Effect of β-Glucan Extracted from Saccharomyces cerevisiae on angiogenesis

This study was conducted for investigating the effect of β-glucan as anti-angiogenicagent and their immunological effect. Sample of dried Saccharomycescerevisiae were obtained from local market in Iraq, the identification has been confirmed the type of S. cerevisiaeby cultural, morphological and biochemical tests for the yeast. Glucan was extracted from yeast sample depended on alkalineacidic
hydrolysis method, the net dry weight of glucan was 8.8g / 100g of the yeast. Carbohydrates and proteins contents were determined for the glucan sample andresults indicated that the percentage of carbohydrates and proteins of glucan were 44% and0.45% respectively.The glucan was analyzed by the FT-IR and result confirmed that the extracted glucan showed high degree of similarity and purity as compared with the standard and the extracted glucan was considered asβ-glucan with the absences of other carbohydrate compound like mannan and glycogen.On the other hand HPLC analysis indicated thatthe extracted β- glucan had the same retention time as compared with the standard β-glucan.  The molecular weight of glucan was estimated by gel filtration chromatography usingSephacryl S-300 column.The detected molecular weight of the β-glucan was300 KDa. Evaluating the in vivoanti-angiogenic effect of β-glucanby CAM assay was carried out using fertilized eggs with age of 8 days.Different concentrations (250, 500, 750, 1000 and 1500 μg/egg) of β-glucan were used and in comparison with the negative control.Results showedthat the concentrations500, 750, 1000, 1500µg/ml had significant(P≤0.05) effects on the neovascularization that causedinhibitionof the fertilized eggangiogenesis, while the concentration 250µg/mlshowed no significant(P≤0.05) effect of the neovascularization.  Theeffect of phagocytic function of blood phagocytic cells toward yeast cell in the presence of β-glucan was determinedin vitro.Different concentrations (250, 500,750, 1000 and 1500µg/ml) of the β-glucan sample were used. Theconcentrations 500, 750, 1000 and 1500µg/mlhad a significant(P≤0.05) effect on increasing the phagocytosis function, butthe concentration 1500µg/ml was the most effective in increasing the phagocytosis rate to70%, while the concentration 250µm/ml had no significant effect on the phagocytosis assay. The mouse serum level of VEGF was evaluated after the intraperitoneal injection of the different concentration (10, 20,30,40,60 mg/Kg)of the β-glucanwas performed.It was found that20, 30, 40 and60mg/Kg had significant effectsin decreasing the level of the mouse VEGF, while 10mg/Kgshowed no effect on the mouse VEGF.