A polysaccharide extracted from Grifola frondosa enhances the anti-tumor activity of bone marrow-derived dendritic cell-based immunotherapy against murine colon cancer

Efficient production, structural characterization and bioactivity of an extracellular polysaccharide from Grifola frondosa endophytic Burkholderia sp

Endophytic bacteria Burkholderia sp. (GFB) was firstly identified and isolated from Grifola frondosa. An exopolysaccharide (GFB-MP) of GFB strain was obtained following fermentation optimization, resulting in a maximum yield of 11.36 g/L in 5 L fed-batch fermentation. GFB-MP (MW 432.05 kDa) comprised mainly galactose, glucose, and mannose with a ratio of 39.52:14.22:46.26, indicating a mannose-enriched polysaccharide. Methylation and NMR analysis revealed that GFB-MP consisted of the main chain that was repeat units →4)-α-D-Glcp-(1 → bonded →6)-β-D-Galp-1 → repeat units and three O-6-linked branched chains. Antibacterial activity suggested that GFB-MP can effectively inhibit food pathogen bacteria Listeria and Escherichia coli with inhibition ratios of 73.4 % and 81.6 %, respectively. In addition, GFB-MP exhibited remarkable growth-promoting activity on probiotics with >50 % increments of cell growth. This study demonstrates that GFB-MP has the potential for health-beneficial food. Knowledge of endophyte polysaccharides in G. frondosa is important to understand their physiological activities and symbiotic interactions.

Unveiling the full spectrum of maitake mushrooms: A comprehensive review of their medicinal, therapeutic, nutraceutical, and cosmetic potential

This literature review provides an up-to-date exploration of the multifaceted attributes of maitake mushrooms (Grifola frondosa), elucidating their bioactive phytochemicals and diverse health advantages, including their substantial role in supporting human health and potential incorporation into the medicinal industry. Carbohydrates and protein are the major constituents contributing to the dry weight of G. frondosa, taking up around 70-80 % and 13-21 %, respectively, with emerging research linking these constituents to various health benefits. By synthesising current research findings, this review emphasises the substantial role of maitake mushrooms in supporting human health and underscores their potential incorporation into the medicinal industry. To further advance our understanding, future research should delve into the mechanisms underlying their health-promoting effects, with a focus on conducting quantitative studies to elucidate physiological pathways and potential drug interactions. Additionally, exploring their integration into functional foods or nutraceuticals through quantitative assessments of bioavailability and efficacy will be crucial for maximising their therapeutic benefits. This review aims to provide comprehensive insights, catalysing further research and innovation in utilising maitake mushrooms for improved well-being and industry advancement.

Polysaccharides regulate Th1/Th2 balance: A new strategy for tumor immunotherapy

T helper (Th) cells have received extensive attention owing to their indispensable roles in anti-tumor immune responses. Th1 and Th2 cells are two key subsets of Th cells that exist in relative equilibrium through the secretion of cytokines that suppress their respective immune response. When the type of cytokine in the tumor microenvironment is altered, this equilibrium may be disrupted, leading to a shift from Th1 to Th2 immune response. Th1/Th2 imbalance is one of the decisive factors in the development of malignant tumors. Therefore, focusing on the balance of Th1/Th2 anti-tumor immune responses may enable future breakthroughs in cancer immunotherapy. Polysaccharides can regulate the imbalance between Th1 and Th2 cells and their characteristic cytokine profiles, thereby improving the tumor immune microenvironment. To our knowledge, this study is the most comprehensive assessment of the regulation of the tumor Th1/Th2 balance by polysaccharides. Herein, we systematically summarized the intrinsic molecular mechanisms of polysaccharides in the regulation of Th1 and Th2 cells to provide a new perspective and potential target drugs for improved anti-tumor immunity and delayed tumor progression.

Can Natural Products be Used to Overcome the Limitations of Colorectal Cancer Immunotherapy?

