• Title/Summary/Keyword: sialic acid

Search Result 123, Processing Time 0.033 seconds

Analysis of Erythropoietin Glycoform Produced by Recombinant CHO Cells Using the Lectin-Blotting Technique

  • Chang, Kern-Hee;Kim, Kyung-Soo;Kim, Jung-Hoe
    • Biotechnology and Bioprocess Engineering:BBE
    • /
    • v.3 no.1
    • /
    • pp.40-43
    • /
    • 1998
  • The glycosylation pattern of Erythropoietin (EPO), produced by recombinant CHO cells, was studied using the simple and rapid technique of 'Lectin-blotting'. In this experiment we used three different kinds of lectins, MAA(Maackia amurensis agglutinine), RCA(Ricinus communis agglutinine), and DSA(Datura stramonium agglutinine), which bind to the terminal sialic acid, galactose, and the N-acetyllactosamine chain respectively. The lectin-blotting technique was used to analyze the carbohydrate structure of EPO produced in the presence of two physiologically active chemical compounds, ammonium and chloroquine. The effect of the ammonium ion on the glycosylation of EPO was studied because it accumulated in the medium mainly as a by-product of glutamine matabolism. Ammonium chloride significantly inhibited the sialylation of the terminal galactose residue at concentrations of 8mM or more. Chloroquine, a potent inhibitor of glycosylation, inhibited terminal sialylation at concentrations of 100 and 200 $\mu$M, and at a concentration of 300 $\mu$M, also inhibited Nacetyllactosamine chain synthesis.

  • PDF

Inhibition of Helicobacter pylori Adhesion by Acidic Polysaccharide Isolated from Artemisia capillaris

  • Woo, Jeung-S.;Ha, Byung-H.;Kim, Tae-G.;Lim, Yoon-Gho;Kim, Kyung-H.
    • Journal of Microbiology and Biotechnology
    • /
    • v.13 no.6
    • /
    • pp.853-858
    • /
    • 2003
  • Helicobacter pylori specifically adhere to host cells through a number of putative receptors and ligands, mainly based on carbohydrate-protein interactions. Polysaccharide fractions isolated from the leaves of Artemisia capillaris showed different inhibitory activities against H. pylori adhesion by using hemagglutination assay. Among these fractions, an acidic polysaccharide fraction FlA showed highly effective inhibitory activity, and its minimum inhibition concentration was 0.63 mg/ml. The inhibition results by the hemagglutination assay were consistent with those obtained by the enzymelinked glycosorbent assay, which was developed by the conjugation of horseradish peroxidase with fetuin, a sialic acid-containing glycoprotein which was specific to H. pylori adhesion. FlA contained the highest carbohydrate content among polysaccharide fractions, and no protein was detectable when further purified by gel filtration FPLC. Sugar composition analysis using GC revealed the highest amount of galacturonic acid among sugars, which suggests that FlA contains essentially acidic polysaccharides. Our data suggest that acidic polysaccharides may play an important role in the inhibition of H. pylori adhesion to host cells.

Inhibition of Metastatic Lung Cancer in C57BL/6 Mice by Marine Mangrove Rhizophora apiculata

  • Prabhu, V. Vinod;Guruvayoorappan, C.
    • Asian Pacific Journal of Cancer Prevention
    • /
    • v.14 no.3
    • /
    • pp.1833-1840
    • /
    • 2013
  • Metastasis is one of the hallmarks of malignant neoplasms and is the leading cause of death in many cancer patients. A major challenge in cancer treatment is to find better ways to specifically target tumor metastasis. In this study, the anti-metastatic potential of the methanolic extract of Rhizophora apiculata (R.apiculata) was evaluated using the B16F-10 melanoma induced lung metastasis model in C57BL/6 mice. Metastasis was induced in C57BL/6 mice by injecting highly metastatic B16F-10 melanoma cells through the lateral tail vein. Simultaneous treatment with R.apiculata extract (10 mg/kg b.wt (intraperitoneal) significantly (p<0.01) inhibited pulmonary tumor nodule formation (41.1 %) and also increased the life span (survival rate) 107.3 % of metastatic tumor bearing animals. The administration of R.apiculata extract significantly (p<0.01) reduced biochemical parameters such as lung collagen hydroxyproline, hexosamine, uronic acid content, serum nitric oxide (NO), ${\gamma}$-glutamyl transpeptidase (GGT) and sialic acid levels when compared to metastasis controls. These results correlated with lung histopathology analysis of R.apiculata extract treated mice showing reduction in lung metastasis and tumor masses. Taken together, our findings support that R.apiculata extract could be used as a potential anti-metastasis agent against lung cancer.

