A Novel Carboline Derivative Inhibits Nitric Oxide Formation in Macrophages Independent of Effects on Tumor Necrosis Factor<i>α</i>and Interleukin-1<i>β</i>Expression
作者:Ana Cristina G. Grodzki、Bhaskar Poola、Nagarekha Pasupuleti、Michael H. Nantz、Pamela J. Lein、Fredric Gorin
DOI:10.1124/jpet.114.220186
日期:2015.3
Neuropathic pain is a maladaptive immune response to peripheral nerve injury that causes a chronic painful condition refractory to most analgesics. Nitric oxide (NO), which is produced by nitric oxide synthases (NOSs), has been implicated as a key factor in the pathogenesis of neuropathic pain. β -Carbolines are a large group of natural and synthetic indole alkaloids, some of which block activation of nuclear factor κ -light-chain-enhancer of activated B cells (NF- κ B), a predominant transcriptional regulator of NOS expression. Here, we characterize the inhibitory effects of a novel 6-chloro-8-(glycinyl)-amino- β -carboline (8-Gly carb) on NO formation and NF- κ B activation in macrophages. 8-Gly carb was significantly more potent than the NOS inhibitor NG-nitro-l-arginine methyl ester in inhibiting constitutive and inducible NO formation in primary rat macrophages. 8-Gly carb interfered with NF- κ B–mediated gene expression in differentiated THP1-XBlue cells, a human NF- κ B reporter macrophage cell line, but only at concentrations severalfold higher than needed to significantly inhibit NO production. 8-Gly carb also had no effect on tumor necrosis factor α (TNF α )–induced phosphorylation of the p38 mitogen-activated protein kinase in differentiated THP1 cells, and did not inhibit lipopolysaccharide- or TNF α -stimulated expression of TNF α and interleukin-1 β . These data demonstrate that relative to other carbolines and pharmacologic inhibitors of NOS, 8-Gly carb exhibits a unique pharmacological profile by inhibiting constitutive and inducible NO formation independent of NF- κ B activation and cytokine expression. Thus, this novel carboline derivative holds promise as a parent compound, leading to therapeutic agents that prevent the development of neuropathic pain mediated by macrophage-derived NO without interfering with cytokine expression required for neural recovery following peripheral nerve injury.
神经病理性疼痛是对周围神经损伤的一种适应不良的免疫反应,会导致大多数镇痛药难以奏效的慢性疼痛症状。一氧化氮(NO)由一氧化氮合酶(NOS)产生,已被认为是神经性疼痛发病机制中的一个关键因素。β-咔啉是一大类天然和合成的吲哚生物碱,其中一些可阻断活化 B 细胞的核因子κ-轻链增强子(NF- κ B)的活化,而 NF- κ B 是 NOS 表达的主要转录调节因子。在这里,我们描述了一种新型 6-氯-8-(甘氨酰)-氨基-β-咔啉(8-Gly carb)对巨噬细胞中 NO 的形成和 NF- κ B 的活化的抑制作用。在抑制原代大鼠巨噬细胞中组成型和诱导型 NO 的形成方面,8-Gly carb 的作用明显强于 NOS 抑制剂 NG-硝基-精氨酸甲酯。8-Gly carb 可干扰分化的 THP1-XBlue 细胞(一种人 NF-κ B 报告巨噬细胞系)中 NF-κ B 介导的基因表达,但只有在浓度比显著抑制 NO 生成所需的浓度高出数倍时才会起作用。8-Gly carb 对分化的 THP1 细胞中肿瘤坏死因子 α(TNF α)诱导的 p38 丝裂原活化蛋白激酶的磷酸化也没有影响,也没有抑制脂多糖或 TNF α 刺激的 TNF α 和白细胞介素-1 β 的表达。这些数据表明,与其他咔啉类化合物和 NOS 的药理抑制剂相比,8-Gly carb 具有独特的药理特性,它能抑制组成型和诱导型 NO 的形成,而不受 NF-κ B 激活和细胞因子表达的影响。因此,这种新型咔啉衍生物有望成为一种母体化合物,从而开发出既能防止由巨噬细胞源性 NO 介导的神经病理性疼痛的发生,又不干扰周围神经损伤后神经恢复所需的细胞因子表达的治疗药物。