抑制线粒体磷酸盐载体可防止高磷酸盐诱导的超氧化物生成和血管钙化。
Inhibition of mitochondrial phosphate carrier prevents high phosphate-induced superoxide generation and vascular calcification.
机构信息
Department of Physiology, Yonsei University Wonju College of Medicine, Wonju, Korea.
Mitohormesis Research Center, Yonsei University Wonju College of Medicine, Wonju, Korea.
出版信息
Exp Mol Med. 2023 Mar;55(3):532-540. doi: 10.1038/s12276-023-00950-0. Epub 2023 Mar 1.
Vascular calcification is a serious complication of hyperphosphatemia that causes cardiovascular morbidity and mortality. Previous studies have reported that plasmalemmal phosphate (Pi) transporters, such as PiT-1/2, mediate depolarization, Ca influx, oxidative stress, and calcific changes in vascular smooth muscle cells (VSMCs). However, the pathogenic mechanism of mitochondrial Pi uptake in vascular calcification associated with hyperphosphatemia has not been elucidated. We demonstrated that the phosphate carrier (PiC) is the dominant mitochondrial Pi transporter responsible for high Pi-induced superoxide generation, osteogenic gene upregulation, and calcific changes in primary VSMCs isolated from rat aortas. Notably, acute incubation with high Pi markedly increased the protein abundance of PiC via ERK1/2- and mTOR-dependent translational upregulation. Genetic suppression of PiC prevented Pi-induced ERK1/2 activation, superoxide production, osteogenic differentiation, and vascular calcification of VSMCs in vitro and aortic rings ex vivo. Pharmacological inhibition of mitochondrial Pi transport using butyl malonate (BMA) or mersalyl abolished all pathologic changes involved in high Pi-induced vascular calcification. BMA or mersalyl also effectively prevented osteogenic gene upregulation and calcification of aortas from 5/6 subtotal nephrectomized mice fed a high-Pi diet. Our results suggest that mitochondrial Pi uptake via PiC is a critical molecular mechanism mediating mitochondrial superoxide generation and pathogenic calcific changes, which could be a novel therapeutic target for treating vascular calcification associated with hyperphosphatemia.
血管钙化是高磷血症的严重并发症,可导致心血管发病率和死亡率增加。先前的研究报告称,质膜磷酸盐(Pi)转运体,如 PiT-1/2,介导血管平滑肌细胞(VSMCs)去极化、Ca2+内流、氧化应激和钙化变化。然而,与高磷血症相关的血管钙化中线粒体 Pi 摄取的致病机制尚未阐明。我们证明,磷酸载体(PiC)是主要的线粒体 Pi 转运体,负责高 Pi 诱导的超氧生成、成骨基因上调和大鼠主动脉分离的原代 VSMCs 的钙化变化。值得注意的是,急性高 Pi 孵育通过 ERK1/2 和 mTOR 依赖性翻译上调显著增加 PiC 的蛋白丰度。PiC 的基因抑制可防止 Pi 诱导的 ERK1/2 激活、超氧生成、成骨分化和 VSMCs 的血管钙化,以及体外主动脉环。使用丁基丙二酸(BMA)或 mersalyl 抑制线粒体 Pi 转运可消除高 Pi 诱导的血管钙化中涉及的所有病理变化。BMA 或 mersalyl 还可有效预防高磷饮食喂养的 5/6 肾部分切除小鼠主动脉中成骨基因上调和钙化。我们的研究结果表明,通过 PiC 摄取线粒体 Pi 是介导线粒体超氧生成和致病钙化变化的关键分子机制,这可能成为治疗与高磷血症相关的血管钙化的新治疗靶点。