Defining the Cardiac Fibroblast Secretome in a Fibrotic Microenvironment.
Defining the Cardiac Fibroblast Secretome in a Fibrotic Microenvironment.
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DOI：
10.1161/jaha.120.017025
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发表时间：
2020-10-20
影响因子：
5.4
通讯作者：
Leinwand LA
中科院分区：
文献类型：
--
作者：
Ceccato TL;Starbuck RB;Hall JK;Walker CJ;Brown TE;Killgore JP;Anseth KS;Leinwand LA
心脏成纤维细胞（CF）具有感知僵硬度变化的能力，并对生化信号作出反应，以调节其作为静止或活化肌成纤维细胞的状态。考虑到生物活性分子分泌调节心脏微环境的潜力，我们试图确定CF分泌组如何随基质硬度和生化线索而变化，以及这如何通过旁分泌信号传导影响心肌细胞。通过使用工程化聚（乙二醇）水凝胶将刚度提示与TGFβ1（转化生长因子β 1）治疗相结合，在体外调节肌成纤维细胞活化，并在体内使用异丙肾上腺素治疗。僵硬、TGFβ1和异丙肾上腺素处理增加了AKT（蛋白激酶B）磷酸化，表明该途径可能是肌成纤维细胞活化的中心，无论处理如何。虽然AKT的激活是共享的，但不同的激活信号对下游细胞因子分泌具有不同的影响，表明并非所有激活的肌成纤维细胞共享相同的分泌组。为了测试CF分泌体中存在的细胞因子对旁分泌信号传导的影响，用CF条件培养基处理新生大鼠心室心肌细胞。在坚硬的基质上培养并由TGFβ1激活的肌成纤维细胞的条件培养基引起肥大，该培养基中的细胞因子之一是胰岛素生长因子1，其是心肌细胞肥大的已知介质。在坚硬的基质上培养CFs，用TGFβ1处理，和用异丙肾上腺素在体内处理都引起肌成纤维细胞活化。每种信号对分泌组或编码分泌组的基因有不同的影响，但只有在用TGFβ1处理的刚性基质上的活化肌成纤维细胞的分泌组引起肌细胞肥大，最有可能是通过胰岛素生长因子1。
Cardiac fibroblasts (CFs) have the ability to sense stiffness changes and respond to biochemical cues to modulate their states as either quiescent or activated myofibroblasts. Given the potential for secretion of bioactive molecules to modulate the cardiac microenvironment, we sought to determine how the CF secretome changes with matrix stiffness and biochemical cues and how this affects cardiac myocytes via paracrine signaling. Myofibroblast activation was modulated in vitro by combining stiffness cues with TGFβ1 (transforming growth factor β 1) treatment using engineered poly (ethylene glycol) hydrogels, and in vivo with isoproterenol treatment. Stiffness, TGFβ1, and isoproterenol treatment increased AKT (protein kinase B) phosphorylation, indicating that this pathway may be central to myofibroblast activation regardless of the treatment. Although activation of AKT was shared, different activating cues had distinct effects on downstream cytokine secretion, indicating that not all activated myofibroblasts share the same secretome. To test the effect of cytokines present in the CF secretome on paracrine signaling, neonatal rat ventricular cardiomyocytes were treated with CF conditioned media. Conditioned media from myofibroblasts cultured on stiff substrates and activated by TGFβ1 caused hypertrophy, and one of the cytokines in that media was insulin growth factor 1, which is a known mediator of cardiac myocyte hypertrophy. Culturing CFs on stiff substrates, treating with TGFβ1, and in vivo treatment with isoproterenol all caused myofibroblast activation. Each cue had distinct effects on the secretome or genes encoding the secretome, but only the secretome of activated myofibroblasts on stiff substrates treated with TGFβ1 caused myocyte hypertrophy, most likely through insulin growth factor 1.