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

The efficient capture of polysaccharides in Tetradesmus obliquus of indole-3-acetic acid coupling sludge extraction

Polysaccharide is an important biomass of algae. The sludge extract is rich in organic substances, which can be used by algae for biomass growth and high-value biomass synthesis, but its organic toxicity has an inhibitory effect on algae. To overcome inhibition and improve polysaccharide enrichment, Tetradesmus obliquus was cultured with sludge extract with different indole-3-acetic acid (IAA) concentrations. Within 30 days of the culture cycle, T. obliquus showed in good condition at the IAA dosage content of 10-6 M, the maximum cell density and dry weight were respectively (106.78 ± 2.20) × 106 cell/mL and 2.941 ± 0.067 g/L while the contents of chlorophyll-a, chlorophyll-b, and carotenoid were 1.79, 1.91 and 2.80 times that of the blank group, respectively. The highest polysaccharide accumulation was obtained under this culture condition, reaching 533.15 ± 21.11 mg/L on the 30th day, which was 2.49 times that in the blank group. By FT-IR and NMR analysis, it was found that the polysaccharides of T. obliquus were sulfated polysaccharide with glucose and rhamnose as the main monosaccharides. Proteomic showed that the up-regulation of A0A383WL26 and A0A383WLM8 enhanced the light trapping ability, and A0A383WMJ2 enhanced the accumulation of NADPH. The up-regulation of A0A383WHD5 and A0A383WAY6 indicated that IAA culture could repair the damage caused by sludge toxicity, thus promoting the accumulation of biomass. The above findings provided new insights into the mechanism of sludge toxicity removal of T. obliquus and the enhancement of the polysaccharide accumulation effect under different concentrations of IAA.

Review of isolation, purification, structural characteristics and bioactivities of polysaccharides from Portulaca oleracea L

Portulaca oleracea L., also known as purslane, affiliates to the Portulacaceae family. It is an herbaceous succulent annual plant distributed worldwide. P. oleracea L. is renowned for its nutritional value and medicinal value, which has been utilized for thousands of years as Traditional Chinese Medicine (TCM). The extract derived from P. oleracea L. has shown efficacy in treating various diseases, including intestinal dysfunction and inflammation. Polysaccharides from P. oleracea L. (POP) are the primary constituents of the crude extract which have been found to have various biological activities, including antioxidant, antitumor, immune-stimulating, and intestinal protective effects. While many publications have highlighted on the structural identification and bioactivity evaluation of POP, the underlying structure-activity relationship of POP still remains unclear. In view of this, this review aims to focus on the extraction, purification, structural features and bioactivities of POP. In addition, the potential structure-activity relationship and the developmental perspective for future research of POP were also explored and discussed. The current review would provide a valuable research foundation and the up-to-date information for the future development and application of POP in the field of the functional foods and medicine.

Protective Effect of Artocarpus heterophyllus Lam. (Jackfruit) Polysaccharides on Liver Injury Induced by Cyclophosphamide in Mice

In recent years, Artocarpus heterophyllus Lam. (jackfruit) polysaccharides (namely JFP-Ps) have attracted much attention due to their multiple biological activities. This study aimed to explore the protective effects and the underlying mechanisms of JFP-Ps on cyclophosphamide (Cp)-induced liver damage. The protective effect of JFP-Ps was evaluated using HE staining, antioxidant testing, enzyme-linked immunosorbent assay (ELISA), real-time quantitative polymerase chain reaction (RT-qPCR), Western blot and ultra-performance liquid chromatography equipped with quadrupole time-of-flight mass spectrometry (UPLC-Q-TOF-MS/MS) metabolomics analysis. The results showed that Cp caused pathological liver damage, activated oxidative stress and downregulated cytokine expression, while JFP-Ps treatment was found to exert antioxidant effects and play immune regulatory roles through mitogen-activated protein kinase/nuclear factor-κB (MAPK/NF-κB) related inflammation and cell apoptosis pathways to protect the Cp-induced liver injury. Metabolomic results showed that the liver-protective effects of JFP-Ps were mainly related to aminoacyl transfer ribonucleic acid (tRNA) biosynthesis, sphingolipid metabolism, purine metabolism and the citrate cycle. These results indicate that JFP-Ps have great potential application in alleviating liver injury.

Dietary zinc-chitosan nanoparticles addition influences on growth performance, apparent total tract digestibility, carcass indices, and immune function in weaned rabbits

The aim of this study was to study the effect of zinc oxide-chitosan nanoparticles (Zn-CNPs) on growth performance, plasma constituents, carcass indices, and immune function in rabbit diets. Eighty weaned V-line males rabbits at 5 weeks of age were divided into four dietary groups of control diet; 50 Zn-CNPs; 75 Zn-CNPs;100 Zn-CNPs. Supplementation of Zn-CNPs did not affect final live body weight and average daily weight gain. 100 ppm Zn-CNPs recorded (p < 0.05) higher digestibility of DM, OM, CP, EE, and NFE. Dietary groups of 75 and 100 ppm were higher (p < 0.05) in DCP, TDN (%), and DE (kcal/kg). Zn-CNPs supplementation was higher (p < 0.05) in hot carcass and spleen weights %. The addition of Zn-CNPs in diets promoted dressing%. Significant increases (p < 0.05) in plasma total protein and albumin levels for 75 and 100 Zn-CNPs. Zn-CNPs decreased (p < 0.05) glucose, total cholesterol, LDL concentrations and increased (p < 0.05) plasma zinc levels, IgG, IgM. Plasma HDL level increased (p < 0.05) with 75 and 100 ppm Zn-CNPs. In conclusion, Zn-CNPs supplementations can use safely as a zinc source in rabbits diets without any detrimental effects on growth performance, plasma constituents, and carcass indices. Moreover, 50, 75, and 100 ppm Zn-CNPs enhanced the immune functions.

Arctoscopus japonicus Lipids Enhance Immunity of Mice with Cyclophosphamide-Induced Immunosuppression

A lipid extract was obtained from eggs of the sailfin sandfish, Arctoscopus japonicus. Immunostimulatory effects of A. japonicus lipids incorporated with PEG6000 (AJ-PEG) on immunosuppressed mice treated with cyclophosphamide (CY) were investigated. AJ-PEG was administered orally to mice at different concentrations of 25 to 100 mg/kg body weight (BW). CY was injected to mice intraperitoneally at 80 mg/kg BW. Administration of AJ-PEG significantly increased the spleen index of CY-treated mice. AJ-PEG also stimulated the proliferation of splenic lymphocytes and natural killer (NK) activity. Immune-associated cytokines such as IL-1β, IL-2, IL-4, IL-6, TNF-α, and IFN-γ as well as TLR4 were overexpressed in splenic lymphocytes. Furthermore, AJ-PEG significantly increased splenic CD4+ and CD8+ T lymphocytes. In peritoneal macrophages, AJ-PEG administration improved proliferation, nitric oxide (NO) production, and phagocytosis. It also upregulated iNOS, COX-2, IL-1β, IL-6, and TNF-α expression. Taken together, these results suggest that AJ-PEG can be used in animal models with immunosuppressive conditions as a potent immunomodulatory agent.

