Department of Cardiology and Hematology, Fukushima Medical University, Fukushima, Japan.
Biochem Biophys Res Commun. 2013 Sep 13;439(1):142-7. doi: 10.1016/j.bbrc.2013.08.002. Epub 2013 Aug 9.
Senescence marker protein 30 (SMP30) is assumed to behave as an anti-aging factor. Recently, we have demonstrated that deficiency of SMP30 exacerbates angiotensin II-induced cardiac hypertrophy, dysfunction and remodeling, suggesting that SMP30 may have a protective role in the heart. Thus, this study aimed to test the hypothesis that up-regulation of SMP30 inhibits cardiac adverse remodeling in response to angiotensin II.
We generated transgenic mice with cardiac-specific overexpression of SMP30 gene using α-myosin heavy chain promoter. Transgenic mice and wild-type littermate mice were subjected to continuous angiotensin II infusion (800 ng/kg/min).
After 14 days, heart weight and left ventricular weight were lower in transgenic mice than in wild-type mice, although blood pressure was similarly elevated during angiotensin II infusion. Cardiac hypertrophy and diastolic dysfunction in response to angiotensin II were prevented in transgenic mice compared with wild-type mice. The degree of cardiac fibrosis by angiotensin II was lower in transgenic mice than in wild-type mice. Angiotensin II-induced generation of superoxide and subsequent cellular senescence were attenuated in transgenic mouse hearts compared with wild-type mice.
Cardiac-specific overexpression of SMP30 inhibited angiotensin II-induced cardiac adverse remodeling. SMP30 has a cardio-protective role with anti-oxidative and anti-aging effects and could be a novel therapeutic target to prevent cardiac hypertrophy and remodeling due to hypertension.
衰老标志物蛋白 30(SMP30)被认为是一种抗衰老因子。最近,我们已经证明 SMP30 的缺乏会加剧血管紧张素 II 诱导的心脏肥大、功能障碍和重构,这表明 SMP30 可能在心脏中具有保护作用。因此,本研究旨在验证 SMP30 的上调抑制血管紧张素 II 引起的心脏不良重构的假设。
我们使用α-肌球蛋白重链启动子在心脏特异性过表达 SMP30 基因的转基因小鼠中生成。转基因小鼠和野生型同窝小鼠接受持续的血管紧张素 II 输注(800ng/kg/min)。
14 天后,尽管在血管紧张素 II 输注期间血压相似升高,但转基因小鼠的心脏重量和左心室重量低于野生型小鼠。与野生型小鼠相比,转基因小鼠对血管紧张素 II 的心脏肥大和舒张功能障碍得到了预防。转基因小鼠的心脏纤维化程度低于野生型小鼠。与野生型小鼠相比,转基因小鼠心脏中血管紧张素 II 诱导的超氧化物生成和随后的细胞衰老减少。
心脏特异性过表达 SMP30 抑制了血管紧张素 II 诱导的心脏不良重构。SMP30 具有抗氧化和抗衰老作用的心脏保护作用,可能是预防高血压引起的心脏肥大和重构的新型治疗靶点。