A polysaccharide from Sargassum fusiforme protects against immunosuppression in cyclophosphamide-treated mice

Apios americana Medik flowers polysaccharide (AFP) alleviate Cyclophosphamide-induced immunosuppression in ICR mice

Immunosuppression refers to the suppression of the immune response. The immune function of immunocompromised people is not enough to resist bacterial, viral, fungal and other infections, leading to a series of diseases. A large number of experimental data show that polysaccharide compounds are immune modulators, which can enhance the body immunity with little toxic. Meanwhile, it can reduce the side effects of commonly used immunosuppressants, such as cytotoxicity, decreased ability of the body to fight infection, and inhibition of the reproduction of bone marrow hematopoietic cells. It can be used as oral or injectable drugs. In this study, a purified polysaccharide was primarily extracted from the flowers of Apios americana Medik (AAM), which can improve the immunosuppression induced by cyclophosphamide (CTX). The immunoenhancement effect of AFP was evaluated by measuring the body weight, immune organ index, cytokine secretion and antibody generated levels of CTX-induced mice. Our results showed that AFP could significantly improve the above immune indexes, which indicated AFP could alleviate immunosuppression induced by CTX. The study provided a theoretical basis for the promotion, development and application of AAM as a newly introduced food material.

In Vivo and In Vitro Study of Immunostimulation by Leuconostoc lactis-Produced Gluco-Oligosaccharides

Glycosyltransferase-producing Leuconostoc lactis CCK940 produces CCK- oligosaccharides, gluco-oligosaccharide molecules, using sucrose and maltose as donor and acceptor molecules, respectively. In this study, the immunostimulatory activities of CCK-oligosaccharides on RAW264.7 macrophages and BALB/c mice were evaluated. CCK-oligosaccharides induced the expression of phosphorylated-p38, extracellular-signal-regulated kinase (ERK), and c-Jun N-terminal kinase (JNK) and upregulation of phagocytic activity in RAW264.7 macrophages, suggesting their involvement in mitogen-activated protein kinase (MAPK) signaling pathway and phagocytosis. When CCK-oligosaccharides were administered to mice intraperitoneally injected with cyclophosphamide (CY), spleen indices and expressions of interleukin (IL)-6, IL–10, and tumor necrosis factor-α increased, compared with those in only CY-treated group. These findings suggest that CCK-oligosaccharides can be used as an effective immunostimulating agent.

The antiviral property of Sargassum fusiforme polysaccharide for avian leukosis virus subgroup J in vitro and in vivo

Avian Leukosis Virus Subgroup J (ALV-J) is an oncogenic retrovirus, mainly spread by vertical and horizontal transmission, which have caused severe losses in world poultry industry. Sargassum fusiforme polysaccharide (SFP), a marine algae sulfated polysaccharide, has attracted more attention due to its variously biological activities. In this study, the anti-ALV-J property of SFP was assessed in vivo and in vitro. The results demonstrated that different Mw of SFPs showed virustatic activity to ALV-J in vitro by combining with the virus when ALV-J adsorbed onto the host cells. When treated with SFPs, the ALV-J gene and protein expression reduced clearly and SFP-3 (Molecular weight 9 kDa) had the best antiviral effect. Results in vivo showed that the immunosuppression of the ALV-J infected chickens were relieved by SFP-3. Moreover, SFP-3 obviously inhibit the viral shedding and alleviated the organs damage caused by ALV-J. This study offered a new method for ALV-J treatment and enriched the potential application of SFP.

Oral administration of Urtica macrorrhiza Hand.-Mazz. polysaccharides to protect against cyclophosphamide-induced intestinal immunosuppression

As a strategy to prevent the well-known immunosuppressant effects of cyclophosphamide (CY), the immunomodulatory activity of the polysaccharide isolated from Urtica macrorrhiza Hand.-Mazz. (UMHMPS) was investigated in the present study. The chemical properties of UMHMPS, including total carbohydrates, uronic acid, protein contents, monosaccharide compositions, molecular weight and structural confirmation, were investigated. The immunomodulatory activity of UMHMPS was evaluated using a CY-induced immunosuppression mouse model. The results revealed that UMHMPS, which is composed of rhamnose, gluconic acid, galactose acid, galactose and xylose, exhibited potent immunomodulatory activity and low toxicity in mice. It increased the secretions of secretory immunoglobulin A, interferon (IFN)-γ and interleukin (IL)-4, and maintained the balance of the ratios of IFN-γ/IL-4 and cluster of differentiation (CD)3⁺/CD19⁺ cells in Peyer's patches. Furthermore, it increased the expression of Toll-like receptor (TLR)-4, indicating that TLR4 may be one of the receptors of UMHMPS. Therefore, the present study provides evidence for the potential use of UMHMPS as an immune enhancement drug in chemotherapy.

Water-soluble polysaccharides from Grifola Frondosa fruiting bodies protect against immunosuppression in cyclophosphamide-induced mice via JAK2/STAT3/SOCS signal transduction pathways

Grifola Frondosa, the king of mushrooms, is one of the most valued traditional medicines and has been used as a health food for a long time in China, Japan, and other Asian countries. The present study was designed to evaluate the immune-modulating effects of water-soluble polysaccharides from the Grifola Frondosa fruiting body (GFP) by using mouse peritoneal macrophage and cytoxan (CTX) induced immunosuppression models. Compared with CTX-induced immunosuppressive mice, the spleen and thymus indexes in mice with GFP orally administrated were significantly increased, body weight loss was alleviated, and the natural killer (NK) cytotoxicity and the proliferative activities of lymphocytes were elevated. Furthermore, levels of interleukin-2 (IL-2), interferon-6 (IL-6) and tumor necrosis factor-α (TNF-α) were notably reduced by CTX, while GFP abolished these effects. GFP also effectively increased total antioxidant capacity and superoxidase dismutase, catalase and glutathione peroxidase activities, and inhibited an increase in the malondialdehyde level. Histopathological analysis of spleens revealed the protective effect of GFP against CTX-induced immunosuppression. Western blotting results showed that GFP possessed immunomodulatory activity by up-regulating transcription factors (p-JAK2/JAK2, p-STAT3/STAT3 and SOCS3) in JAK2/STAT3/SOCS signaling pathways. This study suggested that GFP may provide an alternative strategy for lessening chemotherapy-induced immunosuppression.