Colorectal cancer (CRC) is a common cancer of the digestive system that endangers human health. Immunotherapy is widely used in the treatment of patients with cancer. Some patients with dMMR/MSI-H CRC benefit from treatments that use immune checkpoint inhibitors, but most CRC patients are not sensitive to immunotherapy. Furthermore, internal resistance and immune escape lead to a reduced immunotherapy response. Therefore, the development of an effective combination therapy to improve the response rate to immunotherapy is a goal of cancer research. Natural products are potential candidates for comprehensive cancer treatments due to their wide range of immunomodulatory effects through multifactorial underlying mechanisms. In this review, we summarize the challenges in the treatment of CRC and assess the immunomodulatory effects of natural products and their active components. Our work suggests that natural products represent potential options for combined CRC immunotherapy.

In Vitro Anti-proliferative and Anti-invasive Effect of Polysaccharide-rich Extracts from Trametes Versicolor and Grifola Frondosa in Colon Cancer Cells

Colorectal cancer (CRC) is one of leading causes of mortality in western countries and novel treatment strategies are required. The medicinal application of mushrooms has been used in traditional medicine in many oriental countries. Polysaccharide-rich extracts obtained from certain medicinal mushroom species have shown antitumor effects in different experimental models. In the present study, we have developed polysaccharide-rich extracts from Trametes versicolor (TV) and Grifola frondosa (GF) fruit bodies. We aim to evaluate the anticancer effects of these polysaccharide-rich extracts in LoVo and HT-29 human colon cancer cells. The in vitro effects were determined by cytotoxicity assay, proliferation assay, wound healing assay and invasion assay. Moreover, the effect on anchorage independent-cell growth was also determined. Our results showed that TV and GF extracts did inhibit human colon cell proliferation and induce cytotoxicity. Furthermore, both fungal extracts significantly inhibited oncogenic potential, cell migration and invasion in colon cancer cells. In addition, extracts induce a more epithelial phenotype, observed by phase contrast images, together with an increase expression of the E-cadherin epithelial marker, detected by western-blotting analyses. Moreover, by using gelatin zymography assays, it was detected a decrease of MMP-2 enzyme activity, a crucial metalloproteinase important for the degradation of the extracellular matrix. Finally, the combination of the extracts with one the most clinical used agents for colorectal cancer, 5-fluorouracil, increases cell cytotoxicity. Taken together our results underscore a potential antitumor effect of polysaccharide-rich extracts obtained from TV and GF in human colon cancer cells lines. These finding may contribute to the reported health effects of fungal extracts.

A polysaccharide-peptide with mercury clearance activity from dried fruiting bodies of maitake mushroom Grifola frondosa

Mercury is considered to be “a global pollutant” and raises concern worldwide. Once mercury enters the body, it will be distributed all over the body but will accumulate in the brain, kidney and liver. To date, no substance originating from edible fungi capable of adsorbing mercury has been reported. We found that the mushroom Grifola frondosa exhibited mercury adsorption capacity. A polysaccharide-peptide (GFPP), displaying the unique N-terminal amino acid sequence of APPGMHQKQQ and 7 partial sequences with high reliability obtained by LC-MS/MS, was isolated by hot-water extraction of its fruiting bodies followed by ion exchange chromatography and gel filtration chromatography. Two rat models were employed to determine the dose and the duration of HgCl₂ treatment (given by acute administration or continuous treatment) to test if G. frondosa could promote mercury elimination. For rats subjected to acute treatment with HgCl₂, both GFPP and G. frondosa fruiting bodies (GFFF) could accelerate the decline of blood mercury level, which fell precipitously by 50% on the second day. GFPP and GFFF also promoted elimination of the burden of mercury in the liver and kidneys. For rats receiving continuous HgCl₂ treatment, G. frondosa prevented the progressive increase of blood mercury level, and kept the blood mercury level within a relatively stable range.

