| Objective: To prepare human anti-isomaltase IgY(I-IgY) and human anti-sucrase IgY(S-IgY), and study the effect of it on type 2 diabetes(T2DM) rats’ blood glucose. Methods: Preparation and identification of anti-human’s I-IgY and anti-human’s S-IgY: Laying chickens were immuned by recombinant human isomaltase and sucrase protein, IgY were purified by using the methods of Sodium sulfate water extraction. The protein content was measured by BCA method, the purity was analyzed by SDS-PAGE, the titer of the IgY was detected by indirect ELISA, the specificity was identified by Western blot. The inhibitory effect of IgY on human alpha-glycosidase enzymes was evaluate by PNPG method. Its thermal stability, pH stability, effect of pepsin and trypsin environment were evaluated by indirect ELISA, toxicity of IgY were observed in BALB/c mice. The establishment of typeⅡdiabetic rat model: SD rats were fed with high sugar and high fat feeds and injected with streptozocin(STZ) to induce typeⅡdiabetic rat model.control group A, T2 DM model control group B, I-IgY intervention group C, S-IgY intervention group D, acarbose intervention group E, the fasting glucose level was respectively measured after 2 weeks,3weeks and 4 weeks. The effectof anti-human’s I-IgY and S-IgY on the glucose tolerance of T2 DM rat: no feeding except drinking water for each group after 12 hours, normol controlgroup was given glucose solution, model group B was given glucose solution and 0.01mol/L PBS, group C was given glucose solution and anti-human’s isomaltase IgY, group D was given glucose solution and anti-human’s sucrase IgY, group E was given glucose solution and acarbose, the blood glucose of each group was measured after 0, 1 and 2 hours respectively. Results: The method of Sodium sulfate water dilution extraction could acquire high purity total protein content of IgY, The antibody titer of anti-human’s I-IgY and S-IgY was 1:12800. Western blot results showed both of the IgY could recognize antigen specifically. The half-inhibitory concentration(IC50) of anti-human’s I-IgY and S-IgY to alpha-glycosidase enzyme were 0.616 and 0.616 mg/m L respectively. The stability of anti-human’s S-IgY was better than I-IgY in acid and alkali stability and resistance to pepsin, but poor in resistance to trypsin. Compared with control group, anti-human’s S-IgY could reduce the FBG content of type 2 diabetes rat(P<0.05), Both of anti-human’s I-IgY and S-IgY could improve the glucose tolerance of diabetic rats(P<0.05). Conclusion: Both of anti-human’s I-IgY and S-IgY could improve the glucose tolerance of diabetic rats. Anti-human’s sucrase IgY could reduce the FBG content of T2 DM rat. |
