Laboratory of Pharmacotherapy of Life-Style Related Diseases, Graduate School of Pharmaceutical Sciences, Tohoku University, Sendai 980-8578, Miyagi, Japan; Department of Pharmacy, Xijing Hospital, Fourth Military Medical University, Xi'an 710032, Shaanxi, PR China.
Laboratory of Pharmacotherapy of Life-Style Related Diseases, Graduate School of Pharmaceutical Sciences, Tohoku University, Sendai 980-8578, Miyagi, Japan.
Int Immunopharmacol. 2018 Feb;55:28-37. doi: 10.1016/j.intimp.2017.11.045. Epub 2017 Dec 22.
Thymic stromal lymphopoietin (TSLP) plays critical roles in inducing and exacerbating allergic diseases. Chemical compounds that induce TSLP production can enhance sensitization to antigens and exacerbate allergic inflammation. Hence, identifying such chemicals will be important to prevent an increase in allergic diseases. In the present study, we found, for the first time, that a steroid alkaloid derivative, code no. 02F04, concentration and time dependently induced mRNA expression and production of TSLP in a mouse keratinocyte cell line, PAM212. In particular, the activity of 02F04 was selective to TSLP. As an analogue of the liver X receptor (LXR) endogenous ligand, 02F04 rapidly increased ATP-binding cassette transporter A1 (ABCA1) expression by regulating the nuclear receptor of LXR. However, instead of being inhibited by the LXR antagonist, 02F04-induced TSLP production was delayed and markedly suppressed by inhibitors of phospholipase C (PLC), pan-protein kinase C (PKC), PKCδ, Rho-associated protein kinase (ROCK), extracellular signal-regulated kinase (ERK) 1/2, and IκΒ kinase 2 (IKK2). Treatment with 02F04 caused the formation of F-actin filaments surrounding the nucleus of PAM212 cells, which then disappeared following addition of ROCK inhibitor. 02F04 also induced phosphorylation of ERK1/2 from 2h after treatment, with a maximum at 24h, and increased nuclear factor-κB (NF-κB) promoter activity by 1.3-fold. Taken together, these results indicate that 02F04-induced TSLP production is regulated via distinct signal transduction pathways, including PLC, PKC, ROCK, ERK1/2, and NF-κB but not nuclear receptors. 02F04, with a unique skeletal structure in inducing TSLP production, can represent a potential new tool for investigating the role of TSLP in allergic diseases.
胸腺基质淋巴细胞生成素（TSLP）在诱导和加重过敏疾病方面发挥着关键作用。诱导 TSLP 产生的化学物质可以增强对抗原的致敏作用，并加重过敏炎症。因此，识别此类化学物质对于预防过敏疾病的增加非常重要。在本研究中，我们首次发现，一种甾体生物碱衍生物，编号为 02F04，可浓度和时间依赖性地诱导小鼠角质形成细胞系 PAM212 中 TSLP 的 mRNA 表达和产生。特别是，02F04 的活性对 TSLP 具有选择性。作为肝 X 受体（LXR）内源性配体的类似物，02F04 通过调节 LXR 的核受体，迅速增加三磷酸腺苷结合盒转运蛋白 A1（ABCA1）的表达。然而，与 LXR 拮抗剂的抑制作用相反，02F04 诱导的 TSLP 产生被磷脂酶 C（PLC）、全蛋白激酶 C（PKC）、PKCδ、Rho 相关蛋白激酶（ROCK）、细胞外信号调节激酶（ERK）1/2 和 IκΒ 激酶 2（IKK2）抑制剂延迟并显著抑制。用 02F04 处理导致 PAM212 细胞核周围 F-肌动蛋白丝的形成，随后加入 ROCK 抑制剂后消失。02F04 还在处理后 2 小时诱导 ERK1/2 的磷酸化，在 24 小时达到最大值，并使核因子-κB（NF-κB）启动子活性增加 1.3 倍。综上所述，这些结果表明，02F04 诱导的 TSLP 产生是通过包括 PLC、PKC、ROCK、ERK1/2 和 NF-κB 在内的不同信号转导途径调节的，但不涉及核受体。02F04 通过诱导 TSLP 产生的独特骨架结构，可以作为研究 TSLP 在过敏疾病中的作用的潜在新工具。
