From the Institute of Cardiology, The First Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, PR China.
Department of Ultrasound, The First Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, PR China.
Sci Rep. 2016 Dec 23;6:39186. doi: 10.1038/srep39186.
Farnesyl pyrophosphate synthase (FPPS) is a key enzyme in the mevalonate pathway. In our previous studies, we find that inhibition of FPPS attenuates angiotensin II-induced cardiac hypertrophy and fibrosis by suppressing RhoA while FPPS and Ras are up-regulated in pressure overload rats. In this study, we evaluate the effects and mechanisms of FPPS inhibition in pressure overload mice. Male FPPS-small interfering RNA (SiRNA) transgenic (Tg) mice and non-transgenic littermate control (NLC) were randomly divided into suprarenal abdominal aortic constriction (AAC) group and sham operation group. 12 weeks following AAC, mice were sacrificed by cervical dislocation. Histological and echocardiographic assessments showed that inhibition of FPPS improved chronic cardiac remodeling which was induced by AAC. The reductions of Ras farnesylation and GTP-Ras, as well as their downstream extracellular signal-related kinases 1/2 (ERK1/2) expression were observed in the heart of Tg-AAC mice compared with NLC-AAC mice, along with the reduction of fetal gene expression. We provide here important experimental evidence that inhibition of FPPS improves AAC induced chronic cardiac remodeling and fibrosis by the reduction of farnesylated Ras and the downregulation of Ras-ERK1/2 pathway.
法呢基焦磷酸合酶(FPPS)是甲羟戊酸途径中的关键酶。在我们之前的研究中,发现抑制 FPPS 通过抑制 RhoA 可减轻血管紧张素 II 诱导的心肌肥大和纤维化,而 FPPS 和 Ras 在压力超负荷大鼠中上调。在这项研究中,我们评估了 FPPS 抑制在压力超负荷小鼠中的作用和机制。雄性 FPPS-小干扰 RNA(siRNA)转基因(Tg)小鼠和非转基因同窝对照(NLC)随机分为肾上腹主动脉缩窄(AAC)组和假手术组。AAC 后 12 周,通过颈椎脱位处死小鼠。组织学和超声心动图评估显示,抑制 FPPS 改善了 AAC 诱导的慢性心脏重构。与 NLC-AAC 小鼠相比,Tg-AAC 小鼠心脏中 Ras 法尼基化和 GTP-Ras 减少,以及下游细胞外信号相关激酶 1/2(ERK1/2)表达减少,同时胎儿基因表达减少。我们在这里提供了重要的实验证据,表明抑制 FPPS 通过减少法尼基化 Ras 和下调 Ras-ERK1/2 通路,改善 AAC 诱导的慢性心脏重构和纤维化。