Immunomodulatory activities of proteins from Astragalus membranaceus waste

BACKGROUND

Astragalus membranaceus is a traditional Chinese medicine that has a long history of medical applications. It is of interest to investigate the functional components of A. membranaceus waste with regard to its development and utilization and increasing resource utilization.

RESULTS

The protein AMWP was isolated from the A. membranaceus waste. This protein was further purified by DEAE-cellulose-52 chromatography and Sephadex G-200 size-exclusion chromatography to obtain three fractions, named AMWPDG2, AMWPDG4 and AMWPDG6. Then, their immunomodulatory activities were evaluated by using cell model experiments. The results indicated that the protein fractions could significantly increase the proliferation of splenic lymphocytes, peritoneal macrophages and bone-marrow-derived cells (BMDCs). AMWPDG2 showed the highest immunocompetence. AMWPDG2, AMWPDG4 and AMWPDG6 not only significantly improved the phagocytosis and immunomodulatory factors (interleukin (IL)-6, tumor necrosis factor-α, nitric oxide, hydrogen peroxide) secretion of peritoneal macrophages, but also promoted the expression of inflammatory cytokines (IL-6, IL-12 p40, IL-1β, IL-1α) and chemokines (CXCL1, CCL3) in BMDCs.

CONCLUSION

Taken together, these results indicated that three protein fractions from the A. membranaceus waste might be a potential natural immunomodulator. Moreover, it also provided the theoretical basis for further researching the mechanism of AMWPDG2, AMWPDG4 and AMWPDG6 on improving the immune response. © 2019 Society of Chemical Industry.

Extract Methods, Molecular Characteristics, and Bioactivities of Polysaccharide from Alfalfa (Medicago sativa L.)

The polysaccharide isolated from alfalfa was considered to be a kind of macromolecule with some biological activities; however, its molecular structure and effects on immune cells are still unclear. The objectives of this study were to explore the extraction and purifying methods of alfalfa (Medicago sativa L.) polysaccharide (APS) and decipher its composition and molecular characteristics, as well as its activation to lymphocytes. The crude polysaccharides isolated from alfalfa by water extraction and alcohol precipitation methods were purified by semipermeable membrane dialysis. Five batches of alfalfa samples were obtained from five farms (one composite sample per farm) and three replicates were conducted for each sample in determination. The results from ion chromatography (IC) analysis showed that the APS was composed of fucose, arabinose, galactose, glucose, xylose, mannose, galactose, galacturonic acid (GalA), and glucuronic acid (GlcA) with a molar ratio of 2.6:8.0:4.7:21.3:3.2:1.0:74.2:14.9. The weight-average molecular weight (Mw), number-average molecular weight (Mn), and Z-average molecular weight (Mz) of APS were calculated to be 3.30 × 10⁶, 4.06 × 10⁵, and 1.43 × 10⁸ g/mol, respectively, according to the analysis by gel permeation chromatography-refractive index-multiangle laser light scattering (GPC-RI-MALS). The findings of electron ionization mass spectrometry (EI-MS) suggest that APS consists of seven linkage residues, namely 1,5-Araf, galactose (T-D-Glc), glucose (T-D-Gal), 1,4-Gal-Ac, 1,4-Glc, 1,6-Gal, and 1,3,4-GalA, with molar proportions of 10.30%, 4.02%, 10.28%, 52.29%, 17.02%, 3.52%, and 2.57%, respectively. Additionally, APS markedly increased B-cell proliferation and IgM secretion in a dose- and time-dependent manner but not the proliferation and cytokine (IL-2, -4, and IFN-γ) expression of T cells. Taken together, the present results suggest that APS are macromolecular polymers with a molar mass (indicated by Mw) of 3.3 × 10⁶ g/mol and may be a potential candidate as an immunopotentiating pharmaceutical agent or functional food.

The Effects of Partially or Completely Substituted Dietary Zinc Sulfate by Lower Levels of Zinc Methionine on Growth Performance, Apparent Total Tract Digestibility, Immune Function, and Visceral Indices in Weaned Piglets

Simple Summary

This study was conducted to assess the effects of five diets with different doses and sources of zinc (Zn) on the growth performance (average daily gain, average daily food intake and gain to feed ratio), apparent total tract digestibility of nutrients, serum metabolites and immune functions of weaned piglets. The control diet contained 100 mg/kg inorganic Zn from ZnSO₄. The total dose of Zn in experimental diets was lower than that of the control diet, and the inorganic Zn from ZnSO₄ was gradually replaced by organic Zn from ZnMet. Therefore, the experimental diets were a basal diet containing 75 + 12.5, 50 + 25, 25 + 37.5, and 0 + 50 mg/kg Zn from ZnSO₄ and ZnMet, respectively. No differences were observed in growth performance, nutrient digestibility and serum metabolites. However, Zinc digestibility and parameters relating to body immune functions were improved when at least 50 mg of inorganic Zn was replaced by organic Zn. Thus supplementing 50 mg of inorganic Zn from ZnSO₄ plus 25 mg of organic Zn from ZnMet to piglets would be the best strategy to benefit the immune system and maintain growth performance under the conditions of the current study.

