Functional significance of nuclear diacylglycerol kinase in neurons and cardioocytes under ischemic stress

缺血应激下核二酰甘油激酶在神经元和心肌细胞中的功能意义

• 批准号: 18590179
• 负责人: GOTO Kaoru
• 金额: $ 2.57万
• 依托单位: Yamagata University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (C)
• 财政年份: 2006
• 资助国家: 日本
• 起止时间: 2006 至 2007
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-18590179/
• 关键词: ischemic stress; cardiomyocyte; neuron; lipid metabolism; nucleus

Diacylglycerol kinase (DGK) is an enzyme that phosphorylates a second messenger diacylglycerol (DG) and is involved in a variety of pathophysiological cellular responses. We have previously reported that DGKζ, characterized by a nuclear localization signal (NLS), is translocated from the nucleus to the cytoplasm in hippocampal pyramidal neurons after 20 min of transient forebrain ischemia. However, the detailed mechanism of this phenomenon and it's functional significance remains unknown.First, we used hippocampal slices exposed to oxygen and glucose deprivation (OGD) to simulate an ischemic model of the brain and evaluated the time course of the translocation of DGKζ. As seen in the animal ischemic model, DGKζ-immunoreactivity was gradually shifted from the nucleus to the cytoplasm after 20 min of OGD and was never detected in the nucleus after reperfusion. In addition, we found that while DGKζ was detected in the nucleus by 10 min of OGD, the following 60 min of reperfusion induced c … More omplete translocation of DGKζ from the nucleus to the cytoplasm. These results suggest that 10 min of OGD switches on the signal cascade to cause translocation of DGKζ to the cytoplasm.Second, we aimed to see whether the subcellular localization of DGKζ would change after the ischemic insult in cardiomyocytes, which are also postmitotic, highly differentiated cells after birth as neurons. We first generated the 10 min-transient ischemic heart model of rat by clipping of left anterior descending branch. In the non-ischemic septal region, DGKζ-immunoreactivity was observed in the nucleus of cardiomyocytes similarly to normal conditions. However, we found that the immunoreactivity almost disappeared from the nucleus of cardiomyocytes in the ischemic region. In the border area of the ischemic region, DGKζ-immunoreactivity was observed mostly in the nucleus and faintly in the cytoplasm. To examine the extent of the severity of ischemia to cause this change in subcellular localization of DGKζ, we generated models of 3 min-, 5 min-, and 20 min-ischemia. Surprisingly, 3 min of ischemia was shown to be enough to cause DGKζ to disappear from the nucleus in cardiomyocytes. Similar results were obtained from the 5 min- and 20 min-ischemic models. Collectively, under ischemic conditions of heart DGKζ quickly disappeared from the nucleus of ischemic cardiomyocytes at least up to 20 min. Less

甘油二酯激酶（DGK）是一种磷酸化第二信使甘油二酯（DG）的酶，参与多种病理生理细胞反应。我们以前曾报道，DGK的，其特点是核定位信号（NLS），从核转位到细胞质后，短暂前脑缺血20分钟的海马锥体神经元。然而，这一现象的详细机制及其功能意义仍不清楚。首先，我们使用暴露于氧和葡萄糖剥夺（OGD）的海马脑片来模拟脑缺血模型，并评估DGK β易位的时间过程。如在动物缺血模型中所见，OGD 20分钟后，DGK β-免疫反应性逐渐从细胞核转移到细胞质，再灌注后在细胞核中从未检测到。此外，我们发现，虽然OGD 10分钟时在核中检测到DGK β，但随后60分钟的再灌注诱导了细胞凋亡。 ...更多信息 DGK完全从细胞核转位到细胞质。这些结果表明，10分钟的OGD开关的信号级联，导致DGK β易位到cytoplasm.Second，我们的目的是看看是否DGK β的亚细胞定位的心肌细胞，这也是有丝分裂后，高度分化的细胞出生后的神经元缺血损伤后会发生变化。本实验首先采用夹闭大鼠左前降支分支的方法建立10 min短暂性缺血心脏模型。在非缺血间隔区，DGK β-免疫反应性观察到类似于正常条件下的心肌细胞核。然而，我们发现，免疫反应几乎消失，从心肌细胞核的缺血区。在缺血区的边缘区，DGK β免疫反应主要见于细胞核，细胞质中有微弱的表达。为了检查缺血的严重程度导致DGK β亚细胞定位的这种变化，我们产生了3分钟、5分钟和20分钟缺血的模型。令人惊讶的是，3分钟的缺血被证明足以导致DGK β从心肌细胞的细胞核中消失。从5分钟和20分钟缺血模型中获得了类似的结果。总的来说，在心脏缺血条件下，DGK从缺血心肌细胞的细胞核中迅速消失至少长达20分钟。

项目成果

血管平滑筋細胞におけるジアシルグリセロールキナーゼの発現・機能解析

二酰甘油激酶在血管平滑肌细胞中的表达及功能分析

• 发表时间: 2008
• 作者: 中野知之;若林一郎;後藤薫
• 通讯作者: 後藤薫

Diacylglycerol kinase zeta is involved in the process of cerebral infarction.

• 发表时间: 2006
• 期刊: The European journal of neuroscience
• 作者: T. Nakano;Y. Hozumi;H. Ali;Sachiko Saino-Saito;H. Kamii;Shinya Sato;T. Kayama;Masahiko Watanabe;H. Kondo;K. Goto

ベータ型ジアシルグリセロールキナーゼの海馬神経細胞内における局在と機能について

海马神经元β-二酰基甘油激酶的定位和功能

• 发表时间: 2008
• 作者: 八月朔日 泰和;後藤 薫
• 通讯作者: 後藤 薫

Heterogeneous response of nuclear DGKzeta in the process of cerebral infarction

核DGKzeta在脑梗死过程中的异质反应

• 发表时间: 2007
• 作者: Nakano T;Hozumi Y;Goto K
• 通讯作者: Goto K

ζ型ジアシルグリセロールキナーゼはp53と結合する

Zeta 型二酰甘油激酶结合 p53

• 发表时间: 2008
• 作者: 田中俊昭;後藤薫
• 通讯作者: 後藤薫