Jones S, Jones S, Phillips A O
Institute of Nephrology, University of Wales College of Medicine, Heath Park, Cardiff, Wales, United Kingdom.
Kidney Int. 2001 May;59(5):1739-49. doi: 10.1046/j.1523-1755.2001.0590051739.x.
Proximal tubular cells (PTCs) contribute to pathological changes in the renal interstitium by the generation of cytokines and alterations in the composition of the extracellular matrix. Hyaluronan (HA) is a ubiquitous connective tissue polysaccharide that regulates cell function and tissue remodeling. In the current study, we investigated the regulation of HA generation by PTCs.
Primary cultures of human PTCs were grown to confluence and stimulated under serum-free conditions with either interleukin-1 (IL-1) or 25 mmol/L D-glucose. Alterations in HA generation were detected by enzyme-linked immunosorbent assay, and alterations in HA synthase gene expression were examined by reverse transcription-polymerase chain reaction. Subsequently, the mechanisms of IL-1 beta and glucose-induced alterations in HA were examined utilizing HK-2 cells.
Stimulation of human PTCs (HPTCs) with either IL-1 beta or 25 mmol/L D-glucose led to a significant increase in the HA concentration in the culture supernatant. In contrast, stimulation of HPTCs with transforming growth factor-beta1, basic fibroblast growth factor, or platelet-derived growth factor-AB did not stimulate HA production. The addition of IL-1 beta or 25 mmol/L D-glucose also increased HA generation in HK-2 cells and was associated with the induction of HAS2 mRNA. HAS3 mRNA was constitutively expressed and was not influenced by the addition of either stimulus. HAS1 mRNA expression was not detected in either unstimulated or stimulated cells. Inhibition of gene transcription or protein synthesis abolished HA production in response to either IL-1 beta or glucose. Inhibition of nuclear factor-kappa B (NF-kappa B) activation either by sulindac or by the proteosome inhibitor (PSI) abrogated both IL-1 beta and glucose-mediated alteration in HA synthesis.
This study demonstrates, to our knowledge for the first time, that increased HA synthesis in response to either IL-1 beta or elevated 25 mmol/L D-glucose is associated with NF-kappa B-activated transcription of HAS2.
近端肾小管细胞（PTCs）通过细胞因子的产生和细胞外基质成分的改变，参与肾间质的病理变化。透明质酸（HA）是一种普遍存在的结缔组织多糖，可调节细胞功能和组织重塑。在本研究中，我们调查了PTCs对HA生成的调控。
将人PTCs原代培养至汇合状态，并在无血清条件下用白细胞介素-1（IL-1）或25 mmol/L D-葡萄糖进行刺激。通过酶联免疫吸附测定法检测HA生成的变化，并用逆转录-聚合酶链反应检测HA合酶基因表达的变化。随后，利用HK-2细胞研究IL-1β和葡萄糖诱导HA变化的机制。
用IL-1β或25 mmol/L D-葡萄糖刺激人PTCs（HPTCs）导致培养上清液中HA浓度显著增加。相比之下，用转化生长因子-β1、碱性成纤维细胞生长因子或血小板衍生生长因子-AB刺激HPTCs不会刺激HA产生。添加IL-1β或25 mmol/L D-葡萄糖也增加了HK-2细胞中HA的生成，并与HAS2 mRNA的诱导相关。HAS3 mRNA组成性表达，不受任何一种刺激物添加的影响。在未刺激或刺激的细胞中均未检测到HAS1 mRNA表达。抑制基因转录或蛋白质合成可消除对IL-1β或葡萄糖的HA产生反应。通过舒林酸或蛋白酶体抑制剂（PSI）抑制核因子-κB（NF-κB）激活可消除IL-1β和葡萄糖介导的HA合成变化。
据我们所知，本研究首次证明，对IL-1β或升高的25 mmol/L D-葡萄糖的反应中HA合成增加与NF-κB激活的HAS2转录有关。
