College of Veterinary Medicine, Jilin University, Changchun, Jilin 130062, People's Republic of China.
College of Animal Science and Technology, Jilin Agricultural University, Changchun, People's Republic of China.
Eur J Pharmacol. 2017 Nov 5;814:138-143. doi: 10.1016/j.ejphar.2017.07.037. Epub 2017 Jul 20.
Platycodin D (PLD), a triterpenoid saponin derived from the root of Platycodon grandiflorum, has been reported to possess anti-inflammatory activity. However, the protective effect of PLD on mastitis has not been reported. In the present study, we aim to investigate the anti-inflammatory feature of PLD on the primary bovine mammary epithelial cells (bMEC) challenged with LPS. The cell viability of bMEC was measured by MTT assay. The quantitative real-time polymerase chain reaction (qRT-PCR) was conducted to detect the gene expression of pro-inflammatory cytokines and western blotting was carried out to measure the expression of LXRα and NF-κB. The results showed that PLD inhibited LPS-induced TNF-α, IL-1β, and IL-6 expression in LPS-stimulated bEMC. Meanwhile, PLD suppressed LPS-induced NF-κB activation. Furthermore, PLD was found to up-regulate the expression of LXRα. The inhibition of PLD on NF-κB activation and inflammatory cytokines production were reversed by GGPP, the inhibitor of LXRα. In conclusion, our results suggested that PLD inhibited LPS-induced inflammatory response in bMEC by activating LXRα. PLD may be a potential therapeutic drug for mastitis.
远志酸（PLD）是一种来源于桔梗的三萜皂苷，具有抗炎活性。然而，PLD 对乳腺炎的保护作用尚未见报道。在本研究中，我们旨在研究 PLD 对脂多糖刺激的原代牛乳腺上皮细胞（bMEC）的抗炎作用。通过 MTT 法测定 bMEC 的细胞活力。采用定量实时聚合酶链反应（qRT-PCR）检测促炎细胞因子的基因表达，采用 Western blot 检测 LXRα 和 NF-κB 的表达。结果表明，PLD 抑制 LPS 刺激的 bEMC 中 TNF-α、IL-1β 和 IL-6 的表达。同时，PLD 抑制 LPS 诱导的 NF-κB 激活。此外，还发现 PLD 可上调 LXRα 的表达。LXRα 的抑制剂 GGPP 逆转了 PLD 对 NF-κB 激活和炎症细胞因子产生的抑制作用。综上所述，我们的研究结果表明，PLD 通过激活 LXRα 抑制 bMEC 中 LPS 诱导的炎症反应。PLD 可能是乳腺炎的一种潜在治疗药物。
