Gilbert R S, Herschman H R
Department of Biological Chemistry, UCLA School of Medicine 90024.
Biochem Biophys Res Commun. 1993 Aug 31;195(1):380-4. doi: 10.1006/bbrc.1993.2054.
Nitric oxide is a mediator of paracrine cell signalling. An inducible form of nitric oxide synthase (iNOS) is expressed in macrophages and in Swiss 3T3 cells. Transforming growth factor beta (TGF-beta) is a cytokine that modulates many cellular functions. We find that TGF-beta cannot induce iNOS mRNA expression, either in macrophage cell lines or in Swiss 3T3 cells. However, TGF-beta attenuates lipopolysaccharide induction of iNOS mRNA in macrophages. In contrast, TGF-beta enhances iNOS induction by phorbol ester, serum or lipopolysaccharide in 3T3 cells. Thus TGF-beta can inhibit or augment iNOS mRNA induction in response to primary inducers, depending on the cell type in question.
一氧化氮是旁分泌细胞信号传导的介质。一氧化氮合酶(iNOS)的一种诱导形式在巨噬细胞和瑞士3T3细胞中表达。转化生长因子β(TGF-β)是一种调节多种细胞功能的细胞因子。我们发现,TGF-β无论是在巨噬细胞系还是在瑞士3T3细胞中,都不能诱导iNOS mRNA表达。然而,TGF-β可减弱巨噬细胞中脂多糖对iNOS mRNA的诱导作用。相反,TGF-β可增强佛波酯、血清或脂多糖对3T3细胞中iNOS的诱导作用。因此,根据所涉及的细胞类型,TGF-β可抑制或增强对初级诱导剂的iNOS mRNA诱导作用。