ABSTRACT
The immunoregulatory activity of sulfated polysaccharide from Porphyra haitanensis (PHPS) was investigated in a RAW264.7 macrophages cell model and a BALB/c murine model. The subpopulation of dendritic cells (DCs) and regulatory T cells (Tregs) from PHPS-treated mice splenocytes were also measured by flow cytometry. Consistent with previous reports, we showed that PHPS increased the phagocytosis of RAW264.7 macrophages, and enhanced the secretion of interleukin (IL)-6, IL-10 and tumor necrosis factor-α (TNF-α). Meanwhile, PHPS induced the production of nitric oxide via the Jun N-terminal kinase (JNK) and the Janus kinase (JAK2) signaling pathways in RAW264.7 macrophages. Furthermore, PHPS promoted the proliferation of mice lymphocytes, inducing the generation of TNF-α and IL-10 in vivo, as well as the subpopulation of CD4+ splenic T lymphocytes, DCs, and Tregs. These results indicated that PHPS plays key roles in immunoregulation and may be apply to develop new health foods.
Subject(s)
Macrophages/drug effects , Polysaccharides/pharmacology , Porphyra/chemistry , Animals , Cytokines/immunology , Dendritic Cells/drug effects , Dendritic Cells/immunology , Macrophages/immunology , Mice , Mice, Inbred BALB C , RAW 264.7 Cells , Sulfates , T-Lymphocytes, Regulatory/drug effects , T-Lymphocytes, Regulatory/immunologyABSTRACT
Polysaccharides from Gracilaria lemaneiformis in particular possess various bioactive functions, but their antiallergic activity remains incompletely defined. Sulfated polysaccharide from Gracilaria lemaneiformis (GLSP) was obtained by water extraction and ethanol precipitation followed by column chromatography. BALB/c mice, RBL-2H3, and KU812 cells were used for verifying the anti food allergic activity of GLSP. According to the results of mice experiment, GLSP was able to alleviate allergy symptoms, to reduce TM-specific IgE and IgG1, to suppress Th2 cell polarization, and to promote the function of regulatory T (Treg) cells. In addition, GLSP had the ability to inhibit the function of RBL-2H3 cells. Furthermore, GLSP inhibited the activation of KU812 via suppression of p38 mitogen-activated protein kinase (MAPK). In conclusion, immunosuppression as well as the reduction in the level of p38 MAPK may contribute to GLSP's putative activity against food allergy. GLSP may be used as a functional food component for allergic patients.
Subject(s)
Anti-Allergic Agents/administration & dosage , Food Hypersensitivity/drug therapy , Gracilaria/chemistry , Plant Extracts/administration & dosage , Polysaccharides/administration & dosage , p38 Mitogen-Activated Protein Kinases/immunology , Animals , Anti-Allergic Agents/chemistry , Female , Food Hypersensitivity/genetics , Food Hypersensitivity/immunology , Humans , Immunosuppression Therapy , Mast Cells/drug effects , Mast Cells/immunology , Mice , Mice, Inbred BALB C , Plant Extracts/chemistry , Polysaccharides/chemistry , Rats , Seaweed/chemistry , Th2 Cells/drug effects , Th2 Cells/immunology , p38 Mitogen-Activated Protein Kinases/geneticsABSTRACT
Glucose-6-phosphate isomerase (GPI) (EC 5.3.1.9) can act as a myofibril-bound serine proteinase (MBSP) inhibitor (MBSPI) in fish. In order to better understand the biological information of the GPI and its functional domain for inhibiting MBSP, the cDNA of GPI was cloned from crucian carp (Carassius carassius) with RT-PCR, nested-PCR and 3'-RACE. The result of sequencing showed that the GPI cDNA had an open reading frame of 1662bp encoding 553 amino acid residues. After constructing and comparing the three-dimensional structures of GPI and MBSP, the middle fragment of crucian carp GPI (GPI-M) was predicted as a functional domain for inhibiting MBSP. Then the crucian carp GPI-M gene was cloned and expressed in Escherichia coli. SDS-polyacrylamide gel electrophoresis (SDS-PAGE) showed that the recombinant GPI-M (rGPI-M) with molecular mass of approximately 21kDa in the form of inclusion bodies. The rGPI-M was obtained at an electrophoresis level purity of approximately 95% after denaturation and dialysis renaturation.