Identification and its functional analysis of ion channels involving in pathophysiologic remodeling of vascular smooth muscle

血管平滑肌病理生理重塑离子通道的鉴定及其功能分析

• 批准号: 20590814
• 负责人: NAKAJIMA Toshiaki
• 金额: $ 3万
• 依托单位: The University of Tokyo
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (C)
• 财政年份: 2008
• 资助国家: 日本
• 起止时间: 2008 至 2010
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-20590814/
• 关键词: vascular smooth muscle; voltage-gated Na channel; migration; proliferation; patch-clamp; balloon injury; coronary smooth muscle; Ca channel; Vascular smooth muscle; Patch-clamp; Ion channel; TRP; Pura-2; Coronary smooth muscle; Voltage-gated

Voltage-gated Na^+ channel currents (I(Na)) are expressed in several types of smooth muscle cells. We evaluated the expression of I(Na), its functional role, pathophysiology in cultured human (hASMCs) and rabbit aortic smooth muscle cells (rASMCs), and its association with vascular intimal hyperplasia. In whole cell voltage clamp, I(Na) was observed at potential positive to -40 mV, was blocked by tetrodotoxin (TTX), and replacing extracellular Na+ with N-methyl-d-glucamine in cultured hASMCs. In contrast to native aorta, cultured hASMCs strongly expressed SCN9A encoding Na(V)1.7, as determined by quantitative RT-PCR. I(Na) was abolished by the treatment with SCN9A small-interfering (si)RNA (P<0.01). TTX and SCN9A siRNA significantly inhibited cell migration (P<0.01, respectively) and horseradish peroxidase uptake (P<0.01, respectively). TTX also significantly reduced the secretion of matrix metalloproteinase-2 6 and 12 h after the treatment (P<0.01 and P<0.05, respectively). However, n … More either TTX nor siRNA had any effect on cell proliferation. L-type Ca^<2+> channel current was recorded, and I(Na) was not observed in freshly isolated rASMCs, whereas TTX-sensitive I(Na) was recorded in cultured rASMCs. Quantitative RT-PCR and immunostaining for Na(V)1.7 revealed the prominent expression of SCN9A in cultured rASMCs and aorta 48 h after balloon injury but not in native aorta. These studies showed that I(Na) is expressed in cultured and diseased conditions but not in normal aorta. The Na(V)1.7 plays an important role in cell migration, endocytosis, and secretion. Na(V)1.7 is also expressed in aorta after balloon injury, suggesting a potential role for Na(V)1.7 in the progression of intimal hyperplasia. In addition, serum amyloid A (SAA), an acute-phase protein, and lysophosphatidylcholine (LPC), an oxidized LDL component, contribute to physiological processes of atherosclerosis and cardiovascular disease. However, the effects of SAA/LPC on human coronary artery smooth muscle cells (hCASMCs) have not been fully investigated. Therefore, I examined the effects of SAA/LPC on Ca^<2+>/Mg^<2+> mobilization and its underlying mechanisms in hCASMCs. We showed that SAA/LPC activate Ca^<2+> influx in hCASMCs; SAA activates it via PTX-sensitive G-protein, PLC and TRPC pathways, where TRPC4 may be involved. On the other hand, LPC may activate it via TRPM7 independently of these pathways. Thus, TRP protein appears to be a target molecule of Ca^<2+> signaling in hCASMCs elicited by SAA/LPC, which may play roles in coronary muscle dysfunction under the pathophysiological and inflammatory conditions such as atherosclerosis. These results provide a possibility of ion channel blockers as a therapy for atherosclerotic diseases such as coronary artery diseases. Less