Abstract

The study aimed to evaluate the effects of replacing zinc sulfate (ZnSO₄) with a lower level of zinc methionine (ZnMet) on the growth performance, apparent total tract digestibility (ATTD) of nutrients, serum metabolites and immune functions of weaned piglets. Thirty-five weaned Duroc × Landrace × Large White male piglets (10.69 ± 0.26 kg) were randomly allotted to five diets. The control diet was supplemented with 100 mg/kg of Zn from ZnSO₄, and experimental diets included 75 + 12.5, 50 + 25, 25 + 37.5, and 0 + 50 mg/kg of Zn from ZnSO₄ and ZnMet, respectively. The results showed that no differences were observed in growth performance, ATTD of nutrients and serum metabolites among treatments, while serum white blood cell count, lymphocyte count, IgM contents and spleen index were higher (p < 0.01) in piglets fed with 50 + 25 mg/kg of Zn. Zinc digestibility (p < 0.05), IgA content (p < 0.001) and thymus index (p < 0.05) were increased when at least 50% of ZnSO₄ was replaced by ZnMet. All the results indicated that using a lower level of ZnMet in weaned piglet’s diet instead of ZnSO₄ had no adverse impacts on ATTD of nutrients and serum metabolites; and a 50 + 25 mg/kg of Zn (from ZnSO₄ and ZnMet, respectively) diet showed the best advantages for parameters relating to immune functions.

Immunomodulatory, antioxidant and intestinal morphology-regulating activities of alfalfa polysaccharides in mice

The effects of alfalfa polysaccharides (APS) on immunomodulatory and antioxidant functions, as well as intestinal morphology were investigated in vivo in this study. Sixty-four mice were randomly divided into four groups and administered 0, 200, 400 or 800 mg/kg/d body weight APS via gavage for 28 days. The blood parameters and metabolites, viscera indices, antioxidant enzyme activities and intestinal morphology were measured. The results showed that the oral administration of APS improved the immune functions of mice, significantly enhanced the white blood cells and lymphocyte counts, and led to improvements in spleen and thymus indices. APS exhibited significant antioxidant activity by enhancing total antioxidant capacity, superoxide dismutase and glutathione peroxidase activities in heart, kidney and liver, and decreasing the malondialdehyde levels of heart and liver. Moreover, administration of APS potently enhanced the small intestinal villous height and the villus-to-crypt ratio, and decreased the crypt depth of duodenum in mice. Therefore, we can conclude that APS possesses pronounced immunomodulatory activities, and plays an important role in the prevention of oxidative stresses and in the improvement of intestinal morphology in the immunological system in vivo. APS thus shows potential for the development as an effective natural immunomodulatory and antioxidant agent.

Immune-enhancing effects of anionic macromolecules extracted from Codium fragile on cyclophosphamide-treated mice

Immune-regulation and homeostasis are critical in cancer therapy and immunomodulatory biomaterials have been used to decrease side effects of immunosuppressant drugs. Anionic macromolecules (CFAMs) were isolated from the seaweed Codium fragile, and its immune-enhancing biological activities were examined in CY-induced immunosuppressed mice. CFAMs improved the splenic lymphocyte proliferation, NK cell activity, and spleen index. The expression of immune-associated genes was highly upregulated in splenic lymphocytes, and gene expression was differently regulated according to mitogens such as T-cell (Con A) and B-cell (LPS) mitogens. Additionally, CFAMs boosted the proliferation, NO production, and phagocytosis of peritoneal macrophages. CFAMs also considerably stimulated immune-associated gene expression in peritoneal macrophages. Moreover, our results showed CFAMs mediated its immune-enhancing effects via the MAPK pathway. These suggested CFAMs can be used as a potent immunomodulatory material under immune-suppressive condition. Furthermore, CFAMs may also be used as a bio-functional and pharmaceutical material for improving human health and immunity.

Se-enriched G. frondosa polysaccharide protects against immunosuppression in cyclophosphamide-induced mice via MAPKs signal transduction pathway

To assess the immunomodulatory and antioxidant activities of a Se-polysaccharide from Se-enriched G. frondosa (Se-GFP-22), immunosuppressed mice models were generated by cyclophosphamide (CTX) administration and then treated with Se-GFP-22. Results showed that Se-GFP-22 could increase thymus and spleen indices, phagocytic index, co-mitogenic (ConA- or LPS-stimulated) activities on splenocytes, DTH reaction, serum hemolysin formation and immunoglobulin (Ig G, Ig A and Ig M) levels in CTX-treated mice. Se-GFP-22 significantly enhanced the antioxidant activity in CTX-treated mice, as shown by the evaluation of GSH-Px, SOD and CAT activities, as well as MDA levels in serum, liver and kidney. Se-GFP-22 strongly stimulated inflammatory cytokines (IL-2 and IFN-γ) and NO productions by up-regulating mRNA expressions of IL-2, IFN-γ and iNOS. Se-GFP-22 possessed the immunomodulatory activity by up-regulating various transcription factors (JNK, ERK, and p38) in MAPKs signaling pathways. This study suggested that Se-GFP-22 may provide an alternative strategy in lessening chemotherapy-induced immunosuppression.

Sargassum Fusiforme Polysaccharide SFP-F2 Activates the NF-κB Signaling Pathway via CD14/IKK and P38 Axes in RAW264.7 Cells

Sargassum fusifrome is considered a "longevity vegetable" in Asia. Sargassum fusifrome polysaccharides exhibit numerous biological activities, specially, the modulation of immune response via the NF-κB signaling pathway. However, the precise mechanisms by which these polysaccharides modulate the immune response through the NF-κB signaling pathway have not been elucidated. In this study, we purified and characterized a novel fraction of Sargassum fusifrome polysaccharide and named it SFP-F2. SFP-F2 significantly upregulated the production of the cytokines TNF-α, IL-1β and IL-6 in RAW264.7 cells. It also activated the NF-κB signaling pathway. Data obtained from experiments carried out with specific inhibitors (PDTC, BAY 11-7082, IKK16 and SB203580) suggested that SFP-F2 activated the NF-κB signaling pathway via CD14/IKK and P38 axes. SFP-F2 could therefore potentially exert an immune-enhancement effect through inducing the CD14/IKK/NF-κB and P38/NF-κB signaling pathways.

