Anti-food allergic activity of sulfated polysaccharide from gracilaria lemaneiformis is dependent on immunosuppression and inhibition of p38 mapk

Authors: LIU, QUING-MEI - Jimei University; YANG, YANG ZHANG - Jimei University; Maleki, Soheila; ALCOCER, MARCOS - University Of Nottingham; XU, SHA-SHA - Jimei University; SHI, CHAO-LAN - Jimei University; CAO, MIN-JIE - Jimei University; LIU, GUANG-MING - Jimei University

Submitted to: Journal of Agricultural and Food Chemistry
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 5/17/2016
Publication Date: 5/17/2016
Citation: Liu, Q., Yang, Y., Maleki, S.J., Alcocer, M., Xu, S., Shi, C., Cao, M., Liu, G. 2016. Anti-food allergic activity of sulfated polysaccharide from gracilaria lemaneiformis is dependent on immunosuppression and inhibition of p38 mapk. Journal of Agricultural and Food Chemistry. 64:4536-4544.

Interpretive Summary: Sugars obtained from marine sources offer diverse therapeutic functions due to their multifunctional biological nature. Sugars from Gracilaria lemaneiformis, a type of red algae, possess various bioactive functions, but its anti-allergic activity is less understood. Objective: This study aimed to extract and analyze sugars modified with sulfate molecules from Gracilaria lemaneiformis (GLSP), which is a type of seaweed, to investigate its anti-allergic mechanisms in cells and animals. Methods: GLSP was obtained by water extraction, ethanol treatment, and chromatography. Shrimp allergic mice were treated with GLSP for preventive and treatment groups. The effects of GLSP on the function of allergic cell lines were also investigated. Finally, the inhibition of signaling molecules by GLSP was detected through immunoassays. Results: GLSP was determined to be composed of galactose. GLSP could alleviate allergy symptoms, effectively reduce shrimp-specific antibodies, decrease the levels of histamine, suppress T cell activation and inhibit the function of allergic cells as well as the allergic molecules in those cells called Syk and p38 mitogen-activated protein kinases (MAPK). Conclusion: Immunosuppression as well as the reduction in the levels of Syk and p38 MAPK may contribute to the ability of GLSP to suppress the symptoms of food allergy. The sulfate of GLSP may play an important role in the anti-allergic effect.

Technical Abstract: Polysaccharides from marine sources offer diverse therapeutic functions due to their multifarious biological nature. Polysaccharide from Gracilaria lemaneiformis possesses various bioactive functions, but its anti-allergic activity remains incompletely defined. Objective: This study aimed to extract and analyze sulfated polysaccharide from Gracilaria lemaneiformis (GLSP), investigate the effects of GLSP on the anti-allergic activity in both animal and cell models, and explore its anti-allergic mechanisms. Methods: GLSP was obtained by water extraction, ethyl alcohol deposition, and column chromatography. Tropomyosin (TM)-sensitized mice were treated with GLSP intragastrically for preventive? and treatment groups. The effects of GLSP on the function of IgE-mediated RBL-2H3 and the activation of KU812 cell lines were also investigated. Finally, the inhibition of signaling molecules by GLSP was detected through Western blot and Proteome assays. Results: GLSP was a 152,481 Da sulfated polysaccharose composed of galactose. GLSP could alleviate allergy symptoms, effectively reduce TM-specific IgE and IgG1, decrease the levels of histamine and mMCP-1, suppress Th2 cell polarization, and promote the function of regulatory T cells in mice. In addition, GLSP had the ability to inhibit the function of RBL-2H3 cells. And the the sulfate of GLSP inhibited degranulation. Meanwhile, the expression of CD63 and CD203c were reduced by GLSP in activated KU812 cells. GLSP inhibited the activation of KU812 via suppressing Syk and p38 mitogen-activated protein kinases (MAPK). Conclusion: Immunosuppression as well as the reduction in the levels of Syk and p38 MAPK may contribute to the ability of GLSP to suppress the symptoms of food allergy. The sulfate of GLSP may play an important role in the anti-allergic effect.