NF-κB plays an important role in indoxyl sulfate-induced cellular senescence, fibrotic gene expression, and inhibition of proliferation in proximal tubular cells
NF-κB plays an important role in indoxyl sulfate-induced cellular senescence, fibrotic gene expression, and inhibition of proliferation in proximal tubular cells
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DOI：
10.1152/ajpcell.00471.2010
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发表时间：
2011-11-01
影响因子：
5.5
通讯作者：
Niwa, Toshimitsu
中科院分区：
文献类型：
--
作者：
Shimizu, Hidehisa;Bolati, Dilinaer;Niwa, Toshimitsu
Shimizu H, Bolati D, Adi Jiang A, Muteliefu G, Enomoto A, Nishijima F, Dateki M, Niwa T. NF-kappa B 在硫酸吲哚酚诱导的细胞衰老、纤维化基因表达和近端肾小管细胞增殖抑制中发挥重要作用。 Am J Physiol Cell Physiol 301：C1201-C1212，2011。首次发表于 2011 年 8 月 10 日； doi:10.1152/ajpcell.00471.2010.-我们之前证明硫酸吲哚酚通过激活 p53 表达诱导近端肾小管细胞衰老和功能障碍。然而，人们对核因子 (NF)-kappa B 在这些过程中的作用知之甚少。本研究探讨了硫酸吲哚酚对 NF-κ B 的激活（磷酸化）是否会促进人近端肾小管细胞（HK-2 细胞）的衰老和功能障碍。硫酸吲哚酚诱导 NF-kappa B p65 在 Ser-276 上的磷酸化，该磷酸化被抗氧化剂 N-乙酰半胱氨酸抑制。此外，硫酸吲哚酚诱导 NF-κB p65 表达。 NF-κ B 抑制剂（吡咯烷二硫代氨基甲酸酯和异海葵素）和 NF-κ B p65 小干扰 RNA (siRNA) 抑制硫酸吲哚酚诱导的衰老相关 β-半乳糖苷酶活性以及 p53、转化生长因子 (TGF)-β 1 和 α-平滑肌肌动蛋白 (SMA) 的表达。硫酸吲哚酚诱导的p53表达和p53启动子活性被p53抑制剂pifithrin-α，p-硝基抑制，而p53转染的细胞显示出增强的p53启动子活性。 NF-kappa B 抑制剂抑制硫酸吲哚酚诱导的 p21 表达，而 NF-kappa B p65 siRNA 增强其表达。 NF-κ B 抑制剂部分减轻硫酸吲哚酚诱导的细胞增殖抑制。 NF-κB p65 siRNA 转染细胞在硫酸吲哚酚存在下显示出比对照细胞更少的增殖。磷酸化 NF-κ B p65 在慢性肾衰竭 (CRF) 大鼠的肾脏中表达并与 p53、p21、β-半乳糖苷酶、TGF-β 1 和 α-SMA 共定位。 AST-120 可降低血清硫酸吲哚酚水平，抑制其在 CRF 大鼠肾脏中的表达。总之，NF-κ B 在硫酸吲哚酚诱导的细胞衰老、纤维化基因表达和近端肾小管细胞增殖抑制中发挥重要作用。更值得注意的是，硫酸吲哚酚通过活性氧-NF-κ B-p53 途径加速近端肾小管细胞衰老，导致 CRF 进展。
Shimizu H, Bolati D, Adijiang A, Muteliefu G, Enomoto A, Nishijima F, Dateki M, Niwa T. NF-kappa B plays an important role in indoxyl sulfate-induced cellular senescence, fibrotic gene expression, and inhibition of proliferation in proximal tubular cells. Am J Physiol Cell Physiol 301: C1201-C1212, 2011. First published August 10, 2011; doi:10.1152/ajpcell.00471.2010.-We previously demonstrated that indoxyl sulfate induces senescence and dysfunction of proximal tubular cells by activating p53 expression. However, little is known about the role of nuclear factor (NF)-kappa B in these processes. The present study examines whether activation (phosphorylation) of NF-kappa B by indoxyl sulfate promotes senescence and dysfunction in human proximal tubular cells (HK-2 cells). Indoxyl sulfate induced phosphorylation of NF-kappa B p65 on Ser-276, which was suppressed by N-acetylcysteine, an antioxidant. Furthermore, indoxyl sulfate induced NF-kappa B p65 expression. Inhibitors of NF-kappa B (pyrrolidine dithiocarbamate and isohelenin) and NF-kappa B p65 small interfering RNA (siRNA) suppressed indoxyl sulfate-induced senescence-associated beta-galactosidase activity and expression of p53, transforming growth factor (TGF)-beta 1, and alpha-smoothe muscle actin (SMA). The induction of p53 expression and p53 promoter activity by indoxyl sulfate were inhibited by pifithrin-alpha, p-nitro, an inhibitor of p53, whereas p53-transfected cells showed enhanced p53 promoter activity. NF-kappa B inhibitors suppressed indoxyl sulfate-induced p21 expression, whereas NF-kappa B p65 siRNA enhanced its expression. NF-kappa B inhibitors partially alleviated indoxyl sulfate-induced inhibition of cellular proliferation. NF-kappa B p65 siRNA-transfected cells showed less proliferation in the presence of indoxyl sulfate than control cells. Phosphorylated NF-kappa B p65 was expressed and colocalized with p53, p21, beta-galactosidase, TGF-beta 1, and alpha-SMA in the kidneys of chronic renal failure (CRF) rats. AST-120, which reduces serum indoxyl sulfate level, suppressed their expression in the CRF rat kidneys. Taken together, NF-kappa B plays an important role in indoxyl sulfate-induced cellular senescence, fibrotic gene expression, and inhibition of proliferation in proximal tubular cells. More notably, indoxyl sulfate accelerates proximal tubular cell senescence with progression of CRF through reactive oxygen species-NF-kappa B-p53 pathway.