• Title/Summary/Keyword: sialic acid

Search Result 123, Processing Time 0.027 seconds

Anti-inflammatory Effects and Its Mechanisms of NANA (N-Acylneuraminic Acid) Isolated from Glycomacropeptide (유청단백질 Glycomacropeptide에서 분리한 NANA의 안전성 및 염증저하 메카니즘 구명 연구)

  • Kim, Min-Ho;Kim, Jae-Hong;Lee, Yun-Kyoung;Kim, Wan-Sik;Kim, Hee-Kyoung
    • Journal of Dairy Science and Biotechnology
    • /
    • v.29 no.2
    • /
    • pp.17-23
    • /
    • 2011
  • The focus of this study was to clarify the relation between the nitric oxide (NO) production and cytokine expression including tumor necrosis factor-${\alpha}$ (TNF) and interleukin-6 (IL-6), and also investigated the effect of G-NANA (N-acylneuraminic acid isolates from glycomacropeptide) or S-NANA (Synthetic N-acylneuraminic acid) on LPS stimuli from RAW264.7 cell. The NANA is the predominant sialic acid found in mammalian cells and G-NANA is isolation of GMP (GMP is a valuable bioactive peptide with a varying degree of glycosylation including sialic acid). The lipopolysaccharide (LPS) of Gram-negative bacteria induces the expression of cytokines and potent inducers of inflammatory cytokines such as TNF-${\alpha}$ and IL-6. In this experiment, upon stimulation with increasing concentrations of chitosan, the LPS-stimulated TNF-${\alpha}$ and IL-6 secretion was significantly recovered with in the incubation media of RAW264.7 cells. Consistently, RT-PCR with mRNA and immunoblot analysis with anti-cytokine antiserum including TNF-${\alpha}$ and IL-6 showed that the amount of TNF-${\alpha}$ and IL-6 secretion in the incubation media recovered with the concentration of chitosan. The LPS-stimulated NO secretion was significantly recovered with in the 6 and 12 h incubation media of RAW264.7 cells, too. The recovery effect of G-NANA on IL-6 and NO secretion may be induced via the stimulus of TNF-${\alpha}$ in RAW264.7 cell. These results once again suggest that G-NANA may have the anti-inflammatory effect via the stimulus of TNF-${\alpha}$ in the LPS-stimulated inflammation in RAW264.7 cells.

  • PDF

Purification and Characterization of Hemagglutinating Protein from Rhizome of Alisma orientale (택사(Alismatis Rhizoma) Hemagglutinating Protein의 정제와 특성)

  • 박종옥;김경순;선우근옥
    • Journal of the Korean Society of Food Science and Nutrition
    • /
    • v.24 no.4
    • /
    • pp.587-593
    • /
    • 1995
  • Lectin was purified by using $(NH_4)_2SO_4$, DEAE-cellulose ion-exchange chromatography and Sephadex G-150 column chromatography from Alismatis Rhizoma(AR). The specific activity of AR lectin was 50, 441units/mg, and purification folds were 114. The AR lectin agglutinated human erythrocytes of all types(A, B, O, AB). The molecular weight of AR lectin was estimated about 90, 500 daltons by gel filtration and each subunits were 42,000, 27,000 and 22,500 daltons on SDS-PAGE respectively. The hemagglutinating activity of the lectin was inhibited by sialic acid, glucose, ribose, galactose, sucrose, and lactose. It was also inhibited by cations such as $Hg^{++},\;Fe^{++},\;Cu^{++}\;and\;Pb^{++}$.