The Polysaccharides from Codonopsis pilosula Modulates the Immunity and Intestinal Microbiota of Cyclophosphamide-Treated Immunosuppressed Mice

Based on previous studies about microflora regulation and immunity enhancement activities of polysaccharides from Codonopsis pilosula Nannf. var. modesta (Nannf.) L. T. Shen (CPP), there is little study on intestinal mucosal immunity, which is a possible medium for contacting microflora and immunity. In the present study, the BALB/c mice were divided into five groups (eight mice in each group), including a normal group (Con), a model control group (Model), and model groups that were administered CPP (50, 100, 200 mg/kg/d) orally each day for seven days after intraperitoneal injection of 60 mg/kg BW/d cyclophosphamide (CP) for three days. CPP recovered the spleen index and restored the levels of IFN-γ, IL-2, IL-10, as well as serum IgG. In addition, it elevated ileum secretory immunoglobulin A (sIgA), the number of Lactobacillus and acetic acid content in cecum. These results indicated that CPP plays an important role in the protection against immunosuppression, especially mucosa immune damage, and the inhibition of pathogenic bacteria colonization, which could be considered a potential natural source of immunoregulator.

Oligopeptide derived from solid-state fermented cottonseed meal significantly affect the immunomodulatory in BALB/c mice treated with cyclophosphamide

In this study, the immunomodulatory activity of oligopeptide (CP) derived from solid-state fermented cottonseed meal were investigated in immunosuppressed BALB/c mice models by treatment with cyclophosphamide (CY). Results indicated that oligopeptide increased the thymus and spleen indices of CY-treated mice. The count of plague forming cells (PFC) and the content of half serum hemolysis (HC₅₀) in immunosuppressive mice were restored to the normal level in CP-10 and CP-20 groups while the cytokines interleukin (IL)-2, IL-6, and tumor necrosis factor alpha (TNF-α) were increased significantly in CP-20 group. Similar increasing the immunoglobulin of IgG and IgM content in the serum of CP-10 group were also observed. These findings indicated that oligopeptide derived from solid-state fermented cottonseed meal had a strong immune-enhancing activity as well as a protective effect against immunosuppression induced by cyclophosphamide in mice.

Alveolar Bone Protective Effect of Hiziki Extracts on the Progression of Periodontitis

The purpose of this study was to evaluate the effects of hiziki extract on alveolar bone loss, inflammation, and osteo-biomarker expression in hPDL cells (10, 50, 100 μg/ml final concentrations in culture medium) and on a ligature-induced periodontitis rat model (50, 100, 200 mg/kg with oral administration). Hiziki extract increased alkaline phosphatase activity and mineralized nodule formation in hPDL cell. In western blot analysis, hiziki extract resulted in increased expression of osteoblast markers, including transforming growth factor beta (TGF-β), SMAD anchor for receptor activation (SARA) and runt-related transcription factor 2 (RUNX2) in hDPL cells. Additionally, expression of osteoclast markers and inflammatory cytokines was inhibited, which were receptor activator of NF-κB (RANK), RANK receptor (RANKL) and nuclear factor of activated T cells, cytoplasmic 1 (NFATc1). Hiziki extract also prevented alveolar bone loss in a ligature-induced periodontitis rat model through reducing the distance between cementoenamel junction and alveolar bone crest (CBJ-ABC) and furcation involvement. These findings suggested that hiziki extract has prophylactic potential for the prevention of periodontitis through anti-inflammation and, anti-bone resorption effects and the inhibition of alveolar bone destruction.

Antitumor activity and underlying mechanism of Sargassum fusiforme polysaccharides in CNE-bearing mice

This study was designed to investigate the antitumor effects of Sargassum fusiforme polysaccharides (SFPS) on nasopharyngeal carcinoma (NPC) and the underlying mechanism of its effect on splenic lymphocytes. As a result, SFPS significantly inhibited the growth of nasopharyngeal carcinoma CNE in vivo, and remarkably increased the serum cytokines and IgM levels in CNE-bearing mice. Meanwhile, SFPS stimulated the peritoneal macrophages to secrete the cytokines, exerted a stimulatory effect on splenic lymphocytes proliferation, and increased the expression of IgM from splenic lymphocytes. The pretreatment of splenic lymphocytes with special antibodies (anti-TLR4 and anti-TLR2) significantly suppressed the proliferation of splenic lymphocytes and blocked SFPS-induced IgM production. SB203580, a specific inhibitor of p38 MAPK, effectively suppressed SFPS-induced IgM secretion in splenic lymphocytes. Taken together, SFPS has antitumor and immunomodulatory activities in NPC, and its activity is mediated, at least in part, by TLR2/TLR4 receptors and p38 MAPK signaling pathway.

Protective Effect of Chitosan Oligosaccharides Against Cyclophosphamide-Induced Immunosuppression and Irradiation Injury in Mice

Chitosan oligosaccharides (COS), hydrolyzed products of chitosan, was found to display various biological activities. Herein, we assessed the immunostimulatory activity of COS both in in vitro and in vivo studies. In vitro cytotoxicity studies to murine macrophage RAW264.7 revealed that COS is safe even at the maximum tested concentration of 1000 μg/mL. It also stimulates the production of nitric oxide (NO) and tumor necrosis factor (TNF-α) and enhances the phagocytosis in COS-stimulated RAW264.7. We have shown that the COS could significantly (P < 0.05) restore the reduced immune organs indices, phagocytic index, lymphocyte proliferation, natural killer cell activity, and antioxidant enzyme activities in a cyclophosphamide-induced immunosuppressed mice model. COS can also improve the survival rate in irradiation injury mice and significantly (P < 0.05) increased the spleen indices and up-regulates the CD4+/CD8+ ratio in splenocytes. In sum, the aforementioned results suggest that COS might has the potential to be used as an immunostimulatory agent in patients with immune dysfunctions or be a model for functional food development.

