MECHANISM OF GALACTOSAMINE-INDUCED HEPATOCYTE APOPTOSIS

半乳糖胺诱导肝细胞凋亡的机制

• 批准号: 07456139
• 负责人: DOI Kunio
• 金额: $ 4.22万
• 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 (B)
• 财政年份: 1995
• 资助国家: 日本
• 起止时间: 1995 至 1996
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-07456139/
• 关键词: APOPTOSIS; GALACTOSAMITE; HEPATOCYTE; Ca^<2+>; T-2 toxin; 5-AZACYTIDINE; APOPTOSIS; アポートシス; マウス

Details of galactosamine (GalN)-induced apoptosis in mouse hepatocytes were investigated. In the primary hepatocyte cultures treated with GalN,DNA-fragmentation was detected prior to LDH-release from cells to culture medium, and apoptosis was followed by necrosis in the high dose group (20mM). Hepatocyte apoptosis was also induced in mice at 24 hr after GalN-treatment (3mg/kg), and apoptosis was also followed by necrosis in this case.Immediately after GalN-treatment, an intracellular Ca^<2+>-concentration arose sharply in the primary hepatocyte cultures. In addition, CPZ (Ca^<2+>-calmodulin antagonist) and VR (Ca^<2+>-channel blocker) effectively suppressed hepatocyte apoptosis both in in vitro and in vivo systems when they were administered before GalN-treatment, and this suggests that a rapid increase in intracellular Ca^<2+>-concentration may play an important role in the development of GalN-induced hepatocyte apoptosis. Now we are trying to elucidate why GalN-treatment induces a rapid Ca^<2+>-influx into hepatocytes. On the other hand, hepatocyte necrosis was not suppressed by CPZ- and VR-treatment. Moreover, Fas and p53 had no relation to the induction of apoptosis by GalN.The mechanism of GalN-induced hapatocyte apoptosis seems to be different from those of T-2 toxin-induced lymphocytic apoptosis and of 5-azacytidine-induced neuronnal apoptosis which were also examined in the present project from the comparative viewpoints.

研究了半乳糖胺（GalN）诱导小鼠肝细胞凋亡的详细情况。在用GalN处理的原代肝细胞培养物中，在LDH从细胞释放到培养基之前检测到DNA片段化，并且在高剂量组（20 mM）中凋亡随后是坏死。GalN（3 mg/kg）处理后24小时，小鼠肝细胞也出现凋亡，凋亡后肝细胞坏死，原代培养的肝细胞内Ca^<2+>-浓度在GalN处理后立即急剧升高。此外，在GalN处理前给予CPZ（Ca^2+-钙调素拮抗剂）和VR（Ca^2+-通道阻滞剂），在体外和体内系统中均有效地抑制肝细胞凋亡，这表明细胞内Ca^2+浓度的快速增加可能在GalN诱导的肝细胞凋亡的发展中起重要作用。现在我们试图阐明为什么GalN处理会诱导Ca^<2+>-快速流入肝细胞。另一方面，CPZ和VR治疗不能抑制肝细胞坏死。GalN诱导肝细胞凋亡的机制与T-2毒素诱导的淋巴细胞凋亡和5-氮胞苷诱导的神经元凋亡的机制不同。

项目成果

Tutsui S., Hirawasa K., Takeda M., Itagaki S., Kawamura S., Maeda K., Mikami T.and Doi K.: "Galactosamine-induced apoptosis in the primary hepatocyte culture" Exp.Toxicol.Pathol.49, (in press). (1997)

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Tsutsui S.et al: "Galactosamine-induced apoptosis in the primary mouse hepatocyte culture." Exp.Toxicol.Pathol.49(in press). (1997)

Tsutsui S.et al：“原代小鼠肝细胞培养物中半乳糖胺诱导的细胞凋亡。”

Hossain MM., Nakayama H., and Goto N.: "In vitro induction of apoptosis of developing brain cells by 5-azacytidine" Int.J.Develop.Neurosci.14. 11-17 (1996)

Hossain MM.、Nakayama H. 和 Goto N.：“5-氮杂胞苷体外诱导发育中脑细胞凋亡”Int.J.Develop.Neurosci.14。

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Shinozuka J.et al.：“T-2 毒素诱导小鼠淋巴器官细胞凋亡”实验。

Li GM,.Shinozuka J., Uetsuka K., Nakayama H.and Doi K.: "T-2 toxin-induced apoptosis in Peyer's patches of mice" J.Toxicol.Pathol.10, (in press). (1997)

Li GM、Shinozuka J.、Uetsuka K.、Nakayama H. 和 Doi K.：“T-2 毒素诱导小鼠派尔氏斑的细胞凋亡”J.Toxicol.Pathol.10，（出版中）。