Stuhlmeier K, Theyer G, Baumgartner G, Zlabinger G J
Institute of Immunology, University of Vienna, Austria.
Clin Exp Immunol. 1991 May;84(2):317-23. doi: 10.1111/j.1365-2249.1991.tb08167.x.
Coumarin as well as its derivatives 7-OH coumarin and 4-OH coumarin were found to stimulate interleukin-1 beta (IL-1 beta) release from freshly isolated human mononuclear cells (MNC) if the culture medium contained fetal calf serum. Under serum-free conditions, almost no induction of IL-1 beta release was observed and the former effect could be completely eliminated by polymyxin B. Therefore, the combined action of endotoxin and coumarin was tested on MNC IL-1 beta production. The coumarins were able to potentiate human MNC IL-1 beta production by lipopolysaccharide (LPS) in a dose-dependent manner. That the effect was due to the presence of coumarins and not endotoxin contamination was shown by negative Limulus amebocyte lysate tests and pre-incubation of the coumarins with polymyxin B-agarose. The latter procedure was able to block endotoxin induced IL-1 beta production but the synergism between coumarin and endotoxin was not influenced by pre-incubating the coumarins with polymyxin B-agarose. Cycloheximide as well as actinomycin D eliminated the induction of IL-1 release by coumarin and LPS demonstrating that the cytokine was newly synthesized after MNC stimulation. In addition, both the total amount of MNC IL-1 beta (cell-associated + extracellular) and the extracellular portion of the cytokine were synergistically decreased if coumarin or its derivatives were added to endotoxin-stimulated cultures. Synergism of coumarin and endotoxin in the induction of interleukin-6 or tumour necrosis factor-alpha could be observed in a smaller percentage of donors. These findings demonstrate an immunomodulatory effect of coumarin on cytokine production by monocytes in vitro which might help to explain some of the biological activities attributed to the drug upon its application in tumour patients.
如果培养基中含有胎牛血清，发现香豆素及其衍生物7-羟基香豆素和4-羟基香豆素能刺激新鲜分离的人单核细胞（MNC）释放白细胞介素-1β（IL-1β）。在无血清条件下，几乎未观察到IL-1β释放的诱导，且多粘菌素B可完全消除先前的效应。因此，对内毒素和香豆素对MNC产生IL-1β的联合作用进行了测试。香豆素能够以剂量依赖的方式增强脂多糖（LPS）诱导的人MNC产生IL-1β。鲎试剂阴性试验以及香豆素与多粘菌素B-琼脂糖的预孵育表明，该效应是由于香豆素的存在而非内毒素污染。后一程序能够阻断内毒素诱导的IL-1β产生，但香豆素与内毒素之间的协同作用不受香豆素与多粘菌素B-琼脂糖预孵育的影响。环己酰亚胺以及放线菌素D消除了香豆素和LPS对IL-1释放的诱导，表明细胞因子是在MNC刺激后新合成的。此外，如果将香豆素或其衍生物添加到内毒素刺激的培养物中，MNC产生的IL-1β总量（细胞相关+细胞外）以及细胞因子的细胞外部分均会协同减少。在较小比例的供体中可观察到香豆素与内毒素在诱导白细胞介素-6或肿瘤坏死因子-α方面的协同作用。这些发现证明了香豆素在体外对单核细胞产生细胞因子具有免疫调节作用，这可能有助于解释该药物应用于肿瘤患者时的一些生物学活性。