PRACTICAL APPLICATION

COS might has the potential to be used as an immunostimulatory agent in patients with immune dysfunctions or be a model for functional food development.

Preliminary characterization of the structure and immunostimulatory and anti-aging properties of the polysaccharide fraction ofHaematococcus pluvialis

In this study, a polysaccharide fraction (HPP-c3-s1) was obtained from Haematococcus pluvialis using DEAE-52 anion exchange and Sephacryl S400 chromatographies. The structure of HPP-c3-s1 was partially characterized and its biological activity was investigated. HPP-c3-s1 is a homogeneous polysaccharide with a molecular weight of 23 413 kDa as determined by high-performance gel permeation chromatography and polyacrylamide gel electrophoresis. Periodate oxidation and Smith degradation analysis combined with GC-MS determined that HPP-c3-s1 contains 1 → 2, 1 → 3, 1 → 4, and probably a few 1 → 6 glycosyl linkages. Fourier transform infrared spectroscopy and nuclear magnetic resonance analyses indicate HPP-c3-s1 is a pyranose containing an amino and O-acetyl group. The sugar chains in HPP-c3-s1 contain both α and β glycosidic configurations, where the β configuration is the primary form. It was observed that the HPP-c3-s1 nanostructure had linear and branched forms at a concentration of 5 μg mL⁻¹ and created different sized aggregates at a higher concentration of 50 μg mL⁻¹. Furthermore, HPP-c3-s1 had significant immunostimulatory effects on splenocytes and B lymphocytes. In assays assessing anti-aging effects, HPP-c3-s1 extended the mean survival of Caenorhabditis elegans without adversely affecting reproduction. In addition, treatment with HPP-c3-s1 resulted in delays in age-related physiologic parameters, including body movement, rates of head swing and body bending, and accumulation of intestinal lipofuscinosis in C. elegans. Overall, these results suggest HPP-c3-s1 has remarkable immunomodulatory and anti-aging properties that may serve as the basis for development of functional foods and dietary supplements.

HPP-c3-s1 is a pyranose with an average molecular weights of 23 413 kDa, which exhibited siginificant immunomodulatory and anti-aging activities.

Mixing ratio optimization for functional complex extracts of Rhodiola crenulata, Panax quinquefolius, and Astragalus membranaceus using mixture design and verification of immune functional efficacy in animal models

We aimed to identify the optimum mixing ratio for various ingredients to obtain complex extracts with high extract yields and immune-enhancing activity in animals. The extract yield and amounts of nitric oxide (NO) and interleukin (IL)-6 were set to maximum for modeling predictions. The predicted optimum values for the mixing ratio were 49.5% for Rhodiola crenulata, 26.1% for Astragalus membranaceus, and 24.4% for Panax quinquefolius, and the predicted response values were 31.5% yield, 13.4% NO production, and 6.1% IL-6 production; actual values were 35.3% yield, 14.7% NO, and 6.6% IL-6. The optimum mixing ratio extract (OMRE) was used for the animal experiments. Treating mice with OMRE at 200 mg/kg produced significant increases in spleen indexes and T-cell/B-cell proliferation. OMRE treatment increased IL-10 and IL-6 production in concanavalin A- and lipopolysaccharide-induced T- and B- lymphocytes, respectively. These results provide a basis for the development of functional extracts and drinks.

Immuno-enhancement effect of polysaccharide extracted from Stichopus japonicus on cyclophosphamide-induced immunosuppression mice

Polysaccharide (SJP) was extracted from Sea cucumber, Stichopus japonicas, and its immune-enhancing activities were evaluated in vivo immune-suppressed mice systems. Cyclophosphamide(CY)-treated mice were orally administrated with SJP according to different concentrations. The results showed that administration of SJP significantly increased spleen index without variation of the body weight, compared to only CY treatment group. The proliferation of splenic lymphocyte and NK activity was also stimulated by SJP. In addition, the oral administration of SJP up-regulated COX-2 and TLR-4 as well as cytokines such as IL-1β, IL-4, IL-6, IL-10, TNF-α and IFN-γ, which are secreted from splenic lymphocytes in cyclophosphamide-treated mice. Moreover, our results showed that SJP stimulated macrophages via NF-κB and MAPK signaling pathways. These findings provided the potential use of SJP as an alternative means under immune-suppressed conditions, and furthermore can be utilized as a functional material for food and pharmaceutical industries.

Immunoenhancement of Edible Fungal Polysaccharides (Lentinan, Tremellan, and Pachymaran) on Cyclophosphamide-Induced Immunosuppression in Mouse Model

Fungal polysaccharides display a variety of important biological activities, including anti-inflammatory, antitumor, and immune-stimulating activities. The aim of present study was to investigate the immunomodulatory effect of fungal polysaccharides on cyclophosphamide-induced immunosuppression in mice. Mice were pretreated orally with lentinan, tremellan, pachymaran, or a mixture of the three, respectively. The results showed that pretreatments with polysaccharides significantly increased the thymus index in cyclophosphamide-induced immunosuppression mice. The level of the cytokine IL-10 in sera of cyclophosphamide-induced mice was decreased after pretreatments of polysaccharides. Flow cytometry results showed that pretreatments with polysaccharides enhanced the phagocytosis of peritoneal macrophages in mice. The increased levels of serum antibody IgG and IgM were observed in the groups pretreated with polysaccharides. Our work demonstrated that the treatment of polysaccharides elicited strong immune activity and a protective effect against cyclophosphamide-induced immunosuppression.

