactions Patients Phenotype Phosphorylation Phosphotransferases Physiological Predisposition Process Production Proliferating Proteome Regulation Research Role Scleroderma Signal Transduction Skin Skin injury Source Testing Therapeutic Transforming Growth Factor beta Transplantation Validation Variant Warburg Effect Wound models Xenograft Model Xenograft procedure aerobic glycolysis antifibrotic treatment biobank career clinically relevant design dimer experimental study gain of function healing improved in vivo loss of function mechanical signal mechanotransduction metabolic profile migration novel novel therapeutics organ injury p38 Mitogen Activated Protein Kinase predictive modeling prevent psychosocial regenerative response response to injury skin regeneration stem tissue repair transcriptomics whole genome wound wound healing

项目摘要

PROJECT SUMMARY Dermal injury leads to fibrosis and scar formation, which can be a significant source of morbidity. Interestingly, humans respond to identical skin injuries with different degrees of scar formation that range from low to high scaring phenotypes. Understanding the mechanisms that drive heterogeneous scarring outcomes will allow us to design strategies to direct wound healing toward regeneration and reduced scarring. Biomechanical forces are known to influence how the skin heals. Biomechanical tension signals fibroblast proliferation, migration, inflammatory functions and production of extracellular matrix (ECM). These responses, in conjunction with oxidative stress in the wound, place a high energy demand on fibroblasts. Typically, metabolic requirements of cells are met via mitochondrial oxidative phosphorylation (OXPHOS) under homeostatic conditions or via glycolysis when oxygen is limited. Recent studies have shown that increase in mechanical cues can alter energy metabolism by promoting glycolysis. Notably, the phenomenon of a metabolic shift towards ‘aerobic glycolysis’ (Warburg effect) was mainly described in progression of fibrotic diseases, but our data showed that fibroblasts from uninjured skin of healthy patients with high scarring phenotype (HS) have higher OXPHOS and glycolysis than those from low scarrers, and demonstrated changes in mitochondrial function that suggest a higher energy state at baseline. Expression of PKM2, a key rate-limiting enzyme of aerobic glycolysis, was also higher in HS fibroblasts, with increased PKM2 phosphorylation/dimerization shunting metabolites toward increased ATP production and promoting aerobic glycolysis and pro-fibrotic pathways under TGF-β stimulation. HS fibroblasts also had an exaggerated response to mechanical tension, with an increase in total and phosphorylated PKM2. These data support the concept that PKM2-mediated aerobic glycolysis in fibroblasts under tension may influence the magnitude of fibrosis. Consistently, we also noted an exaggerated increase in phosphorylation of Hsp27 in HS fibroblast under tension. To our knowledge, this is the first evidence of differential aerobic glycolysis and biomechanical tension responses being linked to opposing scar outcomes in physiologic wounds, which could explain wound healing heterogeneity. We hypothesize that patient-specific scarring responses are due to PKM2/Hsp27-dependent alterations in fibroblast aerobic glycolysis that are influenced by wound biomechanical forces. In Aim 1, we designed in vitro and in vivo experiments with low and high scar-derived patient fibroblasts to investigate differences in PKM2 and Hsp27 phosphorylation/activation and their effect on metabolic pathways, energy metabolism, and ECM production. In Aim 2, we will utilize in vitro and human skin xenotransplant wound models to examine how biomechanical tension alters PKM2/Hsp27 mediated energy metabolism to drive patient scarring responses and then develop and validate a novel predictive model for individual scarring propensity (low or high) based on fibroblast bioenergetic signatures. This will lead to the development of anti-fibrotic therapies based on an individual’s metabolic profile, which could have implications for other fibrotic diseases.

项目概要皮肤损伤导致纤维化和疤痕形成，这可能是发病的重要来源。人类对相同的皮肤损伤有不同程度的疤痕形成反应，疤痕形成程度从低到高不等了解导致异质疤痕结果的机制将使我们能够。设计策略以引导伤口愈合再生并减少生物力学力。已知会影响皮肤愈合的生物力学张力信号，成纤维细胞增殖、迁移、这些反应与炎症功能和细胞外基质 (ECM) 的产生相结合。伤口中的氧化应激，对成纤维细胞的能量需求通常很高。细胞通过稳态条件下的线粒体氧化磷酸化（OXPHOS）或通过最近的研究表明，机械信号的增加可以改变能量。值得注意的是，代谢转向“有氧糖酵解”的现象。（瓦尔堡效应）主要描述了纤维化疾病的进展，但我们的数据表明，成纤维细胞来自具有高疤痕表型 (HS) 的健康患者的未受伤皮肤具有较高的 OXPHOS 和糖酵解与来自低疤痕的人相比，并表现出线粒体功能的变化，表明能量更高 HS 中有氧糖酵解的关键限速酶 PKM2 的表达也较高。成纤维细胞，PKM2 磷酸化/二聚化增加，将代谢物分流至增加的 ATP 在 TGF-β 刺激下，促进有氧糖酵解和促纤维化途径。对机械张力也有过度反应，总 PKM2 和磷酸化 PKM2 增加。这些数据支持这样的概念：张力下成纤维细胞中 PKM2 介导的有氧糖酵解可能一致地，我们还注意到磷酸化的过度增加。据我们所知，HS 成纤维细胞在张力下的 Hsp27 是差异有氧糖酵解的第一个证据。生物力学张力反应与生理伤口中相反的疤痕结果有关，我们勇敢地解释了愈合伤口的异质性是由于患者特异性的疤痕反应造成的。受伤口生物力学影响的成纤维细胞有氧糖酵解中 PKM2/Hsp27 依赖性改变在目标 1 中，我们设计了低度和高度疤痕来源的患者成纤维细胞的体外和体内实验。研究 PKM2 和 Hsp27 磷酸化/激活的差异及其对代谢途径的影响，在目标2中，我们将利用体外和人体皮肤异种移植伤口。研究生物力学张力如何改变 PKM2/Hsp27 介导的能量代谢以驱动患者的模型疤痕反应，然后开发和验证个体疤痕倾向的新预测模型（低或高）基于成纤维细胞生物能量特征这将导致抗纤维化的发展。基于个人代谢特征的疗法，这可能对其他纤维化疾病产生影响。