Immunomodulatory Effect of Flammulina rossica Fermentation Extract on Healthy and Immunosuppressed Mice

Flammulina rossica fermentation extract (FREP) was obtained by ethanol precipitation of the fermentation broth. The molecular weight of FREP is 28.52 kDa, and it mainly contains active ingredients such as polysaccharides, proteins, reducing sugars, and 16 amino acids. Among them, the polysaccharides were mannose, glucose, galactose, arabinose, and fucose and possessed β-glycosidic bonds. Furthermore, the immunoregulatory activities of FREP were investigated in vivo. The results demonstrated that FREP could increase the counts of CD4+ T lymphocytes and the ratio of CD4+/CD8+ in a dose-dependent manner in healthy mice. In addition, FREP significantly increased serum cytokines, including IL-2, IL-8, IL-10, IL-12, IL-6, IL-1β, INF-γ, C-rection protein, and TNF-α, and promoted splenocyte proliferation in healthy mice. Finally, FREP could restore the counts of white blood cells, red blood cells, secretory immunoglobulin A, and antibody-forming cells and significantly promote the serum haemolysin level in mice treated with cyclophosphamide. The findings indicated that FREP possessed immunoregulatory activity in healthy mice and could improve the immune functions in immunosuppressive mice. Therefore, FREP could be exploited as an immunomodulatory agent and potential immunotherapeutic medicine for patients with inadequate immune function.

Protective Effect of Anoectochilus formosanus Polysaccharide against Cyclophosphamide-Induced Immunosuppression in BALB/c Mice

In this study, Anoectochilus formosanus polysaccharide (AFP) was acquired a via water extraction and alcohol precipitation method. The immunoregulatory activity of AFP was first evaluated on cyclophosphamide (Cy)-treated mice. Galacturonic acid, glucose and galactose were confirmed to be the main components of AFP. AFP demonstrated the ability to stimulate the production of TNF-α and IL-6 in RAW 264.7 macrophages. Not surprisingly, the activation of the NF-κB signaling pathway by AFP was validated via Western blot analysis. Furthermore, AFP could alleviate Cy-induced immunosuppression, and significantly enhance the immunity of mice via increasing the thymus index and body weight, stimulating the production of cytokines (IgA, IgG, SIgA, IL-2, IL-6 and IFN-γ). The improvement in the intestinal morphology of immunosuppressed mice showed that AFP could alleviate Cy-induced immune toxicity. These results have raised the possibility that AFP may act as a natural immunomodulator. Overall, the study of AFP was innovative and of great significance for AFP's further application and utilization.

A sulfated polysaccharide from Dictyosphaeria cavernosa: Structural characterization and effect on immunosuppressive recovery

A homogeneous sulfated polysaccharide DCS1 was obtained from Dictyosphaeria cavernosa by alkali extraction and chromatography purification. On the basis of chemical and spectroscopic analyses, DCS1 was a novel mannan-type sulfated polysaccharide and had a molecular weight of 15.48 kDa. DCS1 consisted of a main chain of (1 → 4)-α-d-Manp units with partial sulfate substitution at C-2 and branches at C-2/C-6. DCS1 possessed a potent immune-enhancing effect in vitro evaluated by the assays of lymphocytes proliferation and macrophage phagocytosis. The immunomodulatory effect of DCS1 in vivo was further investigated using immunosuppressed mice induced by cyclophosphamide (Cy). The data showed that DCS1 markedly increased the spleen and thymus indexes, and ameliorated the Cy-induced damage to spleen and thymus. Moreover, DCS1 had a significant effect on hematopoietic function recovery, and promoted the secretion of the interleukin-2 and tumor necrosis factor-α. Notably, DCS1 reversed the reduction of CD4+ T cells, improved the disorder of CD4+/CD8+ T cells and enhanced the immune response. The investigation demonstrated that the sulfated polysaccharide DCS1 with novel structure could be a hopeful immunomodulatory agent.

Artemisia ordosica polysaccharide ameliorated LPS-induced growth inhibition and intestinal injury in broilers through enhancing immune-regulation and antioxidant capacity

The study investigated the effects of dietary Artemisia ordosica polysaccharide (AOP) on growth, intestinal morphology, immune responses and antioxidant capacity of broilers challenged with lipopolysaccharide (LPS). A total of 192 1-d-old broilers were randomly allotted to four treatments with 6 replicates (n = 8): (1) CON group, non-challenged broilers fed basal diet; (2) LPS group, LPS-challenged broilers fed basal diet; (3) AOP group, non-challenged broilers fed basal diet supplemented with 750 mg/kg AOP; (4) LPS+AOP group, LPS-challenged broilers fed basal diet supplemented with 750 mg/kg AOP. The trial included starter phase (d 1 to 14), stress period Ⅰ (d 15 to 21), convalescence Ⅰ (d 22 to 28), stress period Ⅱ (d 29 to 35) and convalescence Ⅱ (d 36 to 42). During stress period Ⅰ and Ⅱ, broilers were injected intra-abdominally either with LPS solution or with equal sterile saline. The results showed that AOP alleviated LPS-induced growth inhibition by prompting protein digestibility, and decreasing serum stress hormones and pro-inflammatory cytokines content of broilers. Moreover, AOP decreased LPS-induced over-production of IL-1β and IL-6 through suppressing TLR4/NF-κB pathway, and alleviated LPS-induced decreasing of T-AOC, CAT and GPx activities by activating Nrf2/Keap1 pathway, which ultimately improved jejunum morphology. In conclusion, AOP alleviated LPS-induced growth inhibition and intestinal damage by enhancing anti-inflammatory and antioxidant capacities of broilers.

