Inhibition Of Chemically Induced Mouse Colitis With Polysaccharide Extracted From Agaricus Blazei Murill (ABM)

BackgroundInflammatory bowel disease(IBD)is a worldwide problem characterized by immune response dysfunction and membrane barrier damage with unknown etiology.Its incidence increase with age as well as socio-environmental factors.While the available treatment options of antibiotics,aminosalicylates,glucocorticoids or immunomodulators provide relief,their side effects and the possible outcome make them not user friendly.As such there is need to explore better and safer treatment options to this world problem.The mushrooms have been considered as a special delicacy by early civilizations,and valued as medicinal plants and credible source of nutrients including considerable amount of dietary fibers,minerals and vitamins.Mushroom contains a high amount of polysaccharides,these polysaccharides are considering as non-digestible fermentable carbohydrates that beneficially affect the host health by stimulating the production of beneficial bacteria and inhibit the pathogenic bacteria in the gastrointestinal tract.ObjectiveThe polysaccharide of Agaricus blazei Muril(ABM)was extracted,characterized and investigated for its effect on the development of intestinal colitis.MethodsThe Polysaccharide of ABM was extracted by using hot water and ethanol.Protein in the extract was removed by the Sevag reagent.The final product was processed by high performance liquid chromatography(HPLC)for monosaccharide analysis.The effect of ABM polysaccharide was evaluated on intestinal colitis using dextran sulfate sodium animal model in four groups;Control,DSS only,DSS and polysaccharide and Polysaccharide only.ABM polysaccharide was administered to polysaccharide groups for two weeks prior to colitis induction and then throughout the experiment.Intestinal colitis was induced by using 4%dextran sulfate sodium(DSS)in mice drinking water of DSS groups for 3 weeks following Polysaccharide treatment.Control group received no treatment.At the end of the experiment,colonic damage was histologically evaluated;inflammation was assessed by Myeloperoxidase(MPO)enzymatic activity;Alcian blue and nuclear fast red staining was assessed to estimate goblet cell production.Also,expression of Mucin 2(MUC2),trefoil factor 3(TFF3),hepatocyte growth factor(HGF),Cox-2 and NF-Kb cytokines in colonic samples were determined by Immunohistochemistry and Western Blotting analysis.ResultsThe percentage yield of polysaccharide obtained from ABM after extraction and purification was 2%.HPLC analysis of the polysaccharide extract of ABM revealed Rhamnose,fucose,arabinose,xylose,mannose,galactose,glucose,galacturonic acid and glucuronic acid as the major monosaccharide.Administration of the polysaccharide inhibited mouse colitis and correlated with increase in goblet cell production,MUC2,TFF3,and HGF involved in gut barrier function compared with DSS control.Also,ABM polysaccharide decreased inflammation associated proteins COX-2,NFKB and MPO activity but not in DSS group.AMB therefore,is a potential agent for the treatment of colitis through its anti-inflammatory activity and modulation of the intestinal gut barrier function.ConclusionAgaricus blazei Murill is an edible mushroom,which is effective for the treatment and prevention of IBD.Its polysaccharides,reduce histological damage of colonic mucosa,increase the production of anti-inflammatory cytokines by stimulating the production of goblet cell,and inhibit the production of proinflammatory cytokines production and inflammatory cell infiltration.