Repairing And Antioxidant Effects Of Polysaccharides From Lentinula Edodes On Acute Lung Injury

The polysaccharide from Lentinus edodes is an important active ingredient,has many pharmacological effects such as anti-tumor,anti-aging,anti-virus,anti-oxidation,anti-inflammation and immune regulation.In this work,plackett-burman(PB)and response surface methodology(RSM)were used to optimize the extraction conditions of polysaccharide of L.edodes(PLE).The structural components and the antioxidant abilities in vitro of PLE were analyzed.In addition,anti-inflammatory abilities and repairing effects against acute lung injury(ALI)in ZYM-induced multiple organ dysfunction syndrome(MODS)mice were also investigated.The results were shown below:(1)The optimum extraction conditions were ethanol concentration 86.84%,alcohol precipitation time 17.77 h and temperature 81.44℃,the theoretical yield of PLE was 1.99%.Considering the actual operation,the extraction conditions were set as ethanol concentration87%,alcohol precipitation time 18 h and temperature 81℃,the theory yield of PLE was1.99%and the actual yield was 1.92±0.15%.(2)Gel permeation chromatography(GPC)analysis showed that the weight-average molecular weight(Mw)was 2.22×10~5Da.High performance liquid chromatography(HPLC)analysis showed that the PLE primarily contained four monosaccharides including galacturonic acid(Glca),mannose(Man),galactose(Gal)and glucose(Glc)by the mass percentages of 2%,1.75%,2.59%and 93.66%with a molar ratio of 0.35:0.33:0.49:17.63.The results of Fourier transform infrared spectroscopy(FT-IR)and nuclear magnetic resonance spectroscopy(NMR)showed that PLE had typical characteristics of polysaccharides,and PLE was a pyran polysaccharide withβ-glucoside linked.(3)When the concentration of PLE was 1000 mg/L,the scavenging abilities of PLE on superoxide anion and hydroxyl radical were 42.58±2.88%and 50.76±2.56%,respectively.And the reducing power of PLE was 1.69±0.19.(4)The animal experiments results showed that H-PLE(400 mg/kg)significantly increased the levels of superoxide dismutase(SOD)and catalase(CAT)in lung tissue of mice,and decreased the content of malondiadehyde(MDA).The levels of tumor necrosis factor-α(TNF-α),interleukin-1β(IL-1β)and interleukin-6(IL-6)in lung tissue were significantly decreased.The serum levels of gamma-glutamyl transpeptidase(GGT),hypersensitive C-reactive protein(hs-CRP)and complement 3(C3)were significantly decreased.The results of Western blotting showed that,PLE could reduce the level of the pro-inflammatory factor p65and increase the level of the inflammation inhibitor I-κBα(Inhibitor of nuclear factor kappa-Bα)through the NF-κB pathway to alleviate the inflammatory response.PLE could improve the degree of inflammation in mice by hematoxylin and eosin(H&E)staining.These results indicated that PLE had anti-inflammatory activities in vivo,which can alleviate ALI to a certain extent and protect lung tissue,which provides reference for the development of natural anti-inflammatory and lung protective drugs.