Immunoenhancement Effects of Glycosaminoglycan from Apostichopus japonicus: In Vitro and In Cyclophosphamide-Induced Immunosuppressed Mice Studies

In this study, the immunomodulatory activities of Apostichopus japonicus glycosaminoglycan (AHG) on the nature killer (NK) cells, cytotoxic T lymphocytes (CTLs) and cyclophosphamide (CY)-treated mice were investigated. After stimulation with multiple concentrations of AHG (0–100 μg/mL), NK cells and CTLs displayed outperformance against YAC-1 and B16 cells, respectively. Furthermore, the mitogen-induced splenic lymphocyte proliferation in CY-induced immunosuppressed mice was significantly promoted by AHG. In addition, the administration of AHG dramatically increased the splenocytes Ca²⁺ concentration and the delayed-type hypersensitivity (DTH) reaction in a dose-dependent manner. Besides, AHG could strongly increase the total antioxidant capacity (T-AOC), the activities of superoxidase dismutase (SOD), catalase (CAT) as well as glutathione peroxidase (GSH-PX), and could decrease the malondialdehyde (MDA) level in the heart, kidney and liver. These findings indicated that AHG played an important role in the immune enhancement and protection against CY-induced immunosuppression and oxidative damage. Our findings provide experimental evidence for further research and possible immunostimulatory applications of AHG in clinical practice.

Fucoidan and Fucosylated Chondroitin Sulfate Stimulate Hematopoiesis in Cyclophosphamide-Induced Mice

Application of cytostatics in cancer patients’ chemotherapy results in a number of side effects, including the inhibition of various parts of hematopoiesis. Two sulfated polysaccharides, fucoidan from the seaweed Chordaria flagelliformis (PS-Fuc) and fucosylated chondroitin sulfate from the sea cucumber Massinium magnum (PS-FCS), were studied as stimulators of hematopoiesis after cyclophosphamide immunosuppression in mice. Recombinant granulocyte colony-stimulating factor (r G-CSF) was applied as a reference. Both tested polysaccharides PS-Fuc and PS-FCS have a similar activity to r G-CSF, causing pronounced neutropoiesis stimulation in animals with myelosuppression induced by cyclophosphamide (CPh). Moreover, these compounds are also capable to enhance thrombopoiesis and erythropoiesis. It should be noted that PS-FCS demonstrated a greater activity than r G-CSF. The results indicate the perspective of further studies of PS-Fuc and PS-FCS, since these compounds can be considered as potentially promising stimulators of hematopoiesis. Such drugs are in demand for the accompanying treatment of cancer patients who suffer from hematological toxicity during chemo and/or radiation therapy.

The development and use of a drug-induced immunosuppressed rat-model to screen Phela for mechanism of immune stimulation

ETHNOPHARMACOLOGY RELEVANCY

Phela, is code name for a medicinal product made from four South African traditional medicinal plants (Clerodendrum glabrum E. Mey, Polianthes tuberosa (Linn.), Rotheca myricoides (Hochst.) Steane & Mabb. and Senna occidentalis (L.) Link). All these plants have established traditional use in a wide spectrum of diseases. Phela is under development for use as an immune booster in immunocompromised patients, which includes patients with the human immunodeficiency virus (HIV). Already several studies, both pre-clinical and clinical, have shown that Phela is a safe and effective immune booster. Despite some studies on the action of Phela, the mechanism of action by Phela is still not known. Understanding the mechanism of action will enable safer and effective use of the drug for the right indications. Unfortunately, there is no well characterized test-system for screening products for immune stimulant activity. Therefore, the objective of this study was to use Phela as the test article, to develop and validate a rat-model (test system) by which to screen medicines for immune stimulant activity.

MATERIAL AND METHODS

First, the batch of Phela used was authenticated by high performance liquid chromatography (HPLC) techniques; analytical methods for the immunosuppressant drugs, cyclosporine A (CsA), cyclophosphamide (CP) and dexamethasone (Dex) were developed and validated; and a slide-A-Lyzer dialysis was used to test for potential interactions in rat plasma of Phela with CsA, CP and Dex. Thereafter, using Sprague Dawley (SD) rats and in separate experiments, the effective dose of Phela in the study animals was determined in a dose ranging study with levamisole, a known immune stimulant as the positive control; the appropriate doses for immunosuppression by CsA, CP and Dex were determined; the time to reach 'established immunosuppression' with each drug was determined (it was also the time for intervention with Phela); and eventually, the effect of Phela on the immune system was tested separately for each drug induced immunosuppression. The immune system was monitored by observing for changes in plasma profiles of IL-2, IL-10, IgG, IgM, CD4 and CD8 cell counts at appropriate intervals, while in addition to function tests, the kidneys, liver, spleen, thymus, were weighed and examined for any pathology.

RESULTS

The chromatographic fingerprint certified this batch of Phela as similar to the authentic Phela. There was no significant interaction between Phela and CsA, CP and Dex. The effective dose of Phela was determined to be 15.4mg/kg/day. Phela led to a moderate increase in the immune parameters in the normal rats. Co-administration of Phela 15mg/kg/day orally for 21 days with CsA led to stoppage and reversal of the immunosppressive effects of CsA that were exhibited as increased IL-2, IL-10, CD4 and CD8 counts, implying that Phela stimulates the cell mediate immunity (CMI). For CP, Phela led to stoppage and reversal, though moderate, of CP-induced suppression of IL-10, IgM and IgG only, implying that Phela stimulates the humoral immunity (HI) too. Phela had no effect on Dex induced immunosuppression. Stimulation of the CMI means that Phela clinical testing programme should focus on diseases or disorders that compromise the CMI, e.g., HIV and TB. The stimulation of the HI immunity means that Phela may stimulate existing memory cells to produce antibodies.

CONCLUSION

The present study has revealed Phela's mechanism of action as mainly by stimulation of the CMI, implying that the use of Phela as immune booster in HIV patients is appropriate; and that using Phela as the test product, a rat model for screening medicinal products for immune stimulation has been successfully developed and validated, with a hope that it will lead to the testing of other related medicinal products.

