Lieb K, Fiebich B L, Busse-Grawitz M, Hüll M, Berger M, Bauer J
Abteilung Psychiatrie und Psychotherapie, Universität Freiburg, Germany.
J Neuroimmunol. 1996 Jul;67(2):77-81. doi: 10.1016/0165-5728(96)00034-3.
Recent studies have suggested that substance P (SP) and some other neuropeptides are able to induce the synthesis of the proinflammatory cytokines interleukin-1 (IL-1) and interleukin-6 (IL-6) in peripheral blood mononuclear cells. In the present study, we re-examined these findings by using a completely endotoxin-free monocyte cultivation system. We demonstrate that the neuropeptides SP, vasoactive intestinal peptide, substance K. cholecytokinine, alpha-endorphin and beta-endorphin are consistently unable to induce the synthesis of IL-1 and IL-6 in human peripheral blood monocytes. However, low amounts of LPS (1 pg/ml) synergized with SP to induce IL-6 mRNA expression. In contrast to its lack of effect in monocytes, we were able to confirm the ability of SP to induce cytokine synthesis in astrocytic cells. Our results raise questions about previous results claiming a neuropeptide-induced synthesis of proinflammatory cytokines in human monocytes. In conjunction with other studies, we suggest that undetected levels of endotoxin/LPS in the culture medium may have been primarily responsible for results suggesting an inductive effect of neuropeptides on cytokine synthesis in monocytes.
最近的研究表明，P物质（SP）和其他一些神经肽能够在外周血单核细胞中诱导促炎细胞因子白细胞介素-1（IL-1）和白细胞介素-6（IL-6）的合成。在本研究中，我们使用完全无内毒素的单核细胞培养系统重新检验了这些发现。我们证明，神经肽SP、血管活性肠肽、物质K、胆囊收缩素、α-内啡肽和β-内啡肽始终无法诱导人外周血单核细胞中IL-1和IL-6的合成。然而，低剂量的脂多糖（LPS，1 pg/ml）与SP协同作用可诱导IL-6 mRNA表达。与其在单核细胞中缺乏作用相反，我们能够证实SP在星形细胞中诱导细胞因子合成的能力。我们的结果对先前声称神经肽可诱导人单核细胞中促炎细胞因子合成的结果提出了质疑。结合其他研究，我们认为培养基中未检测到的内毒素/LPS水平可能是导致提示神经肽对单核细胞中细胞因子合成有诱导作用结果的主要原因。