Green and Efficient PEG-Based Ultrasonic-Assisted Extraction of Polysaccharides from Tree Peony Pods and the Evaluation of Their Antioxidant Activity In Vitro

We adopted and developed an ultrasonic-assisted extraction method to obtain polysaccharides from tree peony pods using polyethylene glycol (PEG) as the solvent. The technological parameters have been designed as a single factor to enhance the tree peony pod polysaccharide extraction yield. Specific conditions (ultrasound irradiation power, 250 W; ultrasound irradiation time, 30 min; reaction temperature 50°C; liquid-solid ratio, 25 mL/g; and concentration of PEG, 0.2 g/mL) generated an experimental yield of 14.14%  ± 0.44%. Subsequently, the monosaccharide composition of the tree peony pod polysaccharides was determined by HPLC using a 1-phenyl-3-methyl-5-pyrazolone precolumn derivatization method. The results indicated that tree peony pod polysaccharides contained mannoses, rhamnose, glucuronic acid, galacturonic acid, glucose, galactose, arabinose, and fucose with a molar ratio of 1.44 : 2.87 : 0.32 : 18.99 : 3.99 : 10.21 : 0.96 : 1.85 : 0.21. The tree peony pod polysaccharides obtained are mainly galacturonic acid and galactose, which are acidic polysaccharides. Finally, the antioxidant activities (DPPH and FRAP) of the tree peony pod polysaccharides were assessed, and the compounds exhibited moderate antioxidant activities.

B-glucans from Grifola frondosa and Ganoderma lucidum in breast cancer: an example of complementary and integrative medicine

Culinary and medicinal mushrooms are widely used in Asian countries, both as dietary supplements and as nutraceutical foods. They have recently become popular in Europe, as well, for their nutritional and health benefits. In particular, epidemiological studies conducted in Asia suggest that mushroom intake, together with other phytotherapy substances, protects against cancer, specifically gastrointestinal (GI) and breast cancers. Most of the data come from in vitro studies and in vivo experimental animal models. Therefore, in order to translate the updated knowledge to clinical research (i.e., from bench to bedside) a systematic translational research program should be initiated. Future randomized controlled trials comparing the effects of G. frondosa and G. lucidum on conventional treatment outcomes are warranted. The purpose of this review was to describe the emerging mechanisms of action of the mushrooms' anticancer functions which makes their use in clinical practice so promising. Clinical effects of mycotherapy (specifically, the use of Ganoderma lucidum and Grifola frondosa) on long-term survival, tumor response, host immune functions, inflammation, and QoL in cancer patients were also addressed. Adverse events associated with mycotherapy were also investigated. Emerging data point to a potential role of G. lucidum for modulating the carcinogenic potential of GI microbiota, which suggests a new complementary and integrated approach to breast cancer treatment.

Antitumor activity of orally administered maitake α-glucan by stimulating antitumor immune response in murine tumor

Maitake α-glucan, YM-2A, isolated from Grifola frondosa, has been characterized as a highly α-1,6-branched α-1,4 glucan. YM-2A has been shown to possess an anti-virus effect in mice; however, it does not directly inhibit growth of the virus in vitro, indicating that the anti-virus effect of YM-2A might be associated with modulation of the host immune system. In this study, we found that oral administration of YM-2A could inhibit tumor growth and improve survival rate in two distinct mouse models of colon-26 carcinoma and B16 melanoma. Orally administered YM-2A enhanced antitumor immune response by increasing INF-γ-expressing CD4⁺ and CD8⁺ cells in the spleen and INF-γ-expressing CD8⁺ cells in tumor-draining lymph nodes. In vitro study showed that YM-2A directly activated splenic CD11b⁺ myeloid cells, peritoneal macrophages and bone marrow-derived dendritic cells, but did not affect splenic CD11b^- lymphocytes or colon-26 tumor cells. YM-2A is more slowly digested by pancreatic α-amylase than are amylopectin and rabbit liver glycogen, and orally administered YM-2A enhanced the expression of MHC class II and CD86 on dendritic cells and the expression of MHC class II on macrophages in Peyer’s patches. Furthermore, in vitro stimulation of YM-2A increased the expression of pro-inflammatory cytokines in Peyer’s patch CD11c⁺ cells. These results suggest that orally administered YM-2A can activate dendritic cells and macrophages in Peyer’s patches, inducing systemic antitumor T-cell response. Thus, YM-2A might be a candidate for an oral therapeutic agent in cancer immunotherapy.

