Anti-food Allergy Activity Of Eucheuma Cottonii Sulfated Oligosaccharide

Food allergy mainly refers to the adverse reactions mediated by the human body to the antigen substances in food,and its clinical manifestations are often manifested in the digestive tract,skin,respiratory system and other diseases.In order to effectively alleviate the allergic symptoms of food allergy patients,there are anti-histamine and other drug treatment,but the drug treatment has a large side effects,and can not cure the food allergy.Natural active substances replaceed drug treatment to relieve allergic symptoms of allergic patients is the focus of the current study.In this study,Eucheuma Cottonii sulfated oligosaccharide were obtained by enzymolysis,centrifugation,and ultrafiltration,low pressure vacuum concentration,DEAE-cellulose 52 column chromatography and Detoxi-Gel endotoxin removal column chromatography.The total sugar content of ESO was 97.87%.The results of infrared spectroscopy showed that the oligosaccharides contained the characteristic absorption peak of sulfate,and the content of sulfate was 18.17% and the protein content was 1.03%.The results showed that the monosaccharides of ESO were composed of tetrasaccharide and hexose,and the molecular weights were 796 Da and 2112 Da,respectively.In this study,the anti allergic activity of ESO and its mechanism were investigated in vitro and in vivo model.In vitro experimental model RBL-2H3 cell model,the results showed that the ESOcould significantly inhibit the degranulation,histamine,IL-4 and TNF-α of mast cells.The results of model of bone marrow-derived mast cells(BMMCs)showed that ESO could specifically induce apoptosis of BMMCs after activation of TM,but no significant effect on unactivated BMMCs.A model of food allergy in mice was established by using tropomyosin(TM)as an allergen,to study the anti-allergic activity of ESO as an in vivo model.The results of mouse model showed that ESO can significantly alleviate the diarrhea of food allergy,hypothermia and other allergic symptoms.The results of ELISA showed that the ESO could significantly reduce the levels of serum IgE,IgG1,histamine.Meanwhile,the levels of IL-4 and IL-13 of spleen and mesentery lymphocytes were significantly lower than those in the TM group(P <0.05),IFN-gama and IL-10 were higher than those in the TM group.The results of gene level showed that ESO could significantly down-regulate the ratio of Th2-related transcription factor GATA-3 to Th1-related transcription factor T-bet,up-regulate Treg-related transcription Factor Foxp3 expression.The results of flow cytometry showed that the ESO could significantly promote the differentiation of Treg cells from spleen and mesenteric.In conclusion,the results of cell model showed that ESO could significantly inhibit the activation of RBL-2H3 cells and specifically induce the apoptosis of BMMCs.The results of mouse model indicated that ESO could promote the polarization of Treg cells,inhibition of Th2 cell function,thereby reducing the release of allergic media.The ESO have obvious anti-food allergic activity.