Effect of Luteolin on the Levels of Glycoproteins During Azoxymethane-induced Colon Carcinogenesis in Mice

  • Pandurangan, Ashok Kumar;Dharmalingam, Prakash;Sadagopan, Suresh Kumar Ananda;Ganapasam, Sudhandiran
    • Asian Pacific Journal of Cancer Prevention
    • /
    • v.13 no.4
    • /
    • pp.1569-1573
    • /
    • 2012
  • Luteolin (LUT), a bioflavonoid has been used as a chemopreventive agent world-wide against chemically induced cancer. Hence we designed an experiment to assess chemopreventive action of LUT on lipid peroxidation (LPO) and glycoconjugates in azoxymethane (AOM)-induced colon carcinogenesis. Colon cancer was induced by 15 mg/body kg. body weight of AOM and administration of LUT (at the dose of 1.2 mg/kg. body weight) was till end of the study. Analysis of lipid peroxidative end products such as protein carbonyl (PC), malonadehyde (MDA) and conjucated dienes (CD) demonstrated significant increase in in AOM-induced animals with reduction by LUT (p<0.05). Increased levels of glycoconjugates such as hexose, hexosamine, sialic acid, fucose and mucoprotein were analyzed in serum and colon tissues examined histopathologically by periodic acid Schiff's (PAS) staining were also reversed by LUT l(p<0.05). The secondary marker of colon cancer mucin depleted foci (MDF) was assessed in control and experimental group of animals. A characteristic increase of MDF was observed in AOM-induced colon cancer animals. Treatment with LUT decreased the incidence of MDF. These results suggest that LUT alters the expression of glycoconjugates and suppress colon cancer. Hence, we speculate that LUT can be used as a chemopreventive agent to treat colon cancer.

Spermatogenic index and hormonal profile in the rats received chromatographic fractions of ethanol extract of Crotalaria juncea L. seeds

  • Malashetty, Vijaykumar B.;Patil, Saraswati B.
    • Advances in Traditional Medicine
    • /
    • v.6 no.2
    • /
    • pp.86-95
    • /
    • 2006
  • The ethanol extract of the Crotalaria juncea seeds, which showed promising antispermatogenic and antiandrogenic activities in albino mice, was taken up further for the isolation of the active fractions present in it. Two fractions that were obtained from thin layer chromatography were subjected for testing to know their antispermatogenic and antiandrogenic activities. After preliminary trials the fraction I showed maximum antifertility activity at the dose level of 200 mg/kg body weight when administered orally to the rats for 50 days. The fraction I was found to affect spermatogenesis as well as the endocrine functions of the testis as indicated by gravimetric, histopathological and biochemical changes. Further this fraction has caused degenerative changes in the seminiferous tubules and Leydig cells of the testis. The accessory reproductive organs like epididymis, seminal vesicles, vas deferens, prostrate, Cowper's gland and Levator Ani muscle showed significant malfunction. Cauda epididymal sperm count and sperm motility were reduced significantly. The treatment has also resulted in increase in the cholesterol level and alkaline phosphatase activity, and decrease in protein, glycogen, sialic acid contents and acid phosphatase activity in testis. It is noteworthy that RIA studies have shown significant reduction in serum FSH, LH and testosterone. Scanning electron microscopic observations revealed abnormalities in sperm structure.

Hematopoietic effect of deer antler extract fermented by Bacillus subtilis on murine marrow cells