Discovery of BVDU as a promising Drug for autoimmune diseases Therapy by Dendritic-cell-based functional screening

Dendritic cells (DCs) play a critical role in the pathogenesis of autoimmune diseases including multiple sclerosis, and targeting DCs’ cytokines production is an important strategy for autoimmune diseases treatment. By establishing a high-throughput screening system, we analyzed LOPAC drug library to identify drugs that control the secretion of IL-6 by DCs, we selected the most likely candidate drug, BVDU, and found that it affected not only IL-6 production, but also that of IL-12, IL-1β during the DCs differentiation and maturation. The mechanism studies showed that BVDU treatment restricted the phosphorylation of MAP kinase, which played an important role in DC cytokine production. We further assessed the in vivo therapeutic potentials of BVDU on mouse models including EAE and STZ-induced T1D, and found that BVDU treated EAE mice exhibited significantly lower EAE clinical scores, decreased leukocyte infiltration in central nervous system lesions, and reduced demyelination. As in T1D mice, BVDU treatment also showed promising therapeutic effects based on both alleviated disease symptoms and tissue pathogenesis. More interestingly, the modulating effect of BVDU on IL-6 production was further verified in human primary DCs. The above data supported the promising application of our screen model, and also the potential of BVDU for autoimmune diseases therapy.

In Vitro Effects of Some Botanicals with Anti-Inflammatory and Antitoxic Activity

Several extrinsic factors, like drugs and chemicals, can foster autoimmunity. Tetracyclines, in particular oxytetracycline (OTC), appear to correlate with the emergence of immune-mediated diseases. Accumulation of OTC, the elective drug for gastrointestinal and respiratory infectious disease treatment in broiler chickens, was reported in chicken edible tissues and could represent a potential risk for pets and humans that could assume this antibiotic as residue in meat or in meat-derived byproducts. We investigated the in vitro anti-inflammatory properties of a pool of thirteen botanicals as a part of a nutraceutical diet, with proven immunomodulatory activity. In addition, we evaluated the effect of such botanicals in contrasting the in vitro proinflammatory toxicity of OTC. Our results showed a significant reduction in interferon- (INF-) γ production by human and canine lymphocytes in presence of botanicals ((⁎) p < 0.05). Increased INF-γ production, dependent on 24-hour OTC-incubation of T lymphocytes, was significantly reduced by the coincubation with Haematococcus pluvialis, with Glycine max, and with the mix of all botanicals ((⁎) p < 0.05). In conclusion, the use of these botanicals was shown to be able to contrast OTC-toxicity and could represent a new approach for the development of functional foods useful to enhance the standard pharmacological treatment in infections as well as in preventing or reducing the emergence of inflammatory diseases.

Cold-water extracts of Grifola frondosa and its purified active fraction inhibit hepatocellular carcinoma in vitro and in vivo

