Lotus (Nelumbo nucifera Gaertn) plumule polysaccharide protects the spleen and liver from spontaneous inflammation in non-obese diabetic mice by modulating pro-/anti-inflammatory cytokine gene expression

A novel lotus plumule polysaccharide (LPPS) was administered to non-obese diabetic (NOD) mice for 15 weeks to evaluate the protective effects of LPPS on type 1 diabetes. After the 15-week feeding experiment, tumour necrosis factor (TNF)-α, interleukin (IL)-6 and IL-10 expressions in the spleen, liver and kidney of the experimental mice were measured using enzyme-linked immunosorbent assay or real-time quantitative polymerase chain reaction assay. The results showed that LPPS significantly (p < 0.05) decreased the absolute weights of the enlarged spleens in the NOD mice in a dose-dependent manner, inhibited pro-inflammatory TNF-α and IL-6 cytokine production and decreased the secretion ratio of IL-6/IL-10 in splenocyte cultures. LPPS markedly decreased the relative expression of pro-/anti-inflammatory cytokine genes (TNF-α/IL-10 and IL-6/IL-10) in the livers of NOD mice. Our results suggest that LPPS protected the spleen and liver from spontaneous inflammation in NOD mice by modulating pro-/anti-inflammatory cytokine gene expression.