Ginsenoside Rg1 modulates intestinal microbiota and supports re-generation of immune cells in dexamethasone-treated mice

Ginsenoside Rg1 is one of the major ginsenosides found in roots of Panax ginseng and Panax notoginseng. Ginsenoside Rg1 is known to possess various biological activities including immunity enhancement activity. However, it is not clear whether the regulation of immune function by Rg1 is related to the intestinal microbiota. In the present study, the immuno-modulatory and gut microbiota-reshaping effects of ginsenoside Rg1 were evaluated. Ginsenoside Rg1 acts as an immune-enhancing agent to increase spleen index and the number of T, B and dendritic cells in dexamethasone (Dex)-treated mice. Ginsenoside Rg1 also increased the production of sIgA and regulated the expression of interleukin 2 (IL-2), IL-4, IL-10 and IFN-γ. Meanwhile, Rg1 administration regulated the structure of intestinal microbiota. The relative abundance of mouse intestinal microbial groups, such as Alistipes, Ruminococcaceae, Lachnospiraceae, and Roseburia were increased by Rg1 administration, whereas a decrease in the potential pathogens like Helicobacteraceae, Dubosiella, Mycoplasma, Alloprevotella, Allobaculum was observed. Moreover, Rg1 metabolites of Lachnospiraceae bacterium enhanced the proliferation of CD4+ T cells and T regulatory (Treg) cells. Ginsenoside Rg1 improved the inflammatory condition of the colonic tissue and repaired the destructed mucosal barrier. This study suggested that Rg1 strengthens immunity with regulating the homeostasis of intestinal microbiota in mice.

Stimulating the Hematopoietic Effect of Simulated Digestive Product of Fucoidan from Sargassum fusiforme on Cyclophosphamide-Induced Hematopoietic Damage in Mice and Its Protective Mechanisms Based on Serum Lipidomics

Hematopoietic damage is a serious side effect of cytotoxic drugs, and agents promoting hematopoiesis are quite important for decreasing the death rate in cancer patients. In our previous work, we prepared the simulated digestive product of fucoidan from Sargassum fusiforme, DSFF, and found that DSFF could activate macrophages. However, more investigations are needed to further evaluate whether DSFF could promote hematopoiesis in the chemotherapy process. In this study, the protective effect of DSFF (1.8-7.2 mg/kg, i.p.) on cyclophosphamide-induced hematopoietic damage in mice and the underlying mechanisms were investigated. Our results show that DSFF could restore the numbers of white blood cells, neutrophils, and platelets in the peripheral blood, and could also retard bone marrow cell decrease in mice with cyclophosphamide-induced hematopoietic damage. UPLC/Q-Extraction Orbitrap/MS/MS-based lipidomics results reveal 16 potential lipid biomarkers in a serum that responded to hematopoietic damage in mice. Among them, PC (20:1/14:0) and SM (18:0/22:0) were the key lipid molecules through which DSFF exerted protective actions. In a validation experiment, DSFF (6.25-100 μg/mL) could also promote K562 cell proliferation and differentiation in vitro. The current findings indicated that DSFF could affect the blood cells and bone marrow cells in vivo and thus showed good potential and application value in alleviating the hematopoietic damage caused by cyclophosphamide.

Immune-Enhancing Effects of Crude Polysaccharides from Korean Ginseng Berries on Spleens of Mice with Cyclophosphamide-Induced Immunosuppression

Panax ginseng C. A. Meyer is well known as traditional herbal medicine, and ginseng berries are known to exhibit potential immune-enhancing functions. However, little is known about the in vivo immunomodulatory activity of Korean ginseng berries. In this study, crude Korean ginseng berries polysaccharides (GBP) were isolated and their immunomodulatory activities were investigated using cyclophosphamide (CY)-induced immunosuppressive BALB/c mice. In CY-treated mice, oral administration of GBP (50-500 mg/kg BW) remarkably increased their spleen sizes and spleen indices and activated NK cell activities. GBP also resulted in the proliferation of splenic lymphocytes (coordinating with ConA: plant mitogen which is known to stimulate T-cell or LPS: endotoxin which binds receptor complex in B cells to promote the secretion of pro-inflammatory cytokines) in a dose-dependent manner. In addition, GBP significantly stimulated mRNA expression levels of immune-associated genes including interleukin-1β (IL-1β), IL-2, IL-4, IL-6, tumor necrosis factor-α (TNF-α), interferon-γ (IFN-γ), toll-like receptor 4 (TLR-4), and cyclooxygenase-2 (COX-2) in CY-treated mice. These results indicate that GBP is involved in immune effects against CY-induced immunosuppression. Thus, GBP could be developed as an immunomodulation agent for medicinal or functional food application.

Structural characteristics and immunomodulatory effects of sulfated polysaccharides derived from marine algae

Marine algae are becoming an important source of valuable candidates of functional food that remain unexplored. Compositional analysis showed that marine algae contain essential nutrients, such as carbohydrates, proteins, fats, and minerals, of which polysaccharides are the main bioactive component. Depending on the source, marine algae polysaccharides are sulfated, which have diverse structures and compositions that influence their biological activities. A growing body of evidence has demonstrated that sulfated polysaccharides derived from marine algae (SPs) exhibit various bioactivities, especially immunomodulation. This review aims at summarizing the structural characteristics of SPs, their immunomodulatory effects, and the structural-immunomodulatory activity relationships between them from articles in recent decade, in order to provide a theoretical basis for the further applications of SPs as promising food or feed additives and possible health products to modulate the immune response.

Polysaccharides from Spores of Cordyceps cicadae Protect against Cyclophosphamide-Induced Immunosuppression and Oxidative Stress in Mice

This study investigated the purification, preliminary structure and in vivo immunomodulatory activities of polysaccharides from the spores of Cordyceps cicadae (CCSP). The crude CCSP was purified by diethylaminoethyl (DEAE)-cellulose and Sephadex G-100 chromatography, affording CCSP-1, CCSP-2 and CCSP-3 with molecular weights of 1.79 × 10⁶, 5.74 × 10⁴ and 7.93 × 10³ Da, respectively. CCSP-2 consisted of mannose and glucose, while CCSP-1 and CCSP-3 are composed of three and four monosaccharides with different molar ratios, respectively. CCSP-2 exhibited its ameliorative effects in cyclophosphamide-induced immunosuppressed mice through significantly increasing spleen and thymus indices, enhancing macrophage phagocytic activity, stimulating splenocyte proliferation, improving natural killer (NK) cytotoxicity, improving bone marrow suppression, regulating the secretion of cytokines and immunoglobulins, and modulating antioxidant enzyme system. These results indicate that CCSP-2 might be exploited as a promising natural immunomodulator.

