Regulation of nitric oxide (NO) synthesis and NO-induced apoptosis

一氧化氮 (NO) 合成和 NO 诱导的细胞凋亡的调节

• 批准号: 14370047
• 负责人: MORI Masataka
• 金额: $ 8.9万
• 依托单位: Kumamoto University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (B)
• 财政年份: 2002
• 资助国家: 日本
• 起止时间: 2002 至 2003
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-14370047/
• 关键词: nitric oxide; ER stress; apoptosis; CHOP; diabetes; 分子シヤペロン; マクロファージ

Endoplasmic reticulum (ER) is the site of synthesis and folding of secretory proteins. Purturbations of ER homrostasis affect protein folding and cause ER stress. Nitric oxide (NO) is a messenger molecule functioning in vascular regulation, immunity, neurotransmission and others, and has been implicated in many diseases. NO is synthesized from arginine by NO synthase (NOS), and the availability of arginine has been shown to be a rate-limiting factor in NO production. Citrulline formed as a by-product of the NOS reaction can be recycled to arginine by argininosuccinate synthetase and argininosuccinate lyase, forming the "citrulline-NO cycle". On the other hand, arginase isoforms have been shown to downregulate NO production by depleting arginine. Excessive NO leads to apoptosis in various cells. When macrophages were immunostimulated or treated with NO, apoptosis occurred. Under these conditions, p53 accumulation was not observed, indicating that DNA damage is not the main trigger of NO-mediated apoptosis. Furthermore, apoptosis was induced in p53-deficient microglial cells by NO. We found that CHOP/GADD153, a C/EBP family transcription factor which is involved in ER stress-mediated apoptosis, is induced. The induction of CHOP was followed by the mitochondrial apoptotic pathway involving cytochrome c release and activation of caspase cascade. Excessive NO production in cytokine-activated β-cells has been implicated in β-cell distruption in type 1 diabetes. NO depleted ER Ca^<2+>, and overexpression of calreticulin, a major Ca^<2+> binding protein in ER, increased ER Ca^<2+> and protected cells against NO-mediated apoptosis. Furthermore, pancreatic islets from CHOP-deficient mice showed resistance to NO. We conclude that NO depletes ER Ca^<2+>, causes ER stress, and leads to apoptosis.

内质网是分泌蛋白合成和折叠的场所。内质网稳态的破坏影响蛋白质折叠并引起内质网应激。一氧化氮（NO）是一种信使分子，在血管调节、免疫、神经传递等方面起作用，并与许多疾病有关。NO是由精氨酸通过NO合成酶（NOS）合成的，并且精氨酸的可用性已被证明是NO产生的限速因素。作为NOS反应的副产物形成的瓜氨酸可以通过氨基琥珀酸合成酶和氨基琥珀酸裂解酶再循环为精氨酸，形成“瓜氨酸-NO循环”。另一方面，已显示精氨酸酶同种型通过消耗精氨酸来下调NO产生。过量的NO导致多种细胞的凋亡。当巨噬细胞被免疫刺激或用NO处理时，发生凋亡。在这些条件下，没有观察到p53积累，表明DNA损伤不是NO介导的细胞凋亡的主要触发因素。此外，在p53缺陷的小胶质细胞的NO诱导凋亡。我们发现，CHOP/GADD 153，一个C/EBP家族的转录因子，参与ER应激介导的凋亡，诱导。CHOP的诱导之后是线粒体凋亡途径，涉及细胞色素c的释放和caspase级联的激活。在1型糖尿病中，精氨酸激活的β-细胞中过量的NO产生与β-细胞分布有关。NO消耗ER Ca^<2+>，钙网蛋白（ER中的一种主要Ca^<2+>结合蛋白）的过表达增加了ER Ca^<2+>并保护细胞免受NO介导的凋亡。此外，来自CHOP缺陷小鼠的胰岛显示出对NO的抵抗。我们得出结论，NO消耗ER Ca^<2+>，引起ER应激，并导致细胞凋亡。

项目成果

Oyadomari, S. et al.: "Endoplasmic reticulum stress-mediated apoptosis in pancreatic β-cells"Apoptosis. 7. 335-345 (2002)

Oyadomari，S.等人：“胰腺β细胞中内质网应激介导的细胞凋亡”细胞凋亡。

Abdul, K.Md.et al.: "Characterization and functional analysis of a heart-enriched DnaJ/Hsp40 homolog dj4/DjA4"Cell Stress Chaperones. 7. 156-166 (2002)

Abdul, K.Md. 等人：“心脏富集 DnaJ/Hsp40 同源物 dj4/DjA4 的表征和功能分析”细胞应激伴侣。

Inoue, Y. et al.: "Defective ureagenesis in mice carrying a liver-specific disruption of hepatocyte nuclear factor 4α(HNF4α). HNF4α regulates ornithine transcarbamylase in vivo"J.Biol.Chem.. 277. 25257-25265 (2002)

Inoue, Y. 等人：“携带肝细胞核因子 4α (HNF4α) 肝脏特异性破坏的小鼠中尿素生成缺陷。HNF4α 调节体内鸟氨酸转氨甲酰酶” J.Biol.Chem.. 277. 25257-25265 (2002)

Gotoh, T.et al.: "Nitric oxide-induced apoptosis in RAW 264.7 macrophages is mediated by endoplasmic reticulum stress pathway involving ATF6 and CHOP"J.Biol.Chem.. 277. 12343-12350 (2002)

Gotoh, T.等人：“RAW 264.7 巨噬细胞中一氧化氮诱导的细胞凋亡是由涉及 ATF6 和 CHOP 的内质网应激途径介导的”J.Biol.Chem.. 277. 12343-12350 (2002)

Gotoh, T.et al.: "Hsp70-DnaJ chaperone pair prevents nitric oxide- and CHOP-induced apoptosis by translocation of Bax to mitochondria"Cell Death Differ.. (in press). (2004)

Gotoh, T. 等人：“Hsp70-DnaJ 伴侣对通过 Bax 易位到线粒体来防止一氧化氮和 CHOP 诱导的细胞凋亡”细胞死亡差异..（出版中）。