Antitumor effects of polysaccharide from Sargassum fusiforme against human hepatocellular carcinoma HepG2 cells

Sargassum fusiforme (Harv.) Setchel, a kind of brown algae, has been applied as a therapeutic for thousands of years. This study was designed to investigate the antitumor effects of the polysaccharide (SFPS) from S. fusiform in liver cancer. The mice inoculated with HepG2 cells were orally administrated with SFPS at the doses of 100, 200 and 400 mg/kg body weight for 28 days. The products from peritoneal macrophages and serum in HepG2-bearing mice were measured. The effect of SFPS-induced cell apoptosis was measured by flow cytometry. Meanwhile, the expression levels of Bax and Bcl-2 were detected. Furthermore, the cytotoxicity of SFPS was evaluated by CCK-8 assay. Results showed that SFPS significantly inhibited growth of human HepG2 cell-transplanted tumor in nude mice, and remarkably increased serum TNF-α, IL-1, NO and IgM levels in HepG2-bearing mice. SFPS also promoted the cytokines (IL-1 and TNF-α) secreted by peritoneal macrophages in HepG2-bearing mice. SFPS exerted a stimulatory effect on apoptosis of HepG2 cells, increased the expression of Bax, and decreased the expression of Bcl-2. The results indicated that SFPS has anti-tumor and immunomodulatory activities at the high concentration, and it could be used as a potential chemopreventative and/or adjuvant chemotherapeutic agent in liver cancer.

Optimization and evaluation of astragalus polysaccharide injectable thermoresponsive in-situ gels

The objective of this study was to develop an injectable in situ forming gel system based on Poloxamer for sustained release of Astragalus polysaccharide (APS), thus achieved once or twice administration instead of frequent dosing during long-term treatment. The optimal formulation is 10 g APS, 18 g poloxamer 407, 2 g poloxamer 188, 0.15 g CMC-Na, 0.85 g sodium chloride in 100 ml gel in situ which had a preferable sol-gel transition temperature(T sol-gel) (34.1 ± 0.4°C), and good stability. In vitro release studies, all formulations containing polymer additives had prolonged release time and decreased initial burst to some extent. The optimal formulation containing 0.15% CMC-Na showed a best sustained release profile for about 132 h with the lowest initial burst in vitro about 16.30% in 12 h). In vivo, Male BALB/c mice (18–20 g) were administrated with APS in-situ gel just once, the values of immune organ indices, spleen lymphocyte proliferation, and serum IgM, IgG, IL-2 and IL-6 had significant increase, which was consistent with the mice given daily APS injections (7 times), while the above indices were increased more significantly in which administrated with APS in-situ gel twice. Based on these results, it can be concluded that the Poloxamer depot is a promising carrier for the sustained release of APS with an ideal release behavior.

Sargassum fusiforme polysaccharides inhibit VEGF-A-related angiogenesis and proliferation of lung cancer in vitro and in vivo

Sargassum fusiforme (Harv.) is a brown alga belonging to the Sargasaceae family. The Sargassum fusiforme polysaccharides (SFPS) have demonstrated good anti-tumor and immunomodulatory activity. However, the underlying mechanisms of its anti-tumorigenesis, especially the anti-angiogenic activity is yet to be established. In the present study, we attempted to determine the effects of SFPS on the human lung adenocarcinoma SPC-A-1 cells and its xenograft model. The results showed that SFPS provides a concentration-dependent inhibition of SPC-A-1 cell proliferation in in vitro and the tumor growth in in vivo studies. Immunohistochemistry studies revealed that the administration of SFPS significantly decreased CD31, VEGF-A expression and the tumor microvessel density (MVD). SFPS also provided a dose-dependent impairment of cell vitality, induction of cell cycle arrest and apoptosis of human umbilical vein endothelial cells (HUVECs). SFPS inhibited the expression of VEGF-A in tumor cells and its receptor VEGFR2 in HUVECs. The HUVEC tube formation assay showed that SFPS could abrogate the tube formation with relatively decreased tubes length of tube-like capillary similar to anti-VEGF antibody, Avastin®. These findings suggested that SFPS could be used as an alternative anticancer drug as they inhibited the angiogenesis and the microvessel formation through disruption of VEGF signals apart from direct tumor cytotoxicity.

A polysaccharide from Sargassum thunbergii inhibits angiogenesis via downregulating MMP-2 activity and VEGF/HIF-1α signaling

A water-soluble polysaccharide (STPC2) was isolated from the boiling-water extract of Sargassum thunbergii, purified by CaCl2 precipitation and chromatography on DEAE-cellulose and Sephacryl S-300 column. It was found that STPC2, with a molecular weight of 57kD, was composed of fucose, xylose, galactose and glucuronic acid, in a ratio of 8.1: 3.8: 2.1: 1.0. Additionally, we found that STPC2 significantly inhibited endothelial cell migration and tube formation without toxicity. Moreover, STPC2 significantly inhibited lung cancer cell A549 migration and proliferation. It was found that STPC2 treatment suppressed MMP-2 gene expression at transcriptional level and enzymatic activity. Furthermore, STPC2 reduced the mRNA and protein expression of vascular endothelial growth factor-A (VEGF-A) and hypoxia-inducible factor (HIF)-1 alpha in the endothelial cells. Taken together, our findings indicated that STPC2 was a potent bioactive polysaccharide with distinct anti-angiogenesis activity against tumor migration via down-regulation of MMP-2 activity and VEGF/HIF-1α signaling pathway.

