RESUMO
Crude exopolysaccharides from extracellular polymeric substances produced by the marine bacterium Bacillus sp. H5 were fractionated using DEAE-Sepharose FF and Sephadex G-75 chromatography. The high molecular weight fraction (89.0 kD) from the neutral fraction was designated EPS5SH; it contained mannose, glucosamine, glucose, and galactose in a molar ratio of 1.00: 0.02: 0.07: 0.02. Infra-red, gas chromatography-mass spectrometry, electrospray ionisation-tandem mass spectrometry analysis and nuclear magnetic resonance revealed EPS5SH was a mannan with α-(1 â 4)-Manp, α-(1 â 2)-Manp, α-(1 â 4, 6)-Manp and ß-terminal-Manp. Preliminary in vitro experiments revealed that EPS5SH significantly upregulated nitric oxide synthesis and release of pro-inflammatory factors in murine macrophage RAW264.7 cells. Western blot experiments verified the immunostimulatory effects of EPS5SH through the modulation of the NF-κB and MAPK signalling pathways. In conclusion, EPS5SH was a novel immunostimulatory mannan.
Assuntos
Bacillus/química , Fatores Imunológicos/farmacologia , Polissacarídeos/isolamento & purificação , Animais , Morte Celular/efeitos dos fármacos , DNA Ribossômico/genética , Cromatografia Gasosa-Espectrometria de Massas , Lipopolissacarídeos/química , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Espectroscopia de Ressonância Magnética , Metilação , Camundongos , Peso Molecular , Monossacarídeos/análise , NF-kappa B/metabolismo , Células RAW 264.7 , Espectroscopia de Infravermelho com Transformada de Fourier , Receptor 4 Toll-Like/metabolismoRESUMO
Microbial polysaccharides from extreme environments, such as cold seeps and hydrothermal vents, usually exhibit novel structural features and diverse biological activities. In this study, an exopolysaccharide (EPS2E1) was isolated from cold-seep bacterium Halomonas sp. 2E1 and its immune-enhancing activity was evaluated. The total sugar content and protein content were determined as 83.1% and 7.9%, respectively. EPS2E1 contained mannose and glucose with the molar ratio of 3.76: 1. The molecular weight was determined to be 47.0 kDa. Structural analysis indicated that EPS2E1 was highly branched, the backbone mainly consisted of â2)-Man-(α-1â and â2, 6)-Man-(α-1â with the ratio of 2.45: 1.00. The chain also contained â4)-Glc-(α-1â, â6)-Man-(α-1â and â3)-Glc-(ß-1â. EPS2E1 could significantly increase the production of NO, COX-2, TNF-α, IL-1ß and IL-6 by activating the MAPK and NF-κB pathways on RAW264.7 macrophages. EPS2E1 exhibits the potential to be an immunopotentiator in the near future.
Assuntos
Halomonas/classificação , Macrófagos/citologia , Polissacarídeos Bacterianos/química , Polissacarídeos Bacterianos/farmacologia , Animais , Sequência de Carboidratos , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Fermentação , Regulação da Expressão Gênica/efeitos dos fármacos , Halomonas/isolamento & purificação , Halomonas/metabolismo , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Macrófagos/efeitos dos fármacos , Macrófagos/imunologia , Camundongos , Peso Molecular , NF-kappa B/metabolismo , Óxido Nítrico/metabolismo , Filogenia , Polissacarídeos Bacterianos/isolamento & purificação , Células RAW 264.7 , RNA Ribossômico 16S/genéticaRESUMO
The prognosis of liver cancer was inferior among tumors. New medicine treatments are urgently needed. In this study, a novel exopolysaccharide EPS364 was purified from Vibrio alginolyticus 364, which was isolated from a deep-sea cold seep of the South China Sea. Further research showed that EPS364 consisted of mannose, glucosamine, gluconic acid, galactosamine and arabinose with a molar ratio of 5:9:3.4:0.5:0.8. The relative molecular weight of EPS364 was 14.8 kDa. Our results further revealed that EPS364 was a ß-linked and phosphorylated polysaccharide. Notably, EPS364 exhibited a significant antitumor activity, with inducing apoptosis, dissipation of the mitochondrial membrane potential (MMP) and generation of reactive oxygen species (ROS) in Huh7.5 liver cancer cells. Proteomic and quantitative real-time PCR analyses indicated that EPS364 inhibited cancer cell growth and adhesion via targeting the FGF19-FGFR4 signaling pathway. These findings suggest that EPS364 is a promising antitumor agent for pharmacotherapy.
Assuntos
Antineoplásicos/farmacologia , Adesão Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Neoplasias Hepáticas/tratamento farmacológico , Polissacarídeos Bacterianos/farmacologia , Vibrio alginolyticus/metabolismo , Antineoplásicos/isolamento & purificação , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Fatores de Crescimento de Fibroblastos/metabolismo , Humanos , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/patologia , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Estrutura Molecular , Polissacarídeos Bacterianos/isolamento & purificação , Espécies Reativas de Oxigênio/metabolismo , Receptor Tipo 4 de Fator de Crescimento de Fibroblastos/metabolismo , Transdução de Sinais , Relação Estrutura-AtividadeRESUMO
Sea urchin possesses both high nutritional and medicinal value. It contains diverse biological active polysaccharides. But there are few studies on its glycogen. In the current study, a glucan (MSGA) was separated from Strongylocentyotus internedius and purified by ion exchange and gel filtration column. Chemical analysis revealed that MSGA with 2.65 × 107 Da is made up entirely of glucose. The analysis of methylation, NMR and mass spectrum demonstrated that MSGA is a highly branched glycogen with α-(1â4) linked gluconic backbone and branched at C-6 (one branch per five residues). In addition, MSGA showed good in vitro immunostimulatory activity via NF-κB and MAPKs pathways. It is considered that high degree of branching is necessary for its activity. However, the relationship between structure and immunostimulatory activity of natural glycogens is difficult to elucidate because the difference in their structural properties. Therefore, much more research is needed in this area.