电压门控Na^+通道电流（I（Na））在几种类型的平滑肌细胞中表达。我们评估了I（Na）的表达，其功能作用，在培养的人（hASMCs）和兔主动脉平滑肌细胞（rASMCs）的病理生理学，及其与血管内膜增生的关系。在全细胞电压钳技术中，I（Na）在-40 mV电位下可被河豚毒素（TTX）阻断，并可被N-甲基-D-葡糖胺（N-methyl-d-glucamine）替代。与天然主动脉相反，培养的hASMCs强烈表达编码Na（V）1.7的SCN 9A，如通过定量RT-PCR测定的。用SCN 9A小干扰RNA处理后，I（Na）明显降低（P<0.01）。TTX和SCN 9A siRNA显著抑制细胞迁移（P<0.01）和辣根过氧化物酶摄取（P<0.01）。TTX治疗后6 h和12 h也能显著降低MMP-2的分泌（P<0.01和P<0.05）。然而，n ...更多信息 TTX和siRNA对细胞增殖均无影响。在新鲜分离的rASMCs中记录到L型Ca^<2+>通道电流，未观察到I（Na），而在培养的rASMCs中记录到TTX敏感的I（Na）。定量RT-PCR和Na（V）1.7免疫组化染色显示，在球囊损伤后48 h，SCN 9A在培养的rASMCs和主动脉中显著表达，而在自体主动脉中无表达。这些研究表明，I（Na）在培养和患病条件下表达，但在正常主动脉中不表达。Na（V）1.7在细胞迁移、内吞和分泌中起重要作用。Na（V）1.7也在球囊损伤后的主动脉中表达，表明Na（V）1.7在内膜增生的进展中的潜在作用。此外，血清淀粉样蛋白A（SAA），一种急性时相蛋白，和溶血磷脂酰胆碱（LPC），一种氧化的LDL成分，有助于动脉粥样硬化和心血管疾病的生理过程。然而，SAA/LPC对人冠状动脉平滑肌细胞（hCASMCs）的影响尚未得到充分研究。因此，我研究了SAA/LPC对hCASMC中Ca^2+/Mg^2+动员的影响及其潜在机制。我们发现SAA/LPC可激活hCASMC中的Ca^2+内流; SAA通过PTX敏感的G蛋白、PLC和TRPC途径激活Ca ^2+内流，其中TRPC 4可能参与其中。另一方面，LPC可以独立于这些途径通过TRPM 7激活它。因此，TRP蛋白可能是SAA/LPC介导的hCASMCs Ca ^2+信号转导的靶分子，在动脉粥样硬化等病理生理和炎症状态下的冠状肌功能障碍中发挥作用。这些结果为离子通道阻滞剂作为冠状动脉疾病等动脉粥样硬化性疾病的治疗提供了可能性。少

项目成果

Low-intensity resistance exercise with blood flow restriction does not activate coagulation system in young men

限制血流的低强度阻力运动不会激活年轻男性的凝血系统

• 发表时间: 2010
• 作者: Madarame H;Kurano M;Takano H;Iida H;Sato Y;Ohshima H;Abe T;Ishii N;Morita T;Nakajima T.
• 通讯作者: Nakajima T.

Direct action of an angiotensin II receptor blocker on angiotensin II-induced left atrial conduction delay in spontaneously hypertensive rats

• DOI: 10.1038/hr.2009.89
• 发表时间: 2009-08-01
• 期刊: HYPERTENSION RESEARCH
• 影响因子: 5.4
• 作者: Matsuyama, Narihisa;Tsutsumi, Takeshi;Takeyama, Youici
• 通讯作者: Takeyama, Youici

大動脈平滑筋細胞に発現する電位依存性ナトリウムチャネル(Na_v1.7)の機能とその役割

主动脉平滑肌细胞表达的电压门控钠通道（Na_v1.7）的功能和作用

• 发表时间: 2007
• 作者: 目黒健太郎;佐田政隆;永井良三;中島敏明
• 通讯作者: 中島敏明

Effect of dexamethasone on voltage-gated Nal+ channel in cultured human bronchial smooth muscle cells

地塞米松对培养人支气管平滑肌细胞电压门控Nal通道的影响

• 发表时间: 2008
• 期刊: Life Sci 82
• 作者: Nakajima T. Jo T. Meguro Oonuma H. Ma J. Kubota N;Imuta H;Takano H. Iida H;Nagase T;Nagata T.
• 通讯作者: Nagata T.

Effects of serum amyloid a and lysophosphatidylcholine on intracellular calcium concentration in human coronary artery smooth muscle cells.

• DOI: 10.1536/ihj.52.185
• 发表时间: 2011
• 期刊: International heart journal
• 影响因子: 1.5
• 作者: Tomofumi Tanaka;Ken'ichi Ikeda;Yumiko Yamamoto;H. Iida;Hironobu Kikuchi;T. Morita;T. Yamasoba;R. Nagai;T. Nakajima