Lycium ruthenicum polysaccharide attenuates inflammation through inhibiting TLR4/NF-κB signaling pathway

Polysaccharide has been reported to possess diverse biological activities, however, the inflammatory activity of polysaccharide isolated from Lycium ruthenicum remains unknown so far. In the present study, we investigated the effects of L. ruthenicum polysaccharide (LRGP3) on inflammatory reaction induced by lipopolysaccharide (LPS) in mouse macrophage RAW264.7 cells and some potential underlying mechanisms. Our results showed that LRGP3 treatment significantly inhibited the LPS-induced NO production and the mRNA expression of iNOS, as well as the level of Toll-like receptor 4 (TLR4). Furthermore, LRGP3 treatment prevented the IκBα degradation and reduced phospho-NF-κB p65 protein expression in LPS-stimulated RAW264.7 cells. Meanwhile, the levels of pro-inflammatory cytokines, such as interleukin (IL)-α, IL-6, tumor necrosis factor (TNF)-α were suppressed by LRGP3 in LPS-stimulated RAW264.7 cells. Taken together, our results suggested that LRGP3 attenuated LPS-induced inflammation via inhibiting TLR4/NF-κB signaling pathway.