Effect and Mechanism of Lycium Barbarum Polysaccharide on Hyperglycemia and Inflammation in Diabetic KKAy Mice

Abstract

Scope The aim of this study is to examine whether lycium barbarum polysaccharide (LBP) supplementation improves hyperglycemia and inflammation in diabetic KKAy mice. Methods The successfully established diabetic KKAy mice are randomized into five groups: diabetic model, metformin, low‐dose LBP, middle‐dose LBP, and high‐dose LBP . C57BL/6J mice are fed a chow diet as normal control . The blood glucose and body weight of mice were measured at different time points. At the end of 90 days, serum inflammatory factors were determined with ELISA kits. The expression of TLR4, MyD88, TRAF6, IκKβ, IκB, P-IκB and nuclear NF-κB proteins in mouse peritoneal macrophages were detected by Western Blotting. Results Blood glucose decreased significantly after the intervention among low-, medium-dose LBP groups and Met group ( P <0.05). Met (40 mg/kg) inhibited the levels of IL-1β, TNF-α and IL-6 and elevated IL-10 level ( P <0.05). ELISA results showed that LBP promoted serum levels of IL-10 and decreased TNF-α level ( P <0.05). Compared with model group, KKAy mice in Met group expressed lower protein levels of MyD88, TRAF6, IκKβ, nuclear NF-κB and higher expression of IκB ( P <0.05); The expression of TLR4, MyD88, TRAF6, IκKβ and nuclear NF-κB protein in low- and medium-doses LBP groups were significantly declined ( P <0.05). Conclusion These findings indicate that dietary supplementation with LBP can improve hyperglycemia and inflammation in diabetic KKAy mice, which can be associated with potential benefits to human health.