Salerno Alessandro G, Wanschel Amarylis C B A, Dulce Raul A, Hatzistergos Konstantinos E, Balkan Wayne, Hare Joshua M
Department of Medicine and Interdisciplinary Stem Cell Institute, University of Miami Miller School of Medicine, Miami, FL 33136, USA.
J Cardiovasc Aging. 2021;1. doi: 10.20517/jca.2021.19. Epub 2021 Sep 7.
Induced pluripotent stem cells (iPSCs) provide a model of cardiomyocyte (CM) maturation. Nitric oxide signaling promotes CM differentiation and maturation, although the mechanisms remain controversial.
The study tested the hypothesis that in the absence of S-nitrosoglutathione reductase (GSNOR), a denitrosylase regulating protein S-nitrosylation, the resultant increased S-nitrosylation accelerates the differentiation and maturation of iPSC-derived cardiomyocytes (CMs).
iPSCs derived from mice lacking GSNOR (iPSC) matured faster than wildtype iPSCs (iPSC) and demonstrated transient increases in expression of murine Snail Family Transcriptional Repressor 1 gene (), murine Snail Family Transcriptional Repressor 2 gene () and murine Twist Family BHLH Transcription Factor 1 gene (), transcription factors that promote epithelial-to-mesenchymal transition (EMT) and that are regulated by Glycogen Synthase Kinase 3 Beta (GSK3β). Murine Glycogen Synthase Kinase 3 Beta () gene exhibited much greater S-nitrosylation, but lower expression in iPSC. S-nitrosoglutathione (GSNO)-treated iPSC and human (h)iPSCs also demonstrated reduced expression of GSK3β. expression, a CM marker, was increased in iPSC upon directed differentiation toward CMs on Day 4, whereas murine Brachyury (), , and GATA Binding Protein () mRNA were decreased, compared to iPSC, suggesting that GSNOR deficiency promotes CM differentiation beginning immediately following cell adherence to the culture dish-transitioning from mesoderm to cardiac progenitor.
Together these findings suggest that increased S-nitrosylation of Gsk3β promotes CM differentiation and maturation from iPSCs. Manipulating the post-translational modification of GSK3β may provide an important translational target and offers new insight into understanding of CM differentiation from pluripotent stem cells.
Deficiency of GSNOR or addition of GSNO accelerates early differentiation and maturation of iPSC-cardiomyocytes.
诱导多能干细胞（iPSC）为心肌细胞（CM）成熟提供了一个模型。一氧化氮信号传导促进CM分化和成熟，但其机制仍存在争议。
本研究检验了以下假设：在缺乏S-亚硝基谷胱甘肽还原酶（GSNOR，一种调节蛋白质S-亚硝基化的去亚硝基化酶）的情况下，由此导致的S-亚硝基化增加会加速iPSC衍生的心肌细胞（CM）的分化和成熟。
缺乏GSNOR的小鼠来源的iPSC（iPSC）比野生型iPSC（iPSC）成熟得更快，并表现出小鼠Snail家族转录抑制因子1基因（）、小鼠Snail家族转录抑制因子2基因（）和小鼠Twist家族BHLH转录因子1基因（）表达的短暂增加，这些转录因子促进上皮-间质转化（EMT）并受糖原合酶激酶3β（GSK3β）调节。小鼠糖原合酶激酶3β（）基因表现出更高的S-亚硝基化，但在iPSC中的表达较低。用S-亚硝基谷胱甘肽（GSNO）处理的iPSC和人（h）iPSC也表现出GSK3β表达降低。在第4天定向分化为CM时，iPSC中CM标志物的表达增加，而与iPSC相比，小鼠短尾（）、和GATA结合蛋白（）mRNA减少，这表明GSNOR缺乏促进CM分化，在细胞贴壁到培养皿后立即开始，即从中胚层向心脏祖细胞转变。
这些发现共同表明，Gsk3β的S-亚硝基化增加促进了iPSC的CM分化和成熟。操纵GSK3β的翻译后修饰可能提供一个重要的转化靶点，并为理解多能干细胞的CM分化提供新见解。
GSNOR缺乏或添加GSNO可加速iPSC-心肌细胞的早期分化和成熟。