  • Park, Yooheon;Choi, Hyeon-Son;Lee, Hyun-Sun;Suh, Hyung Joo
    • Nutrition Research and Practice
    • /
    • v.9 no.5
    • /
    • pp.451-458
    • /
    • 2015
  • BACKGROUND/OBJECTIVES: We examined the chemical composition and the effect of fermented deer antler on hematopoietic factors in bone marrow cells. MATERIALS/METHODS: For the preparation of fermented deer antler extract (FAB), fermentation was carried out using Bacillus subtilis at $30^{\circ}C$ for 7 days. The hematopoietic effect of FAB was investigated hematopoietic factors in marrow cells. RESULTS: The contents of total sugar, sulfated glycosaminoglycans, and uronic acid and the dry weight gradually increased with fermentation time. The sialic acid content (from 0.14 mg/mL to 0.54 mg/mL) was the highest on the 4th day of fermentation after which it decreased. The proliferating activity of bone marrow cells increased with fermentation times. The levels of various hematopoietic growth factors were determined to verify the beneficial effect of deer antler extract fermented by B. subtilis on hematopoiesis. FAB increased the number of stem cell factors and granulocyte colony-stimulating factor in bone marrow cells. In addition, FAB augmented the burst-forming unit erythroid and total colonies in splenocyte-conditioned medium compared with non-fermented antler extract (NFA). However, FAB did not affect the mRNA levels of erythropoietin, an important factor for erythropoiesis. CONCLUSIONS: FAB, like NFA, did not directly affect hematopoiesis, but contributed to hematopoiesis by stimulating the production of hematopoietic factors.

The Effect of Pretreatment with Various Mutagens on Glycoconjugates of Plasma Membrane in HeLa Cells (HeLa 세포에서 원형질 막의 glycoconjugate에 대한 수종 돌연변이원의 전처리 효과)

  • Lee, Jong-Hwa;Oh, Kyu-Seon;Lee, Dong-Wook;Shin, Eun-Joo;Um, Kyung-Il
    • Environmental Mutagens and Carcinogens
    • /
    • v.18 no.2
    • /
    • pp.116-122
    • /
    • 1998
  • The present investigation has been performed to elucidate the effect of pretreatment with low dose of ultraviolet radiation (UV), ethyl methansulfonate (EMS), and bleomycin (BLM) on cell survival and lectin-binding glycoconjugates of plasma membrane in HeLa cells treated with mutagen. The percentage of survival of cells pretreated with 1 mM EMS following treatment with 10 mM EMS was higher than that of cells treated with 10 mM EMS alone. Wheat germ agglutinin (WGA) staining intensity of cells pretreated with 1 mM EMS and subsequently treated with 10 mM EMS was stronger than that of cells treated with 10 mM EMS alone. But, succinylated wheat germ agglutinin (sWGA) staining intensity of cells pretreated with 1 mM EMS and subsequently treated with 10 mM EMS was similar to that of cells treated with 10 mM EMS alone. These results suggest that the acquired resistance to EMS is related to the glycoconjugates containing sialic acid of plasma membrane involved in multidrug resistance or adaptive response in HeLa cells.

  • PDF

Ultrastructural Change of the Bile Duct Fibroblast at Infected Rat with Clonorchis sinensis (간흡충에 감염된 실험쥐 담관 섬유모세포의 미세구조적 변화)

  • Kim, Soo-Jin;Min, Byoung-Hoon
    • Applied Microscopy
    • /
    • v.34 no.2
    • /
    • pp.121-130
    • /
    • 2004
  • In this study, ultrastructural change of the bile duct fibroblast at infected rat with Clonorchis sinensis, and the distribution of lectin receptors and actin protein in cultured bile duct infected with Clonorchis sinensis. It explored using colloidal gold label complex with lectin WGA purified from wheat germ (Triticum vulgaris) and anti actin antibody purified actin (43 kDa) isolated from chicken back muscle. The lectin WGA with protein A gold complex labeled sections of the cultured fibroblast revealed gold particles specifically distributed on the multi vesicular form Golgi complex and cell surface of the fibroblast. The actin antibody with protein A gold complex labeled sections of the cultured fibroblast revealed gold particles specifically distributed on the cytoplasm of the fibroblast. Labeling of cultured fibroblast in rat bile duct infected with Clonorchis sinensis was then quantified and compared to that of cultured Fibroblast in Rat Bile duct. These results indicate that lectin WGA receptors are located in the multi vesicular form Golgi complex in the cytoplasm to the cytoplasmic process of the Rat bile duct fibroblast infected with Clonorchis sinensis. Therefore, the GlcNAc and NeuNac regions on the cell surface and cytoplasmic process appear to be functionally associated with cell-recognition and protection from other cell of the tissue, and linked with secretion and exocytosis of the fibroblst cytoplasm. GlcNAc and NeuNAc product in the multi vesicular form Golgi complex then it is transported to cell surface. Actin protein is many appears that infected fibroblast rather than normal fibroblast. The fibroblast of infected with Clonorchis sinensis are against of the physical and chemical stimulation. Then development of cytoplasmic process is relative some stimulation.