Mushrooms are used in traditional Chinese medicine to treat a variety of diseases. Grifola frondosa (GF) is an edible mushroom indigenous to many Asian countries with a large fruiting body characterized by overlapping caps. In particular, GF is known for its anti-tumor activity, which has been targeted by scientific and clinical research. This study aimed to investigate the effects of the cold-water extract of GF (GFW) and its active fraction (GFW-GF) on autophagy and apoptosis, and the underlying mechanisms in vitro and in vivo Our results revealed that GFW and GFW-GF inhibited phosphatidylinositol 3-kinase (PI3K) and stimulated c-Jun N-terminal kinase (JNK) pathways, thereby inducing autophagy. We also demonstrated that GFW and GFW-GF inhibited proliferation, induced cell cycle arrest, and apoptosis in Hep3B hepatoma cells. GFW and GFW-GF markedly arrested cells in S phase and promoted cleavage of caspase-3 and -9. In addition, GFW and GFW-GF decreased the expression levels of the anti-apoptotic proteins protein kinase B and extracellular signal-regulated kinase. We also found that GFW significantly inhibited tumor growth in nude mice implanted with Hep3B cells. Our work demonstrates that GF and its active fraction inhibit hepatoma growth by inducing autophagy and apoptosis.

Soluble β-glucan from Grifola frondosa induces tumor regression in synergy with TLR9 agonist via dendritic cell-mediated immunity

The maturation of dendritic cells into more-immunostimulatory dendritic cells by stimulation with different combinations of immunologic agents is expected to provide efficient, adoptive immunotherapy against cancer. Soluble β-glucan maitake D-fraction, extracted from the maitake mushroom Grifola frondosa, acts as a potent immunotherapeutic agent, eliciting innate and adoptive immune responses, thereby contributing to its antitumor activity. Here, we evaluated the efficacy of maitake D-fraction, in combination with a Toll-like receptor agonist, to treat tumors in a murine model. Our results showed that maitake D-fraction, in combination with the Toll-like receptor 9 agonist, cytosine-phosphate-guanine oligodeoxynucleotide, synergistically increased the expression of dendritic cell maturation markers and interleukin-12 production in dendritic cells, but it did not increase interleukin-10 production, generating strong effector dendritic cells with an augmented capacity for efficiently priming an antigen-specific, T helper 1-type T cell response. Maitake D-fraction enhances cytosine-phosphate-guanine oligodeoxynucleotide-induced dendritic cell maturation and cytokine responses in a dectin-1-dependent pathway. We further showed that a combination therapy using cytosine-phosphate-guanine oligodeoxynucleotide and maitake D-fraction was highly effective, either as adjuvants for dendritic cell vaccination or by direct administration against murine tumor. Therapeutic responses to direct administration were associated with increased CD11c(+) dendritic cells in the tumor site and the induction of interferon-γ-producing CD4(+) and CD8(+) T cells. Our results indicate that maitake D-fraction and cytosine-phosphate-guanine oligodeoxynucleotide synergistically activated dendritic cells, resulting in tumor regression via an antitumor T helper cell 1-type response. Our findings provide the basis for a potent antitumor therapy using a novel combination of immunologic agents for future clinical immunotherapy studies in patients.

Expression of Fgf23 in activated dendritic cells and macrophages in response to immunological stimuli in mice

Fibroblast growth factors (Fgfs) are polypeptide growth factors with diverse biological activities. While several studies have revealed that Fgf23 plays important roles in the regulation of phosphate and vitamin D metabolism, the additional physiological roles of Fgf23 remain unclear. Although it is believed that osteoblasts/osteocytes are the main sources of Fgf23, we previously found that Fgf23 mRNA is also expressed in the mouse thymus, suggesting that it might be involved in the immune system. In this study we examined the potential roles of Fgf23 in immunological responses. Mouse serum Fgf23 levels were significantly increased following inoculation with Escherichia coli or Staphylococcus aureus or intraperitoneal injection of lipopolysaccharide. We also identified activated dendritic cells and macrophages that potentially contributed to increased serum Fgf23 levels. Nuclear factor-kappa B (NF-κB) signaling was essential for the induction of Fgf23 expression in dendritic cells in response to immunological stimuli. Moreover, we examined the effects of recombinant Fgf23 protein on immune cells in vitro. Fgfr1c, a potential receptor for Fgf23, was abundantly expressed in macrophages, suggesting that Fgf23 might be involved in signal transduction in these cells. Our data suggest that Fgf23 potentially increases the number in macrophages and induces expression of tumor necrosis factor-α (TNF-α), a proinflammatory cytokine. Collectively, these data suggest that Fgf23 might be intimately involved in inflammatory processes.