Immunomodulatory and antioxidant effects of hydroxytyrosol in cyclophosphamide-induced immunosuppressed broilers

As an important olive component, hydroxytyrosol (HT) has good medicinal and health effects. However, its importance in alleviating immune suppression in broilers has not been established. Therefore, we aimed at evaluating the immunomodulatory and antioxidant effects of HT in immune suppressed broilers. Immune suppressed broiler models were established via intraperitoneal injection of 80 mg/kg cyclophosphamide (Cy). Thirty two Cobb 500 male broilers were randomly allocated into 4 groups of 8 each. Broilers in the model (Cy) and HT treatment (Cy+HT) groups were intraperitoneally administered with Cy (80 mg/kg BW) once a day for 3 d. From the 4th d, broilers in the Cy+HT and HT groups were treated with 0.5 mL of 200 mg/L HT solution, once a day, for 7 d. The Cy and Con groups were orally administered with normal saline. On the 14th and 28th d, serum and duodenal samples were obtained for testing. It was found that HT increased villi height (VH)/crypt depth (CD) ratio in the duodenum and suppressed serum tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6) levels. Moreover, it elevated the expressions of CD4+ and CD8+ T lymphocytes. HT upregulated the mRNA expression levels of interleukin-2 (IL-2), interleukin-4 (IL-4), and interleukin-10 (IL-10), enhanced the activity of superoxide dismutase (SOD), glutathione peroxidase (GSH-Px), and downregulated malondialdehyde (MDA) levels in Cy-induced immune-suppressed broilers. In conclusion, HT can alleviate immune-suppression as well as enhance immunity and antioxidant activities in the local mucosa of small intestines in broilers. Therefore, it can be used as an immune stimulant. More studies should be performed to confirm our findings and to elucidate on the mechanisms of HT.

Effects of simulated digestion in vitro on the structure and macrophages activation of fucoidan from Sargassum fusiforme

Molecular size and spatial structure affect the bioactivities of polysaccharides. SFF is a fucoidan extracted from Sargassum fusiforme. The possible changes of SFF affected by gastrointestinal tract and subsequently changes of its physicochemical property or its bioactivity have yet to be systematically investigated. Our results showed that DSFF, the gastrointestinal digestion product of SFF, has increased reducing sugar content, increased proportion of low molecular weight components, and a more clustered island-like morphology. Both SFF and DSFF activate RAW 264.7 macrophages evidenced by the increasing level of NO, intracellular ROS, and macrophages cytokines. Further investigation showed that DSFF induced M1 phenotype polarization in RAW 264.7 cells. DSFF also showed stronger macrophage activation and phenotype polarization than SFF. Our present work showed that SFF could be digested by simulated gastrointestinal environment in vitro and the digested product DSFF showed higher efficiency in macrophages activation and phenotype polarization.

Transcriptomic profile of human erythroleukemia cells in response to Sargassum fusiforme polysaccharide and its structure analysis

Sargassum fusiforme (S. fusiforme) has been used as an ingredient in Chinese herbal medicine for thousands of years. However, there are a limited number of studies concerning its therapeutic mechanism. High performance gel permeation chromatography (HPGPC) analysis showed that the average molecular weight of the S. fusiforme polysaccharide, SFPS 191212, is 43 kDa. SFPS 191212 is composed of mannose, rhamnose, galactose, xylose, glucose, and fucose (at a molar ratio: 2.1 : 2.9 : 1.8 : 15.5 : 4.6 : 62.5) with α- and β-configurations. The present research evaluated the anti-tumor potential of the S. fusiforme polysaccharide in human erythroleukemia (HEL) cells in vitro. To explore the SFPS 191212's apoptosis mechanism in HEL cells, transcriptome analysis was performed on HEL cells that were incubated with SFPS 191212. The inhibitory effect of SFPS 191212 on HEL cell growth was also analyzed. It was found that SFPS 191212 inhibited HEL cell proliferation, reduced cell viability in a concentration-dependent manner, and induced an insignificant toxic effect on normal human embryonic lung (MRC-5) cells. Compared with the control group, transcriptome analysis identified a total of 598 differentially expressed genes (DEGs), including 243 up-regulated genes and 355 down-regulated genes. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analyses were performed on all DEGs, and 900 GO terms and 52 pathways were found to be significantly enriched. Finally, 23 DEGs were randomly selected and confirmed by quantitative real-time polymerase chain reaction (qRT-PCR). Moreover, SFPS 191212 down-regulated the PI3K/Akt signal transduction pathway. Our results provide a framework for understanding the effect of SFPS 191212 on cancer cells and can serve as a resource for delineating the anti-tumor mechanisms of S. fusiforme.

Brown Seaweed Food Supplementation: Effects on Allergy and Inflammation and Its Consequences

Multiple health benefits have been ascribed to brown seaweeds that are used traditionally as dietary component mostly in Asia. This systematic review summarizes information on the impact of brown seaweeds or components on inflammation, and inflammation-related pathologies, such as allergies, diabetes mellitus and obesity. We focus on oral supplementation thus intending the use of brown seaweeds as food additives. Despite the great diversity of experimental systems in which distinct species and compounds were tested for their effects on inflammation and immunity, a remarkably homogeneous picture arises. The predominant effects of consumption of brown seaweeds or compounds can be classified into three categories: (1) inhibition of reactive oxygen species, known to be important drivers of inflammation; (2) regulation, i.e., in most cases inhibition of proinflammatory NF-κB signaling; (3) modulation of adaptive immune responses, in particular by interfering with T-helper cell polarization. Over the last decades, several inflammation-related diseases have increased substantially. These include allergies and autoimmune diseases as well as morbidities associated with lifestyle and aging. In this light, further development of brown seaweeds and seaweed compounds as functional foods and nutriceuticals might contribute to combat these challenges.

Structural Characterization and Immunomodulatory Activity of a Novel Polysaccharide From Lycopi Herba

Lycopi Herba has been broadly used as a traditional medicinal herb in Asia due to its ability to strengthen immunity. However, it is still obscure for its material basis and underlying mechanisms. Polysaccharide, as one of the most important components of most natural herbs, usually contributes to the immunomodulatory ability of herbs. Here, we aimed to detect polysaccharides from Lycopi Herba and examine their potential immunomodulatory activity. A novel polysaccharide (LHPW) was extracted from Lycopi Herba and purified by DEAE-52 cellulose chromatography and G-100 sephadex. According to physicochemical methods and monosaccharide composition analysis, LHPW was mainly composed of galactose, glucose, fructose, and arabinose. NMR and methylation analyses indicated that LHPW was a neutral polysaccharide with a backbone containing →3,6)-β-D-Galp-(1→, →4)-β-D-Galp-(1→ and →4)-α-D-Glcp-(1→, with the branches of →1)-β-D-Fruf-(2→ and →6)-α-D-Galp-(1→. Immunological tests indicated that LHPW could activate macrophage RAW264.7 and promote splenocyte proliferation. This study discovered a novel polysaccharide from Lycopi Herba and showed it was a potential immunomodulator.

