Study on the Anti-inflammatory Effect of Stachyose by Inhibiting TLR4/NF-κB Signaling Pathway in Vitro and in Vivo.

This study aimed to explore the anti-inflammatory effect of stachyose, a tetrasaccharide extracted from Stachys sieboldii Miq. A lipopolysaccharide (LPS)-stimulated RAW264.7 macrophages model and a dextran sodium sulfate (DSS)-induced ulcerative colitis (UC) BALB/C mice model was used to assess the anti-inflammatory effect of stachyose both in vitro and in vivo. The levels of Nitric oxide (NO) and cytokines (Interleukin-1β, Interleukin-6, Tumor necrosis factor-α) were detected using enzyme-linked immunosorbent assay (ELISA) methods; besides, hematoxylin-eosin (HE) staining was used to observe changes in intestinal morphology of mice. In addition, the possible mechanisms were explored by reverse transcription-polymerase chain reaction (RT-qPCR) and western blot. Results showed that stachyose and four other oligosaccharides (galacto-oligosaccharides, xylo-oligosaccharides, inulin and resistant dextrin) inhibited NO secretion and the production of pro-inflammatory cytokines in LPS-stimulated RAW264.7 macrophages in a dose-dependent manner, while stachyose was most effective in vitro. In mice, different doses of stachyose significantly alleviated the symptoms of DSS-induced ulcerative colitis and stachyose also significantly inhibited the production of inflammatory cytokines and myeloperoxidase (MPO) in vivo. In addition, our findings illustrated that stachyose inhibited expression of TLR4 and suppressed the phosphorylation of NF-κB p65 both in vitro and in vivo. Taken together, results demonstrated that stachyose exerted anti-inflammatory effect through inhibition of the TLR4/NF-κB signaling pathway. This article is protected by copyright. All rights reserved.