Guangzhou University of Chinese Medicine, Guangzhou 510006, Guangdong, PR China; Guangdong Provincial Key Laboratory of New Drug Development and Research of Chinese Medicine, Guangzhou 510006, Guangdong, PR China.
Department of Hepatobiliary Surgery, The Third Affiliated Hospital of Sun Yat-Sen University, Guangzhou, Guangdong, PR China.
Int J Biol Macromol. 2018 Feb;107(Pt B):2201-2210. doi: 10.1016/j.ijbiomac.2017.10.085. Epub 2017 Oct 23.
The purpose of this study was to investigate the protective roles and mechanisms of Dendrobium officinale polysaccharides (DOPS) on secondary liver injury in acute colitis. Firstly, the mice model of secondary liver injury in acute colitis was induced by 4% Dextran sodium sulfate (DSS). Inflammatory cell model was established by LPS-stimulated RAW264.7 cells. Then, the protective roles of DOPS were evaluated by both in vivo and in vitro experiment. The results showed that DOPS attenuated DSS-induced hepatic pathological damage, liver parameters, infiltration of macrophages, cytokines levels, MDA level and increased the antioxidant enzymes activities. In vitro, DOPS markedly inhibited inflammatory cytokines production and increased antioxidant enzymes activities. Finally, its molecular mechanisms were also observed. The results indicated that DOPS could down-regulated TNF-α signaling pathway and activated Nrf-2 signaling pathway in vivo and in vitro. These results suggested that DOPS may be an effective therapeutic reagent to attenuate secondary liver injury in acute colitis.
本研究旨在探讨铁皮石斛多糖（DOPS）对急性结肠炎继发肝损伤的保护作用及其机制。首先，采用 4%葡聚糖硫酸钠（DSS）诱导小鼠急性结肠炎继发肝损伤模型，用 LPS 刺激 RAW264.7 细胞建立炎症细胞模型。然后，通过体内和体外实验评估 DOPS 的保护作用。结果表明，DOPS 可减轻 DSS 诱导的肝组织病理损伤、肝损伤标志物、巨噬细胞浸润、细胞因子水平、MDA 水平，提高抗氧化酶活性。体外实验结果表明，DOPS 可显著抑制炎症细胞因子的产生，提高抗氧化酶活性。最后，观察其分子机制。结果表明，DOPS 可下调 TNF-α 信号通路，在体内和体外激活 Nrf-2 信号通路。这些结果表明，DOPS 可能是减轻急性结肠炎继发肝损伤的有效治疗试剂。