Ficus carica polysaccharides promote the maturation and function of dendritic cells

Various polysaccharides purified from plants are considered to be biological response modifiers and have been shown to enhance immune responses. Ficus carica L. is a Chinese traditional plant and has been widely used in Asian countries for its anti-tumor properties. Ficus carica polysaccharides (FCPS), one of the most essential and effective components in Ficus carica L., have been considered to be a beneficial immunomodulator and may be used in immunotherapy. However, the immunologic mechanism of FCPS is still unclear. Dectin-1 is a non-toll-like pattern recognition receptor, predominately expressed on dendritic cells (DCs). Activation of DCs through dectin-1 signaling can lead to the maturation of DC, thus inducing both innate and adaptive immune responses against tumor development and microbial infection. In our study, we found that FCPS could effectively stimulate DCs, partially through the dectin-1/Syk pathway, and promote their maturation, as shown by the up-regulation of CD40, CD80, CD86, and major histocompatibility complex II (MHCII). FCPS also enhanced the production of cytokines by DCs, including IL-12, IFN-γ, IL-6, and IL-23. Moreover, FCPS-treated DCs showed an enhanced capability to stimulate T cells and promote T cell proliferation. Altogether, these results demonstrate that FCPS are able to activate and maturate DCs, thereby up-regulating the immunostimulatory capacity of DCs, which leads to enhanced T cell responses.

The anti-lung cancer activity of SEP is mediated by the activation and cytotoxicity of NK cells via TLR2/4 in vivo

Strongylocentrotus nudus egg polysaccharide (SEP) has been reported to display antitumor activity. However, the effects of SEP and its underlying mechanism in the treatment of lung cancer remain unclear, particularly with an immunodeficient mouse model of human non-small cell lung cancer (NSCLC). In the present study, we investigated the anti-lung cancer effects of SEP and its underlying mechanism of action in both Lewis lung cancer (LLC)-bearing C57/BL6J mice and human NSCLC H460-bearing nude mice. Although SEP showed no inhibitory effects on tumor cells in vitro, it markedly stimulated the percentage of CD3-NK1.1(+) cells and natural killer (NK) cell cytotoxicity in the spleens of nude mice and C57/BL6J mice. In LLC-bearing mice, SEP not only inhibited tumor growth but also promoted NK-mediated cytotoxicity, the NK1.1(+) cell population, and IL-2 and IFN-γ secretion. SEP significantly suppressed H460 growth in nude mice, which was abrogated by the selective depletion of NK cells via the intraperitoneal injection of anti-asialo GM-1 antibodies. Furthermore, anti-TLR2/4 antibodies blocked both SEP and NK cell binding and SEP-induced perforin secretion. SEP-induced proliferation and IFN-γ secretion by NK cells in wild type mice were partially impaired in TLR2 or TLR4 knockout mice. These results suggest that SEP-promoted NK cytotoxicity, which was partially mediated via TLR2 and TLR4, was the main contributing factor to lung cancer inhibition in vivo and that SEP may be a potential immunotherapy candidate for the treatment of lung cancer.

Crude dietary polysaccharide fraction isolated from jackfruit enhances immune system activity in mice

Crude polysaccharides (PSs) were isolated from the fruit pulp of jackfruit, and their chemical composition determined and evaluated for an immune regulatory activity in mice. The PSs were isolated from water extracts of jackfruit pulp (JFP) using the ethanol precipitation method. The resulting precipitates were further purified by dialysis and protein depletion by the Sevage method. The phenol-sulfuric method was used to determine the content of the PSs. The composition of PSs was determined by the Sephadex-G200 column chromatography and high-performance liquid chromatography methods. The thymus index and macrophage phagocytic function methods in mice were used to evaluate the immune regulatory activity of JFP-PSs. The JFP-PSs content in jackfruit was about 21% (w/w) and the yield of crude PSs was 3.91%. The single molecular mass weight PS was the main constituent of JFP-PSs. The major monosaccharide residues were rhamnose, glucose, galactose, and arabinose. The JFP-PSs enhanced the thymus weight index and the phagocytic rate after 30 days of subchronic p.o. administration to mice at 4.5 mg/kg. The JFP contains single molecular PS and JFP-PS has immune-stimulating activities in mice. These data suggest that at least some of the traditional uses of JFP can be ascribed to its immunomodulatory effects.

