Anti-allergic Activity And Mechanism Of Cyclic Adenosine Monophosphate In Jujube

As a foodborne disease,the occurrence frequency of food allergy has increased gradually.Currently,an effective way to prevent food allergy is to avoid eating allergens.Anti-allergic researches on natural products in foods have found that natural products alleviating food allergy has the advantages of effectiveness,fast action and small side effects.As a traditional Chinese food and medicine,red dates are rich in bioactive substance,cyclic adenosine monophosphate(cAMP).Acting as the secondary messenger,cAMP has potential anti-allergic effects in immune system for the function of regulating enzymes,hormones and other substances.In this study,ultrasonic assisted pectinase and ultra-high pressure techniques were used to extract cAMP from red dates to obtain the optimal process conditions.A peanut allergy mouse model,a sea shrimp allergy mouse model and a RBL-2H3 cell allergy model were constructed.The anti-allergic effect of cAMP was evaluated based on the three models,and the mechanism was preliminarily elucidated.The main conclusions are as follows:(1)The treatment conditions exerted different influence on ultrasound-assisted enzymatic extraction of cAMP from red dates:ratio of material to liquid>addition of pectinase>ultrasonic time>water bath temperature.The optimum extraction parameters were the ratio of material to liquid of 1:5,pectinase addition of 1.0%,water bath temperature of 45°C,ultrasonic time of 60 min,and optimum extraction yield was 783.0?g/g.(2)Using ultra-high pressure technology to extract cAMP from red dates,the order of influence of different treatment conditions on the extraction yield was material-liquid ratio>pressure>dwell time.The optimal extraction process parameters were pressure 300 MPa,dwell time 20 min and feed solution 1:2.5.The optimum extraction yield was 1223.29?g/g which was superior to ultrasonic-assisted pectin enzymatic method.(3)The peanut allergy mouse model was constructed by subcutaneous injection of peanut allergen protein.The clinical score of sensitized mice was significantly increased,and the phenomenon of scratching head and shortness of breath appeared accompanied by adverse reactions such as diarrhea and bloody stool.The spleen swelling,intestinal barrier damage,rise of inflammatory mediators such as Ig E and HIS and cytokines of IL-4 and L-10levels of Th2 type were observed.And cytokine TNF-?of Th1 type showed significant decrease.After 14 days of continuous gavage of cAMP,the clinical score and spleen index of the mice were significantly improved,and the intestinal function was repaired to some extent.The levels of Ig E,HIS and IL-4 in serum were significantly decreased,and the content of TNF-?was significantly increased.The results showed that cAMP inhibited the release of Ig E and HIS from mast cells,regulated cytokine levels,maintained Th1/Th2 balance,and relieved peanut allergy by improving immune function.(4)The mouse model of sea prawn allergy was constructed by subcutaneous injection of sea shrimp allergen protein.The clinical score of sensitized mice was significantly increased,and the phenomenon of scratching head and shortness of breath appeared accompanied by adverse reactions such as diarrhea and bloody stool.The spleen swelling,intestinal barrier damage,rise of inflammatory mediators such as Ig E and HIS and cytokines of IL-4 and L-10levels of Th2 type were observed.And cytokine TNF-?of Th1 type showed significant decrease.After 14 days of continuous gavage of cAMP,the clinical score and spleen index of the mice were significantly improved,and the intestinal function was repaired to some extent.The levels of Ig E,HIS and IL-4 in serum were significantly decreased,and the content of TNF-?was significantly increased.The results provided that cAMP inhibited sea shrimp allergy by inhibiting the release of Ig E and HIS from mast cells,regulating cytokine levels,maintaining Th1/Th2 balance,and improving immune function.(5)The allergy model of RBL-2H3 cells was constructed.The concentration of cAMP in RBL-2H3 cells should not be higher than 100?g/m L by MTT assay.The results showed that cAMP interfered with sensitized cells,effectively inhibited the occurrence of basophil degranulation,and significantly reduced the activity of?-Hex,at the optimal concentration of 50?g/m L.The level of anti-inflammatory factor IL-10 was promoted;content of pro-inflammatory factor TNF-?was suppressed by cAMP and in the meantime the influx of intracellular Ca²⁺was repressed.