Transcriptome Analysis Reveals Possible Immunomodulatory Activity Mechanism of Chlorella sp. Exopolysaccharides on RAW264.7 Macrophages

In this study, the exopolysaccharides of Chlorella sp. (CEP) were isolated to obtain the purified fraction CEP4. Characterization results showed that CEP4 was a sulfated heteropolysaccharide. The main monosaccharide components of CEP4 are glucosamine hydrochloride (40.8%) and glucuronic acid (21.0%). The impact of CEP4 on the immune activity of RAW264.7 macrophage cytokines was detected, and the results showed that CEP4 induced the production of nitric oxide (NO), TNF-α, and IL-6 in a dose-dependent pattern within a range of 6 μg/mL. A total of 4824 differentially expressed genes (DEGs) were obtained from the results of RNA-seq. Gene enrichment analysis showed that immune-related genes such as NFKB1, IL-6, and IL-1β were significantly upregulated, while the genes RIPK1 and TLR4 were significantly downregulated. KEGG pathway enrichment analysis showed that DEGs were significantly enriched in immune-related biological processes, including toll-like receptor (TLR) signaling pathway, cytosolic DNA-sensing pathway, and C-type lectin receptor signaling pathway. Protein–protein interaction (PPI) network analysis showed that HSP90AB1, Rbx1, ISG15, Psmb6, Psmb3, Psmb8, PSMA7, Polr2f, Rpsa, and NEDD8 were the hub genes with an essential role in the immune activity of CEP4. The preliminary results of the present study revealed the potential mechanism of CEP4 in the immune regulation of RAW264.7 macrophages, suggesting that CEP4 is a promising immunoregulatory agent.

Improvement of Myelopoiesis in Cyclophosphamide-Immunosuppressed Mice by Oral Administration of Viable or Non-Viable Lactobacillus Strains

Myelosuppression is the major dose-limiting toxicity of cancer chemotherapy. There have been many attempts to find new strategies that reduce myelosuppression. The dietary supplementation with lactic acid bacteria (LAB) improved respiratory innate immune response and the resistance against respiratory pathogens in immunosupressed hosts. Although LAB viability is an important factor in achieving optimal protective effects, non-viable LAB are capable of stimulating immunity. In this work, we studied the ability of oral preventive administration of viable and non-viable Lactobacillus rhamnosus CRL1505 or L. plantarum CRL1506 (Lr05, Lr05NV, Lp06V or Lp06NV, respectively) to minimize myelosuppressive and immunosuppressive effects derived from chemotherapy. Cyclophosphamide (Cy) impaired steady-state myelopoiesis in lactobacilli-treated and untreated control mice. Lr05V, Lr05NV and Lp06V treatments were the most effective to induce the early recovery of bone marrow (BM) tissue architecture, leukocytes, myeloid, pool mitotic and post-mitotic, peroxidase positive, and Gr-1^Low/High cells in BM. We selected the CRL1505 strain for being the one capable of maintaining its myelopoiesis-enhancing properties in its non-viable form. Although the CRL1505 treatments do not modify the Cy ability to induce apoptosis, both increased the incorporation of BrdU in BM cells. Consequently, Lr05NV and Lr05V treatments were able to promote early recovery of LSK cells (Lin^-Sca-1⁺c-Kit⁺ cells), multipotent progenitors (Lin^-Sca-1⁺c-Kit⁺CD34⁺ cells), and myeloid cells (Gr-1⁺Ly6G⁺Ly6C^- cells) with respect to the untreated Cy control. In addition, these treatments were able to increase the frequency of IL17A-producing innate lymphoid cells in the intestinal lamina propria (IL-17A⁺RORγt⁺CD4^-NKp46⁺ cells) after Cy injection. These results were correlated with an increase in the IL-17A serum levels, a GM-CSF high expression and a CXCL12 lower expression in BM. Therefore, both Lr05V and Lr05NV treatments are able to activate beneficially the IL-17A/GM-CSF axis and accelerate the recovery of Cy-induced immunosuppression by increasing BM myeloid precursors. We demonstrated for the first time the beneficial effect of CRL1505 strain on myelopoiesis affected by a chemotherapeutic drug. Furthermore, Lr05NV could be a good and safe resource for reducing chemotherapy-induced leukopenia. The results are a starting point for future research and open up broad prospects for future applications of the immunobiotics.

Inhibitory Effect of Sargassum fusiforme and Its Components on Replication of Respiratory Syncytial Virus In Vitro and In Vivo

Sargassum fusiforme, a plant used as a medicine and food, is regarded as a marine vegetable and health supplement to improve life expectancy. Here, we demonstrate that S. fusiforme extract (SFE) has antiviral effects against respiratory syncytial virus (RSV) in vitro and in vivo mouse model. Treatment of HEp2 cells with a non-cytotoxic concentration of SFE significantly reduced RSV replication, RSV-induced cell death, RSV gene transcription, RSV protein synthesis, and syncytium formation. Moreover, oral inoculation of SFE significantly improved RSV clearance from the lungs of BALB/c mice. Interestingly, the phenolic compounds eicosane, docosane, and tetracosane were identified as active components of SFE. Treatment with a non-cytotoxic concentration of these three components elicited similar antiviral effects against RSV infection as SFE in vitro. Together, these results suggest that SFE and its potential components are a promising natural antiviral agent candidate against RSV infection.

Neutral polysaccharide from Panax notoginseng enhanced cyclophosphamide antitumor efficacy in hepatoma H22-bearing mice

BACKGROUND

Our previous studies demonstrated that the administration of crude Polysaccharide from Panax notoginseng (CPPN) can effectively prolong the lifespan of tumor-bearing mice via boosting the host immune system as well as weak cytotoxicity against hepatocellular carcinoma (HCC). In the present study, Neutral Polysaccharide (NPPN) were further purified from crude polysaccharide isolated from panax notoginseng. The effects of NPPN on the immune function and hematopoietic function of mice with low immunity and myelosuppression induced by cyclophosphamide (CTX) were investigated. The effect of NPPN combined with CTX on the tumor inhibition rate of the H22 tumor-bearing mice and the impact of NPPN on the proliferation of H22 liver cancer cells in vitro were investigated.

METHODS

CPPN was obtained by water extraction and alcohol precipitation method, and further purified by DEAE Sepharose Fast Flow ion exchange resin column. NPPN was added to the immunosuppressed with myelosuppression mice induced by CTX. Thymus index, spleen index, lymphocyte proliferation stimulation index by adding of concanavalin A, determination of serum hemolysin, NK cell activity assay, mice carbon clearance experiment, blood count tests were detected. The tumor inhibition rate of the H22 tumor-bearing mice treated with NPPN combined with CTX was recorded.

RESULTS

NPPN and 4 kinds of acid polysaccharide from Panax notoginseng (APPN) were successfully isolated from the CPPN by DEAE Sepharose Fast Flow ion exchange resin column. NPPN inhibited the growth of H22 cells and significantly increase the tumor inhibition rate of the H22 tumor-bearing mice combined with CTX. The elevation of the cellular and humoral immunity levels as well as a variety of blood count tests indicators of immunosuppressive with myelosuppression mice may contribute to the antitumor activity of NPPN.

