肌成纖維細胞來源的外泌體引起心臟內皮細胞功能障礙
貴州醫科大學 高鴻教授課題組
翻譯：周菁 編輯：佟睿 審校：曹瑩
內皮細胞（ECS）在維持血管穩態和心臟功能方面發揮著關鍵作用。結果表明，活化的成纖維細胞衍生的外泌體損害肥厚性心臟心肌細胞功能，但它們對ECS的影響尚不清楚。因此，我們假設激活的心肌成纖維細胞衍生的外泌體（FB-EXO）介導EC功能障礙，因此調節心肌成纖維細胞外泌體含量可以改善內皮功能。
從心肌成纖維細胞（FB） - 調節劑中分離出外泌體，并通過納米顆粒跟蹤分析和電子顯微鏡表征。從小鼠心臟中分離出內皮細胞。用從FB為條件的培養液中分離的外泌體處理內皮細胞，再用轉化生長因子-β1(TGF-β1-FB-Exo)或磷酸鹽(對照組)處理FB。血管內皮細胞功能受損(表現為血管內皮生長因子-A、HIF-1α、CD31和血管生成素1基因表達降低，管狀形成和細胞遷移減少)。β-FB-Exo處理的細胞表現為血管內皮細胞功能減退(表現為血管內皮生長因子-A、HIF1mRNA、CD31mRNA和血管生成素1基因表達降低)。此外，轉化生長因子-β1-FB-Exo處理的內皮細胞與對照組相比，細胞增殖減少，凋亡增加。轉化生長因子受體-β1-FB-Exo Cargo分析顯示纖維化相關miRNA發生改變，包括miR-200A-3p水平顯著升高。有趣的是，miR-200A-3p抑制活化的FBS，減輕轉化生長因子-β1-FB-Exo介導的內皮功能障礙。
綜上所述，本研究證實了激活的成纖維細胞來源的外泌體中富集的miR-200a-3p對內皮細胞生物學和功能的重要作用。
Ranjan P, Kumari R, Goswami SK, et al，Myofibroblast-Derived Exosome Induce Cardiac Endothelial Cell Dysfunction.Front Cardiovasc Med 2021;8
Myofibroblast-Derived Exosome Induce Cardiac Endothelial Cell Dysfunction.
Background: Endothelial cells (ECs) play a critical role in the maintenance of vascular homeostasis and in heart function. It was shown that activated fibroblast-derived
exosomes impair cardiomyocyte function in hypertrophic heart, but their effect on ECs is not yet clear. Thus, we hypothesized that activated cardiac fibroblast-derived exosomes(FB-Exo) mediate EC dysfunction, and therefore modulation of FB-exosomal contents may improve endothelial function.
Methods and Results: Exosomes were isolated from cardiac fibroblast (FB)-conditioned media and characterized by nanoparticle tracking analysis and electron microscopy. ECs were isolated from mouse heart. ECs were treated with exosomes isolated from FB-conditioned media, following FB culture with TGF-β1 (TGF-β1-FB-Exo) or PBS (control) treatment. TGF-β1 significantly activated fibroblasts as shown by increase in collagen type1 α1 (COL1α1), periostin (POSTN), and fibronectin (FN1) gene expression and increase in Smad2/3 and p38 phosphorylation. Impaired endothelial cell function (as characterized by a decrease in tube formation and cell migration along with reduced VEGF-A, Hif1α, CD31, and angiopoietin1 gene expression) was observed in TGF-β1-FB-Exo treated cells. Furthermore, TGF-β1-FB-Exo treated ECs showed reduced cell proliferation and increased apoptosis as compared to control cells. TGF-β1-FB-Exo cargo analysis revealed an alteration in fibrosis-associated miRNAs, including a significant increase in miR-200a-3p level. Interestingly, miR-200a-3p inhibition in activated FBs, alleviated TGF-β1-FB-Exo-mediated endothelial dysfunction.
Conclusions: Taken together, this study demonstrates an important role of miR-200a-3p enriched within activated fibroblast-derived exosomes on endothelial cell biology and function.