Separation of Glycomacropeptide from Bovine and Caprine Milk: Effect of Its Tryptic Hydrolysate on the Inhibition of Platelet Aggregation (Bovine과 Caprine유(乳)로부터 Glycomacropeptide 분리: 트립신 가수분해물의 혈소판응집억제 효과)

  • Kim, Sang-Bum;Ryu, Jin-Soo;Ki, Kwang-Seok;Lee, Wang-Shik;Lee, Hyun-June;Yang, Seung-Hak;Kim, Hyeon-Shup;Choi, Choong-Kuk
    • Journal of agriculture & life science
    • /
    • v.43 no.1
    • /
    • pp.25-33
    • /
    • 2009
  • This study was carried out to isolate and characterize the glycomacropeptide (GMP) prepared from cow's milk and Korean native goat's milk and to examine the effects of their tryptic hydrolysates on inhibition of platelet aggregation in an in vitro experiment. The GMP derived from Holstein, Korean native goat and Hanwoo migrated at 20 KDa. Sialic acid contents in skim milk of Holstein, Korean native goat and Hanwoo were $36.86{\pm}2.36$, $37.98{\pm}1.27$ and $31.19{\pm}1.87{\mu}g/mg$, respectively. Tyrosine was detected in both bovine and caprine GMP. The in vitro inhibition rate of platelet agregation by tryptic hydrolysates of Holstein, Korean native goat and Hanwoo GMP were 4.02, 5.51 and 12.77%, respectively at reaction time 30 seconds. The inhibition of platelet aggregation by tryptic hydrolysates of bovine and caprine GMP are increased with increasing reaction time. The platelets staining revealed higher counts of platelets after the addition of GMP hydrolysates; however addition of ADP reduced the platelet count within 30 seconds and the platelets were not detected after 120 seconds. The results of this study indicate that tryptic hydrolysates of bovine and caprine GMP contain some small peptides with platelet aggregation inhibition properties. Further research on these lines may help prevent platelet aggregation related abnomalities in human.

A Novel Therapeutic Effect of a New Variant of CTLA4-Ig with Four Antennas That Are Terminally Capped with Sialic Acid in the CTLA4 Region

  • Piao, Yongwei;Yun, So Yoon;Kim, Hee Soo;Park, Bo Kyung;Ha, Hae Chan;Fu, Zhicheng;Jang, Ji Min;Back, Moon Jung;Shin, In Chul;Won, Jong Hoon;Kim, Dae Kyong
    • Biomolecules & Therapeutics
    • /
    • v.30 no.6
    • /
    • pp.529-539
    • /
    • 2022
  • Rheumatoid arthritis (RA) is a multifactorial immune-mediated disease, the pathogenesis of which involves different cell types. T-cell activation plays an important role in RA. Therefore, inhibiting T-cell activation is one of the current therapeutic strategies. Cytotoxic T-lymphocyte antigen 4-immunoglobulin (CTLA4-Ig), also known as abatacept, reduces cytokine secretion by inhibiting T-cell activation. To achieve a homeostatic therapeutic effect, CTLA4-Ig has to be administered repeatedly over several weeks, which limits its applicability in RA treatment. To overcome this limitation, we increased the number of sialic acid-capped antennas by genetically engineering the CTLA4 region to increase the therapeutic effect of CTLA4-Ig. N-acetylglucosaminyltransferase (GnT) and α2,6-sialyltransferase (α2,6-ST) were co-overexpressed in Chinese hamster ovary (CHO) cells to generate a highly sialylated CTLA4-Ig fusion protein, named ST6. The therapeutic and immunogenic effects of ST6 and CTLA4-Ig were compared. ST6 dose-dependently decreased paw edema in a mouse model of collagen-induced arthritis and reduced cytokine levels in a co-culture cell assay in a similar manner to CTLA4-Ig. ST6- and CTLA4-Ig-induced T cell-derived cytokines were examined in CD4 T cells isolated from peripheral blood mononuclear cells after cell killing through irradiation followed by flow- and magnetic-bead-assisted separation. Interestingly, compared to CTLA4-Ig, ST6 was substantially less immunogenic and more stable and durable. Our data suggest that ST6 can serve as a novel, less immunogenic therapeutic strategy for patients with RA.