Zhang Y H, Kato M, Isobe K, Hamaguchi M, Yokochi T, Nakashima I
Department of Immunology, Nagoya University School of Medicine, Japan.
Cell Immunol. 1995 Apr 15;162(1):97-104. doi: 10.1006/cimm.1995.1056.
The action of glycyrrhizin (GL) modulating the proliferation and IL-2 production of murine thymocytes in response to anti-CD3 and concanavalin A was studied. Different from the previously reported GL effect of accelerating both IL-2 production and proliferation of mature T lymphocytes, GL displayed a dissociated action on immature thymocytes promoting IL-2 production/IL-2 receptor expression but inhibiting cell growth. Hydrocortisone-resistant mature thymocytes behaved like peripheral T lymphocytes, demonstrating the dependency of the GL action on cell maturation stage. GL-mediated growth inhibition of thymocytes was not due the cytotoxic action of GL that induces cell death or DNA fragmentation. In parallel to these dissociated actions, GL promoted the tyrosine phosphorylation of p56 but suppressed the phosphorylation of p40 induced by anti-CD3. Moreover, GL and anti-CD3 showed a combination effect suppressing the transcription of c-fos, which was promoted by anti-CD3 alone or GL alone. It is suggested that whereas mature and immature T cells share a common signal pathway for IL-2 production augmented by the action of GL, they have signaling steps for DNA synthesis which are under different mechanisms receiving the modulation effects of GL in opposite directions.
研究了甘草酸（GL）对小鼠胸腺细胞在抗CD3和伴刀豆球蛋白A刺激下增殖及白细胞介素-2（IL-2）产生的调节作用。与先前报道的GL促进成熟T淋巴细胞IL-2产生和增殖的作用不同，GL对未成熟胸腺细胞表现出解离作用，即促进IL-2产生/IL-2受体表达但抑制细胞生长。氢化可的松抗性成熟胸腺细胞的行为类似于外周T淋巴细胞，表明GL作用对细胞成熟阶段的依赖性。GL介导的胸腺细胞生长抑制并非由于GL诱导细胞死亡或DNA片段化的细胞毒性作用。与这些解离作用并行的是，GL促进p56的酪氨酸磷酸化，但抑制抗CD3诱导的p40磷酸化。此外，GL和抗CD3显示出联合作用抑制c-fos的转录，单独的抗CD3或GL均可促进c-fos的转录。提示成熟和未成熟T细胞在GL作用增强IL-2产生方面共享一个共同的信号通路，但它们具有DNA合成的信号传导步骤，这些步骤处于不同机制下，接受GL相反方向的调节作用。