Standardized extract of Tinospora crispa stimulates innate and adaptive immune responses in Balb/c mice

Standardized extract of Tinospora crispa has been shown to exhibit immunostimulatory effects on innate immune responses in Wistar-Kyoto rats by enhancing neutrophil and T cell-mediated immunity. In this study the immunostimulatory effects of T. crispa were further investigated on the cellular immune response by determining its effect on nitric oxide (NO) production ability, peritoneal macrophage phagocytosis and delayed type hypersensitivity (DTH), whereas the humoral immune response was evaluated through the measurement of serum immunoglobulins (IgG and IgM) and serum lysozyme levels. Male Balb/c mice were immunized with 200 μL of 5 × 10(9) sheep red blood cells (sRBCs) per mL on day 0 and orally administered with 50, 100 and 200 mg per kg of ethanol extract of T. crispa for 14 days. Syringin and magnoflorine were qualitatively and quantitatively analyzed in the extract as chemical markers by using a validated reversed-phase high performance liquid chromatography method. T. crispa extract (TCE) considerably improved the peritoneal macrophages' ability to engulf FITC-labeled E. coli in a dose-dependent manner. TCE also dose-dependently promoted NO production in peritoneal macrophages activated by a lipopolysaccharide (LPS) and markedly potentiated the sRBS-induced swelling rate of the mice paw in DTH. The extract significantly enhanced the level of serum immunoglobulins, showing maximum activity at 100 mg kg(-1). Compared to the control groups, the serum lysozyme level and myeloperoxidase (MPO) activity were significantly higher in extract-treated groups. These findings suggest that T. crispa possesses strong immunostimulatory activities and might act as a natural immunomodulator as well as a potential nutraceutical for the modulation of the immune response.

Improved antioxidant and anti-tyrosinase activity of polysaccharide from Sargassum fusiforme by degradation

An efficient method for the degradation of polysaccharides isolated from Sargassum fusiforme (PSF) was developed by using ascorbic acid in combination with H2O2. The degradation conditions were optimized using a Box-Behnken response surface design (BBRS). The optimum conditions were established as: concentration of ascorbic acid (VC) and H2O2 17.26mM, degradation temperature 51°C and degradation time 1.6h. The DPPH radical scavenging rate of the degraded polysaccharides from S. fusiforme (DPSF) obtained under the optimal conditions was determined to be 75.22±0.02%, which was well matched with the value (75.21%) predicted by the BBRS model. In vitro antioxidant activity of the polysaccharides was evaluated by determining their radical (hydroxyl radical, superoxide anion radical and DPPH radical) scavenging abilities, and ferric iron reducing power. The inhibitory activity on tyrosinase of DPSF was also evaluated. The results indicate that the degraded polysaccharide has superior antioxidant activity and anti-tyrosinase effect to those of the original polysaccharide.

Immune-Enhancing Effects of a High Molecular Weight Fraction of Cynanchum wilfordii Hemsley in Macrophages and Immunosuppressed Mice

The objective of this study was to investigate the immune-enhancing activity of a high molecular weight fraction (HMF) of Cynanchum wilfordii in RAW 264.7 macrophages and the cyclophosphamide (CYC)-induced mouse model of immunosuppression. To identify the bioactive substances of HMF, a crude polysaccharide (HMFO) was obtained and treated with sodium periodate (an oxidation agent) or digested with protease. In macrophages, HMF treatment enhanced the production of nitric oxide (NO) and cytokines (tumor necrosis factor alpha (TNF-α), interleukin 6 (IL-6), and interleukin 1β (IL-1β)), as well as phagocytic ability. In CYC-immunosuppressed mice, HMF improved relative spleen and thymus weights, natural killer (NK) cell activity, and splenic lymphocyte proliferation. These increases in NO and cytokines were mediated by up-regulation of nuclear factor kappa B (NF-κB) and mitogen-activated protein kinase (MAPK) signaling pathways. Periodate treatment, but not protease treatment, decreased the immune-enhancing activity of HMFO, suggesting that polysaccharides are the active ingredients in C. wilfordii extract.

Structural characterization and effect on anti-angiogenic activity of a fucoidan from Sargassum fusiforme

A fucoidan FP08S2 was isolated from the boiling-water extract of Sargassum fusiforme, purified by CaCl2 precipitation and chromatography on DEAE-cellulose and Sephacryl S-300. FP08S2 contained fucose, xylose, galactose, mannose, glucuronic acid, and 20.8% sulfate. The sulfate groups were attached to diverse positions of fucose, xylose, mannose, and galactose residues. The backbone of FP08S2 consisted of alternate 1,2-linked α-D-Manp and 1,4-linked β-D-GlcpA. Sugar composition analysis and ESI-MS revealed that the oligosaccharides from branches contained fucose, xylose, galactose, glucuronic acid and sulfate. FP08S2 could significantly inhibit tube formation and migration of human microvascular endothelial cells (HMEC-1) dose-dependently. These results suggested that the fucoidan FP08S2 from brown seaweeds S. fusiforme could be a potent anti-angiogenic agent.

Structural characterization and biological activities of two α-glucans from radix paeoniae alba

Radix Paeoniae Alba is widely used in Chinese traditional medicine to treat various diseases such as gastrointestinal disorders, cancer, and other diseases. In this study, two polysaccharides RPAPW1 and RPAPW2 were isolated from Radix Paeoniae Alba by DEAE-52 cellulose chromatography and G-25 sephadex. According to physicochemical methods, NMR and methylation analysis, RPAPW1 and RPAPW2 were established to be α-glucans consisting of predominant 4-linked α- Glc residues branched at O-6 and contained trace amount of protein and uronic acid. Immunological tests indicated that RPAPW1, RPAPW2 and could promote splenocyte proliferation and RAW264.7 phagocytic activity. In vitro, RPAPW1 and RPAPW2 elicited a week reducing power, DPPH scavenging activity and could not protect the PC12 cells from H2O2 damage. These data implied polysaccharides RPAPW1 and RPAPW2 had the potential to be a natural immunopotentiating and antioxidant supplement for preparing functional foods and nutraceuticals.