CONCLUSION

NPPN has a potential antitumor activity for the treatment of liver cancer combined with cyclophosphamide.

Protective effect of Polygonatum sibiricum polysaccharide on cyclophosphamide-induced immunosuppression in chickens

The purpose of the study was to evaluate the protective effects of polygonatum sibiricum polysaccharide (PP), an important component of rhizome polygonatum, on cyclophosphamide (CY) induced immunosuppressed chickens. Four hundred and eighty one-day-old Erlang mountainous chickens were randomly allocated into four treatments. The main factors consisted of dietary supplement (PP at 0 or 800 mg/kg of diet) and immunosuppressive challenge (birds challenged with CY or treated with sterile saline). The results showed that PP enhanced chickens' growth performance via elevating daily weight gain (DWG), serum protein production, and decreasing feed conversion ratio (FCR). Moreover, physical measurements revealed that PP accelerated recovery of relative weights of immune organs and maintained their structure and function. Biochemical analysis indicated that PP significantly stimulated immunoglobulin and antioxidant indexes in serum, and improved the proliferation of peripheral blood T lymphocytes. In addition, PP promoted immune organs cells to enter into S and G₂/M phases as well as inhibited the apoptosis in the spleen, thymus, and bursa of Fabricius. PP up regulated the expression of IL-2, IL-6 and IFN-γ genes. Therefore, PP performs a profile in antagonizing Cy-induced immunosuppression in chickens, and it seems that PP can be used as a potential immunostimulant agent.

A Comprehensive and Comparative Analysis of the Fucoidan Compositional Data Across the Phaeophyceae

In the current review, compositional data on fucoidans extracted from more than hundred different species were surveyed through the available literature. The analysis of crude extracts, purified extracts or carefully isolated fractions is included in tabular form, discriminating the seaweed source by its taxonomical order (and sometimes the family). This survey was able to encounter some similarities between the different species, as well as some differences. Fractions which were obtained through anion-exchange chromatography or cationic detergent precipitation showed the best separation patterns: the fractions with low charge correspond mostly to highly heterogeneous fucoidans, containing (besides fucose) other monosaccharides like xylose, galactose, mannose, rhamnose, and glucuronic acid, and contain low-sulfate/high uronic acid proportions, whereas those with higher total charge usually contain mainly fucose, accompanied with variable proportions of galactose, are highly sulfated and show almost no uronic acids. The latter fractions are usually the most biologically active. Fractions containing intermediate proportions of both polysaccharides appear at middle ionic strengths. This pattern is common for all the orders of brown seaweeds, and most differences appear from the seaweed source (habitat, season), and from the diverse extraction, purification, and analytitcal methods. The Dictyotales appear to be the most atypical order, as usually large proportions of mannose and uronic acids appear, and thus they obscure the differences between the fractions with different charge. Within the family Alariaceae (order Laminariales), the presence of sulfated galactofucans with high galactose content (almost equal to that of fucose) is especially noteworthy.

Effects of Polysaccharides From Auricularia auricula on the Immuno-Stimulatory Activity and Gut Microbiota in Immunosuppressed Mice Induced by Cyclophosphamide

Recently, the immuno-enhancing potential of polysaccharide from Auricularia auricula (AAP) has been an area of research interest. However, the immune-stimulatory activity and mechanisms of AAP in immunosuppressive mice treated with cyclophosphamide (CTX) are still poorly understood. This study aimed to evaluate the immuno-enhancing effects of AAP and mine its possible mechanisms. Firstly, polysaccharides were isolated from A. auricula and purified. Secondly, the immune-stimulatory activities of the first AAP fraction (AAP1) were evaluated in the CTX-treated mice. Results showed that AAP1 significantly enhanced immune organ indexes, remarkably stimulated IFN-γ, IL-2, IL-4, IL-10, and TNF-α levels in the serum, and dramatically up-regulated the mRNA levels of Claudin-1, Occludin and ZO-1. Compared to the CTX group, AAP1 administration restored the gut microbiota composition similar to that of the control group by decreasing the ratio of Firmicutes/Bacteroidetes and increasing the relative abundances of short-chain fatty acid-producing microbiota. This study provides useful information for its further application as an immune-stimulator in foods and drugs.

Immunostimulatory Effects of Polysaccharides from Spirulina platensis In Vivo and Vitro and Their Activation Mechanism on RAW246.7 Macrophages

In this study, Spirulina platensis (S.p.) polysaccharide (PSP) was obtained by ultrasonic-microwave-assisted extraction (UMAE) and purified by an aqueous two-phase system (ATPS). Two different methods were applied to purified Spirulina platensis (S.p.) polysaccharide (PSP), respectively, due to PSP as a complex multi-component system. Three polysaccharide fractions (PSP-1, PSP-2, and PSP-3) with different acidic groups were obtained after PSP was fractionated by the diethyl aminoethyl (DEAE)-52 cellulose chromatography, and two polysaccharide fractions (PSP-L and PSP-H) with different molecular weight were obtained by ultrafiltration centrifugation. The chemoprotective effects of PSP in cyclophosphamide (Cy) treated mice were investigated. The results showed that PSP could significantly increase spleen and thymus index, peripheral white blood cells (PWBC), and peripheral blood lymphocytes (PBL). The in vivo immunostimulatory assays demonstrated that PSP could in dose-dependent increase of TNF-α, IL-10, and IFN-γ production in sera. The in vitro immunostimulatory assays showed that PSP and its fractions (PSPs) could evidently enhance the proliferation of splenocytes and RAW 264.7 cells and increase the productions of nitric oxide (NO), tumor necrosis factor-α (TNF-α), and interleukin 6 (IL-6). PSPs could also enhance phagocytic activity of RAW 264.7 cells. The acidic polysaccharide fractions of PSP-2, PSP-3, and PSP-L with small molecular weight had the higher immunostimulatory activity. Signaling pathway research results indicated that PSP-L activated RAW264.7 cells through MAPKs, NF-κB signaling pathways via TLR4 receptor.

Therapeutic and nutraceutical potentials of a brown seaweed Sargassum fusiforme

Sargassum fusiforme, also known as Yangqicai () in Chinese and Hijiki in Japanese, is a brown seaweed that grows abundantly along the rocky coastlines of Asian countries such as Japan, Korea, and China. The first use of S. fusiforme as a traditional Chinese medicinal plant was recorded in the Shennong Bencao Jing, dated 200 AD. It was referred to as Haizao (seaweed), renowned for treating Yinglu (tumor-like induration), dysuria, and edema. Currently, it is commonly used in traditional cuisine as it is rich in dietary fiber and minerals such as calcium, iron, and magnesium. Owing to its health benefits, S. fusiforme remains popular in China, Korea, and Japan, as well as in the UK and in North America. Currently, there is a lack of research on S. fusiforme; thus, we review the therapeutic effects of S. fusiforme, such as anticancer, antiangiogenic, and antiviral effects, in vitro and in vivo as reported during the past two decades. This review may promote further research on the therapeutic uses of S. fusiforme. Furthermore, we discuss the processes and considerations involved in using drugs produced from marine sources.

