Downregulation of microRNA-29 by antisense inhibitors and a PPAR-γ agonist protects against myocardial ischaemia-reperfusion injury
Downregulation of microRNA-29 by antisense inhibitors and a PPAR-γ agonist protects against myocardial ischaemia-reperfusion injury
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DOI：
10.1093/cvr/cvq053
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发表时间：
2010-08-01
影响因子：
10.8
通讯作者：
Perez-Polo, Jose R.
中科院分区：
文献类型：
--
作者：
Ye, Yumei;Hu, Zhaoyong;Perez-Polo, Jose R.
MicroRNAs(MiRNAs)调控多种心脏过程，包括细胞增殖和凋亡。吡格列酮(PIO)是一种过氧化物酶体增殖物激活受体(PPAR)-γ激动剂，对心肌缺血再灌注(IR)损伤具有保护作用。我们评估了PPAR-γ激活对心肌miRNA水平的影响以及miRNAs在IR损伤中的作用。我们利用miRNA阵列评估了PIO给药后大鼠心脏miRNAs表达的变化，并通过Northern印迹证实了这一结果。PIO治疗7d后，miR-29a和miR-29c水平明显下降。在H9c2细胞中，PIO和罗格列酮对miR-29表达水平的影响可被选择性PPAR-γ抑制剂GW9662阻断。反义抑制剂或PIO下调miR-29可保护H9c2细胞免受模拟IR损伤，表现为细胞存活率增加，caspase-3活性降低。相反，过表达miR-29促进细胞凋亡，并完全阻断PIO的保护作用。抗miR-29a或miR-29c的拮抗剂可显著减少IR损伤后的心肌梗死面积和细胞凋亡。Western印迹分析表明，抑制miR-29可增加抗细胞凋亡的Bcl2家族成员Mcl-2的表达，下调miR-29对IR损伤的保护作用。MiRNAs的调控可以通过药物干预来实现。这些发现为开发基于miRNA的减轻IR损伤的策略提供了理论基础。
MicroRNAs (miRNAs) regulate various cardiac processes including cell proliferation and apoptosis. Pioglitazone (PIO), a peroxisome proliferator-activated receptor (PPAR)-gamma agonist, protects against myocardial ischaemia-reperfusion (IR) injury. We assessed the effects of PPAR-gamma activation on myocardial miRNA levels and the role of miRNAs in IR injury.We evaluated the expression changes of miRNAs in the rat heart after PIO administration using miRNA arrays and then confirmed the result by northern blot. miR-29a and c levels decreased remarkably after 7-day treatment with PIO. In H9c2 cells, the effects of PIO and rosiglitazone on miR-29 expression levels were blocked by a selective PPAR-gamma inhibitor GW9662. Downregulation of miR-29 by antisense inhibitor or by PIO protected H9c2 cells from simulated IR injury, indicated as increased cell survival and decreased caspase-3 activity. In contrast, overexpressing miR-29 promoted apoptosis and completely blocked the protective effect of PIO. Antagomirs against miR-29a or -29c significantly reduced myocardial infarct size and apoptosis in hearts subjected to IR injury. Western blot analyses demonstrated that Mcl-2, an anti-apoptotic Bcl-2 family member, was increased by miR-29 inhibition.Downregulation of miR-29 protected hearts against IR injury. The modulation of miRNAs can be achieved by pharmacological intervention. These findings provide a rationale for the development of miRNA-based strategies for the attenuation of IR injury.