  • PDF

Lysyl-tRNA Synthetase Inhibits Various Shear Stress-stimulated Signaling Pathways in Endothelial Cells

  • Park, Heon-Yong
    • Proceedings of the Korean Society of Applied Pharmacology
    • /
    • 2008.04a
    • /
    • pp.103-115
    • /
    • 2008
  • Hemodynamic shear stress, the dragging force generated by blood flow, is known as an anti-atherogenic factor. We tested whether lysyl-tRNA synthetase (KRS) will be utilized as an agent controlling shear-sensing systems. KRS was previously known to be secreted as a pro-inflammatory agent. Here we found that KRS inhibited various shear-stimulated signaling pathways. We further found that KRS binds to detergent-resistant membrane (DRM), indicating that KRS binding molecules exist in DRM, specialized regions of the plasma membrane. DRM plays important roles in a variety of cellular processes and consists of gangliosides, signaling molecules and cytoskeletons. We then determined that KRS was colocalized with integrins ${\alpha}4$, ${\alpha}5$ and $av{\beta}3$. In addition, KRS was shown to be associated with sialic acid, existing at the end of gangliosides. Interestingly, the adherent effect of KRS was inhibited by pretreatment with sialic acid. Moreover, treatment of endothelial cells with neuraminidase appeared to inhibit both the KRS adhesion to endothelial cells and shear-stimulated signaling. In conclusion, KRS is likely to be utilized as a vascular regulator.

  • PDF

Sialylated oligosaccharide analyses using high-performance liquid chromatography with a fluorescence detector

  • Cho, Due-Hyeon;Ryu, Chang-Soo;Park, Jee-Hun;Kim, Ha-Hyung
    • Proceedings of the PSK Conference
    • /
    • 2003.04a
    • /
    • pp.316.1-316.1
    • /
    • 2003
  • N-acetylneuraminic acid is one of the major derivatives of sialic acid. is widely distributed in mammalian cells as the ${\alpha}$2-3- or ${\alpha}$2-6-linked nonreducing terminal residue of oligosaccharide chains of glycoconjugates, and plays important structural and functional roles at the cell membrane surface. The analysis of sialylated glycoproteins is an important part of glycoprotein characterization, especially because sialylation or desialylation in oligosaccharides often causes dramatic changes in the function of glycoproteins. (omitted)

  • PDF

Effect of Clonorchis sinensis Excretory-secretory Product on the Cultured SD Rat Bile Duct Fibroblast (배양된 흰쥐 담관 섬유모세포에 대한 간흡충 분비배설 물질의 영향)

  • Kwon, Jung-Nam;Min, Byoung-Hoon;Lee, Haeng-Sook;Kim, Soo-Jin;Joo, Kyoung-Hwan
    • Applied Microscopy
    • /
    • v.39 no.2
    • /
    • pp.117-124
    • /
    • 2009
  • Clonorchis sinensis is the most important widely distributed parasite of the human bile duct in East Asia and the most prevalent parasitic helminth in Korea. The prevalence rate of human clonorchiasis has remained at about 2.9% in Korea. C. sinensis induces dilatation of the duct, hyperplasia of the mucosa, metaplasia or neoplasia of the mucosal epithelium, periductal inflammation and fibrosis, and thickening of the ductal wall. Fibroblast are the most common cells in connective tissue and are responsible for the synthesis of extracellular matrix components. The fibrosis associated with chronic inflammation and injury may also contribute to cholangiocarcinoma pathogenesis, particularly through an increase in extracellular matrix components, which participate in the regulation of bile duct differentiation during development. In this study, ultrastructural changes, the distribution of lectin receptors and actin protein in cultured SD rat bile duct fibroblast after infection of C. sinensis were observed. Experimental group had been divided into four groups: normal bile duct fibroblast cultured in basal media (G1); C. sinensis infected bile duct fibroblast cultured in basal media (G2); normal bile duct fibroblast cultured in basal media containing excretory-secretory product (ESP) (G1-1); C. sinensis infected bile duct fibroblast cultured in basal media containing ESP (G2-1). Overall, once a host is infected by C. sinensis, it affects the host to the extent that sialic acid of ductal fibroblast is increased. Number of cytoplasmic process of SD rat bile duct fibroblast was increased. Actin protein and sialic acid were located in cell surface. Fibroblast induced by C. sinensis was not recovered to normal fibroblast. The cytoplasm bulk and cytoplasmic process were increased whereas the growth rate of the fibroblast of infected SD rat was reduced rather than that of normal fibroblast. In result, it inhibits fibroblast proliferation and increases actin protein on fibroblast cytoplasm, and so causes fibroblast metamorphosis and cellular mutation.