Division of Cardiology, Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, MD, 21205, USA.
Basic Res Cardiol. 2012 Mar;107(2):248. doi: 10.1007/s00395-012-0248-6. Epub 2012 Feb 2.
The inflammatory cytokines interleukin (IL)-10 and tumor necrosis factor (TNF)-α play an important role in left ventricular (LV) remodeling after myocardial infarction (MI). Phosphatase and tensin homolog deleted on chromosome ten (PTEN) inactivates protein kinase Akt and promotes cell death in the heart. However, it is not known whether PTEN promotes post-MI remodeling by regulating IL-10 and TNF-α. MI was induced in wild-type (WT) mice and Pten heterozygous mutant (HET) mice. Pten adenoviruses (adPten) or empty vectors (adNull) were injected into the peri-infarct area of WT mice. LV dilation was attenuated and fractional shortening was increased in HET mice compared to WT mice. Survival rate and fractional shortening were decreased in adPten mice compared to adNull mice. Leukocyte infiltration into the peri-infarct area was attenuated in HET mice and worsened in adPten mice. PTEN expression was upregulated in the infarcted heart of WT mice. Partial inactivation of PTEN increased the production of IL-10 and decreased the expression of TNF-α and matrix metalloproteinase (MMP)-2 and -9 after MI in HET mice. PTEN overexpression caused opposite effects in the infarcted heart. Moreover in the infarcted heart of HET mice, Akt inhibition decreased Stat3 phosphorylation and IL-10 expression, and blockade of the IL-10 receptor increased TNF-α and MMP-2 expression. Both Akt inhibition and IL-10 receptor blockade abolished the attenuation of post-MI remodeling in HET mice. In conclusion, PTEN is critically involved in post-MI remodeling through the Akt/IL-10 signaling pathway. Therefore, targeting PTEN may be an effective approach to post-MI remodeling.
炎症细胞因子白细胞介素(IL)-10 和肿瘤坏死因子(TNF)-α 在心肌梗死后左心室(LV)重构中发挥重要作用。磷酸酶和张力蛋白同源物缺失的染色体 ten(PTEN)失活蛋白激酶 Akt 并促进心脏细胞死亡。然而,尚不清楚 PTEN 是否通过调节 IL-10 和 TNF-α 来促进心肌梗死后的重构。在野生型(WT)小鼠和 Pten 杂合突变(HET)小鼠中诱导心肌梗死。将 Pten 腺病毒(adPten)或空载体(adNull)注射到 WT 小鼠的梗死周围区域。与 WT 小鼠相比,HET 小鼠的 LV 扩张减弱,缩短分数增加。与 adNull 小鼠相比,adPten 小鼠的存活率和缩短分数降低。白细胞浸润到梗死周围区域在 HET 小鼠中减弱,在 adPten 小鼠中恶化。PTEN 表达在 WT 小鼠的梗死心脏中上调。PTEN 的部分失活增加了 HET 小鼠心肌梗死后 IL-10 的产生,降低了 TNF-α 和基质金属蛋白酶(MMP)-2 和 -9 的表达。PTEN 过表达在梗死心脏中引起相反的效果。此外,在 HET 小鼠的梗死心脏中,Akt 抑制降低了 Stat3 磷酸化和 IL-10 表达,阻断 IL-10 受体增加了 TNF-α 和 MMP-2 表达。Akt 抑制和 IL-10 受体阻断均消除了 HET 小鼠心肌梗死后重构的减弱。总之,PTEN 通过 Akt/IL-10 信号通路在心肌梗死后重构中起关键作用。因此,靶向 PTEN 可能是治疗心肌梗死后重构的有效方法。