Effect of Sargassum fusiforme polysaccharide on apoptosis and its possible mechanism in human erythroleukemia cells

This study aimed to investigate the effects of Sargassum fusiforme polysaccharide (SFPS I, II, and III) on the apoptosis and regulation of human erythroleukemia (HEL) cells. The effect of different doses of SFPS on HEL cell growth was detected using the Cell Counting Kit-8 method, and apoptosis was detected by Hoechst staining. Cell cycle distribution and apoptosis were detected using flow cytometry. Expression of the cell cycle gene, p53, antiapoptotic genes, Bcl-xL and Bcl-2, and pro-apoptotic genes, Bax, Bad, and Caspase-3, as well as the expression of the corresponding proteins, were detected using real-time quantitative polymerase chain reaction (qPCR) and Western blot. The results showed that SFPS II and III decreased HEL cell viability and induced HEL cell apoptosis. Different concentrations of SFPS (I, II, and III) were detected that induced much less toxic effect in normal human embryonic lung (MRC-5) cells, and SFPS I increased cell proliferation, indicating its favorable selectivity towards cancer cells. The mechanism by which SFPS induced apoptosis was also found to be related to the induction of cell cycle arrest in the G0/G1 phase and the increased expression of apoptosis-related genes and proteins. We concluded that SFPS induces HEL cell apoptosis, possibly via activation of the Caspase pathway, providing the theoretical basis for the development of SFPS-based anti-tumor drug products.

Effects of carboxymethyl chitosan oligosaccharide on regulating immunologic function and inhibiting tumor growth

Herein, the effects of carboxymethyl chitosan oligosaccharide (CM-COS) on regulating immunologic function and inhibiting hepatocellular tumor growth were evaluated. Results showed that CM-COS caused dramatic viability loss of hepatocellular carcinoma BEL-7402 with non-toxicity towards normal liver L-02 cells. CM-COS repressed tumor growth of hepatoma-22, and elevated the spleen index and thymus index of tumor-bearing mice. Contents of VEGF and MMP-9 were significantly down-regulated by CM-COS. Histological analyses revealed that CM-COS promoted tumor cell necrosis and produced no significant toxicity to spleen tissues. Moreover, expressions of Caspase-3 in tumor tissues and IL-2 in spleen tissues were significantly activated by CM-COS. Additionally, in vitro cell viability, phagocytic capability and NO production of mouse peritoneal macrophages exposed to CM-COS were significantly higher. CM-COS remarkably increased the in vivo phagocytosing capacity of peritoneal macrophages of Kunming mice. Taken together, our findings suggested that CM-COS might be potentially effective and non-toxic candidate as anti-hepatoma agents.

Dietary supplementation with polysaccharides from Ziziphus Jujuba cv. Pozao intervenes in immune response via regulating peripheral immunity and intestinal barrier function in cyclophosphamide-induced mice

Ziziphus Jujuba cv. Pozao has been consumed as a traditional fruit with regional characteristics in China for a long time; however, fewer studies on polysaccharides from Ziziphus Jujuba cv. Pozao (JP) have been documented. This study aimed to evaluate the effect of oral administration of JP on cyclophosphamide-induced ICR mice for 28 days. The results showed that oral administration of JP could significantly improve the lymphocyte proliferation in the spleen and decrease the proportion of CD3+ and CD4+ and the ratio of CD4+/CD8+ in cyclophosphamide-induced mice in a dose-dependent manner. JP treatment also increased the levels of IL-2, IL-4, IL-10, IFN-γ, and TNF-α in serum and the intestine, and the improvement effects were proportional to the dose of JP. Similarly, JP significantly increased the levels of IgA and SIgA, as well as the expressions of Claudin-1 and Occludin in the intestine. Particularly, the expressions of Claudin-1 and Occludin were the best in the M-JP group. Furthermore, JP positively regulated the gut microbiota as indicated by the enriched microbiota diversity. At the phylum level, the relative abundance of Firmicutes was significantly decreased by JP, while that of Bacteroidetes was increased by JP treatment. More importantly, the ratio of Firmicutes/Bacteroidetes was significantly increased. And a high dose of JP is the most effective. At the genus level, the abundances of the Bacteroidales-S24-7-group, Lachnospiraceae, Alloprevotella, Alistipes and Bacteroides were increased by JP treatment. These results provided evidence for the regulating effect of JP on the peripheral immunity and intestinal barrier function in cyclophosphamide-induced hypoimmune mice.

Effects of probiotic litchi juice on immunomodulatory function and gut microbiota in mice

Development new functional foods containing probiotics had gained much attention during the past two decades. In this study, probiotic litchi juice was developed, and its effects on immunomodulatory function and gut microbiota were evaluated. Firstly, the litchi juice was fermented with Lactobacillus casei, which increased total phenolic, total flavone, and exopolysaccharide contents of the litchi juice. Hence, the immunomodulatory influence of fermented litchi juice (FL) was investigated in cyclophosphamide-induced mice. The results showed that FL enhanced immune organs indexes (spleen, thymus) and antioxidant capacity, improved the secretions of cytokines (IL-2, IL-6) and immunoglobulins (IgA, IgG, SIgA), and protected the intestinal tract. Finally, the effect of FL on gut microbiota was analyzed by high-throughput sequencing analysis. The changes in the relative abundance of dominant microbe were investigated at phylum and genus levels, respectively. After treatment with FL, the relative abundance of Firmicutes phylum was dramatically increased, as well as the genera of Faecalibaculum, Lactobacillus, and Akkermansia. These findings indicated that probiotic litchi juice could alleviate immune dysfunction and modify gut microbiota structure of mice, which provide a potential functional food to improve the host health.

The structural characterization and immune modulation activitives comparison of Codonopsis pilosula polysaccharide (CPPS) and selenizing CPPS (sCPPS) on mouse in vitro and vivo

Codonopsis pilosula polysaccharide (CPPS) and selenizing CPPS (sCPPS) were prepared and identified by a combination of chemical and instrumental analysis. Their immune modulation activities were compared by lymphocyte proliferation and flowcytometry tests in vitro or serum antibody responses and cytokines with immunization against OVA mice in vivo. The results showed that the sCPPS was successfully modified in selenylation. In vitro, the sCPPS were more effective compared with CPPS in promoting lymphocyte proliferation synergistically with PHA or LPS and increasing the ratio of CD4+ to CD8 + T cells. In vivo, sCPPS could significantly raised IgG, IgM, IFN-γ, IL-2 and IL-4 contents in the serum of mouse against OVA in comparison with CPPS. These results indicate that selenylation modification can enhance the immune modulation activitives of CPPS. sCPPS would be as a component drug of new-type immunoenhancer.

