Epigenetic modification of intestinal smooth muscle cell phenotype during proliferation
Epigenetic modification of intestinal smooth muscle cell phenotype during proliferation
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DOI：
10.1152/ajpcell.00216.2018
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发表时间：
2018-11-01
影响因子：
5.5
通讯作者：
Blennerhassett, Michael G.
中科院分区：
文献类型：
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作者：
Bonafiglia, Quinn A.;Lourenssen, Sandra R.;Blennerhassett, Michael G.
炎症引起肠平滑肌细胞（ISMC）增殖，导致克罗恩病中肠壁增厚和狭窄形成。ISMC在体外和体内的增殖导致标志蛋白的表达降低，但其根本原因尚不清楚。由于表观遗传变化在其他系统中很重要，我们使用免疫细胞化学，免疫印迹和定量PCR来检查大鼠结肠细胞系在低传代或延长生长后的表观遗传修饰，以评估表型。暴露于组蛋白去乙酰化酶（HDAC）抑制剂阿司他丁A或DNA甲基转移酶抑制剂5-氮杂胞苷逆转了ISMC高传代细胞系中表型标记的特征性丢失。平滑肌肌动蛋白和平滑肌蛋白22的表达，以及神经营养因子胶质细胞系衍生的神经营养因子的功能表达，显着增加。毒蕈碱受体3和肌球蛋白轻链激酶的表达增加与胆碱能刺激的反应上调相关。在来自回肠末端的人ISMC（hISMC）系中，表型受到扩展增殖的类似影响。然而，在从切除的克罗恩氏狭窄的hISMC中，我们观察到与患者匹配的内在对照相比显著降低的收缩表型，其与DNA甲基转移酶1、HDAC 2和HDAC 5的增加的患者特异性表达相关。因此，延长的生长引起表观遗传改变，其解释了ISMC的改变的表型。类似的过程可能会促进克罗恩病的狭窄形成，其中通过控制表型调节来阻止疾病进展甚至逆转的可能性可能成为一种新的治疗选择。
Inflammation causes proliferation of intestinal smooth muscle cells (ISMC), contributing to a thickened intestinal wall and to stricture formation in Crohn's disease. Proliferation of ISMC in vitro and in vivo caused decreased expression of marker proteins, but the underlying cause is unclear. Since epigenetic change is important in other systems, we used immunocytochemistry, immunoblotting, and quantitative PCR to examine epigenetic modification in cell lines from rat colon at low passage or after extended growth to evaluate phenotype. Exposure to the histone deacetylase (HDAC) inhibitor trichostatin A or the DNA methyltransferase inhibitor 5-azacytidine reversed the characteristic loss of phenotypic markers among high-passage cell lines of ISMC. Expression of smooth muscle actin and smooth muscle protein 22, as well as functional expression of the neurotrophin glial cell line-derived neurotrophic factor, was markedly increased. Increased expression of muscarinic receptor 3 and myosin light chain kinase was correlated with an upregulated response to cholinergic stimulation. In human ISMC (hISMC) lines from the terminal ileum, phenotype was similarly affected by extended proliferation. However, in hISMC from resected Crohn's strictures, we observed a significantly reduced contractile phenotype compared with patient-matched intrinsic controls that was associated with increased patient-specific expression of DNA methyltransferase 1, HDAC2, and HDAC5. Therefore, protracted growth causes epigenetic alterations that account for an altered phenotype of ISMC. A similar process may promote stricture formation in Crohn's disease, where the potential for halting progression, or even reversal, of disease through control of phenotypic modulation may become a novel treatment option.