Sikora Anne-Sophie, Hellec Charles, Carpentier Mathieu, Martinez Pierre, Delos Maxime, Denys Agnès, Allain Fabrice
University of Lille, CNRS, UMR 8576-UGSF-Unité de Glycobiologie Structurale et Fonctionnelle, 59000 Lille, France.
University of Lille, CNRS, UMR 8576-UGSF-Unité de Glycobiologie Structurale et Fonctionnelle, 59000 Lille, France.
Int J Biochem Cell Biol. 2016 Nov;80:57-65. doi: 10.1016/j.biocel.2016.09.021. Epub 2016 Sep 28.
Heparan sulfate (HS) 6-O-endosulfatases (Sulfs) have emerged recently as critical regulators of many physiological and pathological processes. By removing 6-O-sulfates from specific HS sequences, they modulate the activities of a variety of growth factors and morphogens, including fibroblast growth factor (FGF)-1. However, little is known about the functions of Sulfs in inflammation. Tumour-necrosis factor (TNF)-α plays an important role in regulating the behaviour of fibroblasts. In this study, we examined the effect of this inflammatory cytokine on the expression of Sulfs in human MRC-5 fibroblasts. Compositional analysis of HS from TNF-α-treated cells showed a strong reduction in the amount of the trisulfated UA2S-GlcNS6S disaccharide, which suggested a selective reaction of 6-O-desulfation. Real-time PCR analysis revealed that TNF-α increased Sulf-1 expression in a dose- and time-dependent manner, via a mechanism involving NF-ĸB, ERK1/2 and p38 MAPK. In addition, we confirmed that cell stimulation with TNF-α was accompanied by the secretion of an active form of Sulf-1. To study the function of Sulf- 1, we examined the responses induced by FGF-1. We showed that ERK1/2 activation and cell proliferation were markedly reduced in TNF-α-treated MRC-5 cells compared with untreated cells. Silencing the expression of Sulf-1 by RNA interference restored the responses induced by FGF-1, which indicated that TNF-α-mediated induction of the sulfatase indeed resulted in alterations of HS biological properties. Taken together, our results indicate that Sulf-1 is responsive to TNF-α stimulation and may function as an autocrine regulator of fibroblast expansion in the course of an inflammatory response.
硫酸乙酰肝素（HS）6 - O - 硫酸酯酶（Sulfs）最近已成为许多生理和病理过程的关键调节因子。通过从特定的HS序列中去除6 - O - 硫酸盐，它们调节多种生长因子和形态发生素的活性，包括成纤维细胞生长因子（FGF）-1。然而，关于Sulfs在炎症中的功能知之甚少。肿瘤坏死因子（TNF）-α在调节成纤维细胞行为中起重要作用。在本研究中，我们研究了这种炎性细胞因子对人MRC - 5成纤维细胞中Sulfs表达的影响。对TNF - α处理细胞的HS进行成分分析表明，三硫酸化的UA2S - GlcNS6S二糖的量大幅减少，这表明存在6 - O - 去硫酸化的选择性反应。实时PCR分析显示，TNF - α通过涉及NF - κB、ERK1/2和p38 MAPK的机制，以剂量和时间依赖性方式增加Sulf - 1的表达。此外，我们证实TNF - α刺激细胞伴随着活性形式的Sulf - 1的分泌。为了研究Sulf - 1的功能，我们检测了FGF - 1诱导的反应。我们发现，与未处理的细胞相比，TNF - α处理的MRC - 5细胞中ERK1/2的激活和细胞增殖明显减少。通过RNA干扰使Sulf - 1的表达沉默可恢复FGF - 1诱导的反应，这表明TNF - α介导的硫酸酯酶诱导确实导致了HS生物学特性的改变。综上所述，我们的结果表明Sulf - 1对TNF - α刺激有反应，并且可能在炎症反应过程中作为成纤维细胞扩增的自分泌调节因子发挥作用。
