Scotto d'Abusco A, Cicione C, Calamia V, Negri R, Giordano C, Grigolo B, Politi L, Scandurra R
Department of Biochemical Sciences, CNR, Sapienza University of Rome, Rome, Italy.
Clin Exp Rheumatol. 2007 Nov-Dec;25(6):847-52.
Glucosamine (GlcN) is used in the treatment of osteoarthritis as symptomatic slow-acting drug, but its mode of action is not completely known. We analyzed the influence of GlcN and its N-acetyl-phenylalanine derivative (NAPA) on mRNA transcription level of TNF-alpha-stimulated genes in cell culture.
Human immortalized chondrocyte cell line lbpva55 was stimulated with TNF-alpha and treated with GlcN and NAPA. mRNA transcription level of several genes, identified by complementary DNA microarray (cDNA microarray), was validated by Quantitative Real-Time Polymerase Chain Reaction (Q-RT-PCR).
Several genes, whose mRNA level was increased by TNF-alpha treatment and significantly reduced by GlcN and NAPA in lbpva55 cells, were identified. These include cytokine receptors TNF-R1 and TNF-R2, their associated factor TRAF-6, signaling intermediates IGFB-6 and Rnd1, as well as cell cycle regulating proteins CUL-2 and G1S protein 1. Down- regulation of mRNA expression level of some of these genes is in accordance with inactivation of NF-kB transcription factor. Moreover, we found down-regulation of c-jun mRNA level, a component of AP-1 transcription factor.
Our study suggests that GlcN and NAPA interfere with activation of NF-kB and AP-1 transcription factors, which are responsible for the expression of genes involved in diverse biological processes, such as cell growth and death, inflammatory and stress responses, accounting for the beneficial effects of GlcN in osteoarthritis.
氨基葡萄糖（GlcN）作为一种症状性慢效药物用于骨关节炎的治疗，但其作用模式尚未完全明确。我们分析了GlcN及其N - 乙酰 - 苯丙氨酸衍生物（NAPA）对细胞培养中肿瘤坏死因子 - α（TNF - α）刺激基因的mRNA转录水平的影响。
用人永生化软骨细胞系lbpva55用TNF - α刺激并用GlcN和NAPA处理。通过互补DNA微阵列（cDNA微阵列）鉴定的几个基因的mRNA转录水平通过定量实时聚合酶链反应（Q - RT - PCR）进行验证。
在lbpva55细胞中，鉴定出了几个基因，其mRNA水平在TNF - α处理后升高，而在GlcN和NAPA处理后显著降低。这些基因包括细胞因子受体TNF - R1和TNF - R2、它们的相关因子TRAF - 6、信号中间体IGFB - 6和Rnd1，以及细胞周期调节蛋白CUL - 2和G1S蛋白1。其中一些基因的mRNA表达水平下调与核因子 - κB（NF - κB）转录因子的失活一致。此外，我们发现AP - 1转录因子的一个组成部分c - jun mRNA水平下调。
我们的研究表明，GlcN和NAPA干扰NF - κB和AP - 1转录因子的激活，这两种转录因子负责参与多种生物学过程的基因表达，如细胞生长和死亡、炎症和应激反应，这解释了GlcN在骨关节炎中的有益作用。
