Polysaccharides from Epimedium koreanum Nakai with immunomodulatory activity and inhibitory effect on tumor growth in LLC-bearing mice
Graphical abstract
Introduction
Lung cancer remains the leading cause of cancer-related death worldwide with a 5-year survival rate of less than 15% (Wood et al., 2015). Emerging evidence highlight that immunological responses take an important part in the pathogenesis of lung carcinoma (Carpagnano et al., 2011, Ronan et al., 2010). Recent studies indicated polysaccharides derived from fungi and plant, especially from traditional Chinese medicine, have potent therapeutic properties and relatively nontoxic effects (Vannucci et al., 2013). Ginseng polysaccharide, Ganoderma polysaccharides, Pachymaran, for example, which were all obtained from Chinese herb materials, have exhibited extraordinary bioactivities such as antioxidant, immunomodulation, and anti-tumor (Zhou et al., 2014a, Ferreira et al., 2015, Chihara et al., 1970). So polysaccharides show a wide application prospect acting as immune stimulants in the prevention and therapy of tumor.
Epimedium koreanum Nakai is documented as tonic herbal in China for over a thousand years, meaning it has the potential to enhance the body's immunity as a whole according to the theory of traditional Chinese medicine (Cho et al., 2015). Studies have been reported that crude polysaccharide from E. koreanum Nakai (EPS) possessed strong DPPH radicals scavenging properties and could activate macrophages, enhance NK cell activity as well (Ma et al., 2011, Chen et al., 2012). However, information about immunological regulation of its polysaccharides is limited and the reports of purification, characterization of polysaccharides have remained less.
Therefore, in this context, EPS was previously isolated and purified by a series of separation technologies. Then we evaluated EPS using immunological experiments in vitro. Treatment group with EPS remarkably promoted maturation as well as Ag presentation activity of DCs. In addition, EPS could also significantly enhance the levels of immunomodulatory cytokines secreted by peritoneal macrophages and T cells. Furthermore, investigation in LLC-bearing C57BL/6 mice suggested EPS reduced tumor burden by exerting strong immunomodulatory effects. The aim of our study is to provide the scientific basis and develop a novel molecule which may serve as a supplementary compound for treatment of lung cancer.
Section snippets
Materials and reagents
The dried leaves of E. koreanum Nakai were collected from Dong-bei (China) and authenticated by professor Bao-lin Guo from Chinese Academy of Medical Sciences medicine. Anti-mouse mAbs CD40-FITC, CD80-FITC, CD86-FITC, MHC-II-FITC, CD11c-APC, F4/80-PE and appropriately labeled isotype controls were offered by Biolegend (San Diego, CA) and Golgiplug were purchased from BD Pharmingen (San Diego, CA). Anti-mouse cytokine mAbs IL-6-PE, TNF-α-PE IL-12-PE, and IFN-γ-PE and isotype-PE were purchased
A homogenous polysaccharide obtained from EPS
The purification steps of crude polysaccharide were as shown in Fig. 1.A. Crude polysaccharide was performed on a DEAE cellulose-52 anion exchange column to obtain four fractions (Fig. 1. B). However, due to the strongest immue activities (Supplementary data), F0.3 was selected to be further purified using a column of Sephadex G-100. On gel filtration chromatography, EPS showed a symmetrical peak (Fig. 1. C), indicating that it is a homogenous polysaccharide. The carbohydrate content of EPS was
Conclusions
Polysaccharide is one of the bioactive components of Epimedium koreanum Nakai. However, EPS lacks the research on tumor-inhibition through regulation in immune responses, obstructing the progress of Epimedium koreanum Nakai as a traditional immune-enhancing herb (Cheng et al., 2013b). We thus carried out this research to explore the possible mechanism for its immune activities to treat cancer.
Firstly, a novel fraction polysaccharide EPS was successfully isolated and purified from Epimedium
Acknowledgements
This work was supported by the National Natural Science Foundation of China (No. 81403121 and 81503265), State Administration of Traditional Chinese Medicine of PRC, base construction research Program( JDZX2015195) and the government study abroad scholarship program in jiangsu province. In addition, I would like to express our gratitude towards Jun Yan and Chuanlin Ding, professors from University of Louisville School of Medicine, for their professional instructions.
References (40)
- et al.
Antitumor and immunomodulatory activities of a polysaccharide from Artemisia argyi
Carbohydr. Polym.
(2013) - et al.
New method for quantitative determination of uronic acid
Anal. Biochem
(1973) - et al.
Purification, characterization and anti-proliferation activities ofpolysaccharides extracted from Viscum coloratum (Kom.) Nakai
Carbohydr. Polym.
(2016) - et al.
Ultrasound complex enzymes assisted extraction and biochemical activities of polysaccharides from Epimedium leaves
Process Biochem.
(2012) - et al.
Structural characterization and antioxidant activities of polysaccharides extracted from Epimedium acuminatum
Carbohydr. Polym.
(2013) - et al.
Extraction, antioxidant and antimicrobial activities of Epimedium acuminatum Franch. Polysaccharide
Carbohydr. Polym.
(2013) - et al.
Targeting of antigens to B cells augments antigen-specific Tcell responses and breaks immune tolerance to tumor-associated antigen MUC1
Blood
(2008) - et al.
The preparation optimization and immune effect of epimedium polysacchaide-propolis flavone liposome
Carbohydr. Polym.
(2013) - et al.
Chemical features of Ganoderma polysaccharides with antioxidant, antitumor and antimicrobial activities
Phytochemistry
(2015) - et al.
Extracts from Citrus unshiu promote immune-mediated inhibition of tumor growth in a murine renal cell carcinoma model
J. Ethnopharmacol.
(2011)