Quality control and immunological activity of lentinan samples produced in China

Lentinan is widely used as a therapeutic agent for treatment of malignant tumors in clinical practice. The chemical structure of lentinan is highly associated with its biological activity. In this study, the correlation between the structure of lentinan and its immune activity was investigated to assess the function of key parameters that can influence quality control of lentinan. The results showed that the batch-to-batch consistency of two lentinan samples was satisfactory, indicating the stability of production process of lentinan. However, although the chemical composition and triple-helical conformation (THC) of the tested samples were relatively similar, their Mw, polydispersity index (PDI), and Rg_z remarkably varied due to different production processes. In vitro immunomodulatory assay reflects that lentinan could stimulate the macrophages phagocytic capacity. Meanwhile, lentinan samples could improve the spleen and thymus indices, promote the proliferation of lymphocytes and adjust for the percentages of CD4+ and CD8+ T cells in vivo. Furthermore, the immunomodulatory effect of lentinan sample B (Mw: 650,700 g/mol) was superior than that of the sample A (Mw: 4,818,700 g/mol). It was noted that the Mw should be detected as a necessary index for quality control of lentinan to ensure stability and effectiveness of the production process.

Structural analysis of a novel sulfated galacto-fuco-xylo-glucurono-mannan from Sargassum fusiforme and its anti-lung cancer activity

Polysaccharide (HFSGF) was purified from Sargassum fusiforme. Autohydrolysis and gel column chromatography were performed to fractionate HFSGF into three components (HFSGF-S, HFSGF-L and HFSGF-H). Compositional analysis, mass spectrometry and nuclear magnetic resonance spectroscopy were used to elucidate the structural features of HFSGF. HFSGF-S was a mixture of sulfated galacto-fuco-oligomers, from the branches terminal ends; in HFSGF-L, the branches of HFSGF, was a sulfated galactofucan, containing a backbone of 1,3-linked α-L-fucan sulfated at C2/4 and/or C4 and interspersed with galactose (Gal); and in HFSGF-H, the backbone of HFSGF, was composed of alternating 1,2-linked α-D-mannose (Man) and 1,4-linked β-D-glucuronic acid (GlcA), branched with sulfated galactofucan or sulfated fucan, 1,3-linked α-L-fucan sulfated at C2/4 and/or C4 and partly interspersed with Gal. Some fucose (Fuc) residues were also partially branched with xylose (Xyl). The anti-lung cancer activities of HFSGF-L and HFSGF-H against human lung cancer A549 cells in vitro and A549 xenograft tumor growth in vivo were determined. HFSGF-H had higher activity in vitro (IC50 ~12 mg/mL for 24 h) and in vivo (tumor inhibition ~51%.) than HFSGF-L, indicating that HFSGF-H might be a leading compound for a potential new therapeutics for the treatment of lung cancer.

Immune-modulating and anti-inflammatory marine compounds against cancer

The recent advances in cancer immunotherapy confirm the crucial role of the immune system in cancer progression and treatment. Chronic inflammation and reduced immune surveillance are both features of the tumor microenvironment. Strategies aimed at reverting pro-tumor inflammation and stimulating the antitumor immune components are being actively searched, and the anticancer effects of many candidate drugs have been linked to their ability to modulate the immune system. Marine organisms constitute a rich reservoir of new bioactive molecules; some of them have already been exploited for pharmaceutical use, whereas many others are undergoing clinical or preclinical investigations for the treatment of different diseases, including cancer. In this review, we will discuss the immune-modulatory properties of marine compounds for their potential use in cancer prevention and treatment and as possible tools in the context of cancer immunotherapy.

The immunostimulatory activity of polysaccharides from Glycyrrhiza uralensis

Background

The enhancement of immunity is very important for immunocompromised patients such as cancer patients with radiotherapy or chemotherapy. Glycyrrhiza uralensis has been used as food and medicine for a long history. G. uralensis polysaccharides (GUPS) were prepared and its immunostimulatory effects were investigated.

Methods

Human monocyte-derived dendritic cells (DCs) and murine bone marrow-derived DCs were treated with different concentrations of GUPS. The DCs maturation and cytokine production were analyzed by flow cytometry and ELISA, respectively. Inhibitors and Western blot were used to study the mechanism of GUPS. The immunostimulatory effects of GUPS were further evaluated by naïve mouse model and immunosuppressive mouse model induced by cyclophosphamide.

Results

GUPS significantly promoted the maturation and cytokine secretion of human monocyte-derived DCs and murine bone marrow-derived DCs through TLR4 and down-stream p38, JNK and NF-κB signaling pathways. Interestingly, the migration of GUPS treated-DCs to lymph node was increased. In the mouse model, GUPS increased IL-12 production in sera but not for TNF-α. Moreover, GUPS ameliorated the side effect of cyclophosphamide and improved the immunity of immunosuppressive mice induced by cyclophosphamide. These results suggested that GUPS might be used for cancer therapy to ameliorate the side effect of chemotherapy and enhance the immunity.

Composition, isolation, purification and biological activities of Sargassum fusiforme polysaccharides: A review

Sargassum fusiforme polysaccharides, acidic water-soluble polysaccharides extract from Sargassum fusiforme, are mainly composed of alginic acid, fucoidan and laminaran. Alginic acid is carboxyl-containing polysaccharide formed by joining β-D-mannuronic acid and α-L-guluronic acid through β-(1→4)/α-(1→4) glycosidic bond. Fucoidan, a natural water-soluble sulfated heteropolysaccharide with fucose and sulfuric acid groups as the core structure, is mainly linked by L-fucose through α-(1→3) glycosidic bond and has the strongest biological activity. Laminaran is mainly composed of β-D-glucose through β-(1→3) glycosidic bond linkage. Sargassum fusiforme polysaccharides have a variety of pharmacological activities, including antioxidant, anti-tumor, promoting immunity, anti-aging, prompting bone growth, lowering blood glucose, anti-coagulation, anti-virus, anti-bacteria, anti-fatigue, promoting growth and development, and skin protection. These activities are closely related to the functions of fucoidan in Sargassum fusiforme polysaccharides, which fucoidan is able to strengthen immune system and antioxidation in human body. In this review, the composition, the isolation and purification, and the biological activities of Sargassum fusiforme polysaccharides are discussed and can bereference for further study.