Characterization of a novel maitake (Grifola frondosa) protein that activates natural killer and dendritic cells and enhances antitumor immunity in mice

Grifola frondosa, also known as maitake, is a culinary mushroom with immune-enhancing and antitumor effects. Numerous studies have investigated the activity of maitake polysaccharide extracts, but studies of maitake proteins are scarce. In this study, we purified and characterized a new G. frondosa protein, GFP, from maitake fruiting bodies. GFP is a nonglucan heterodimeric 83 kDa protein that consists of two 41 kDa subunits. GFP induced interferon-γ secretion by murine splenocytes and natural killer cells and activated the maturation of bone marrow-derived dendritic cells (BMDCs) via a TLR4-dependent mechanism. GFP-treated BMDCs promoted a Th1 response and exhibited significant antitumor activity when transferred into tumor-bearing mice. In conclusion, we are the first to reveal the critical role of GFP in modulating the immune response and to link the immune-enhancing effects of maitake to its antitumor activities.

Oral administration of soluble β-glucans extracted from Grifola frondosa induces systemic antitumor immune response and decreases immunosuppression in tumor-bearing mice

Maitake D (MD)-Fraction is a highly purified soluble β-glucan derived from Grifola frondosa (an oriental edible mushroom). Intraperitoneal (i.p.) injection of MD-Fraction has been reported to inhibit tumor growth via enhancement of the host immune system. In this study, we demonstrated that oral administration of MD-Fraction as well as i.p. injection significantly inhibited tumor growth in murine tumor models. After oral administration, MD-Fraction was not transferred to the blood in its free form but was captured by antigen-presenting cells such as macrophages and dendritic cells (DCs) present in the Peyer's patch. The captured MD-Fraction was then transported to the spleen, thereby inducing the systemic immune response. Our study showed that MD-Fraction directly induced DC maturation via a C-type lectin receptor dectin-1 pathway. The therapeutic response of orally administered MD-Fraction was associated with (i) induced systemic tumor-antigen specific T cell response via dectin-1-dependent activation of DCs, (ii) increased infiltration of the activated T cells into the tumor and (iii) decreased number of tumor-caused immunosuppressive cells such as regulatory T cells and myeloid-derived suppressor cells. Our preclinical study suggests that MD-Fraction is a useful oral therapeutic agent in the management of patients with cancer.

Rehmannia glutinosa polysaccharide induces maturation of murine bone marrow derived Dendritic cells (BMDCs)

Purified Rehmannia glutinosa polysaccharide (RGP) is used as functional foods for the prevention and treatment of various diseases. In this study, we examined the effects of RGP on phenotypic and functional maturation of murine bone marrow derived Dendritic cells (BMDCs). Phenotypic maturation of BMDCs was confirmed by conventional scanning electron microscopy (SEM), flow cytometry (FCM) and functional maturation by transmission electron microscopy (TEM), cytochemistry assay, Acid phosphatase (ACP) activity, FITC-dextran, bio-assay and enzyme linked immunosorbent assay (ELISA).We found that RGP up-regulated the expression of CD40, CD80, CD83, CD86 and MHC II molecules of BMDCs, down-regulated pinocytosis and phagocytosis activity, induced IL-12 and TNF-α production of BMDCs. It is therefore concluded that RGP can effectively promote the maturation of DCs. Our study provides evidence and rationale on using RGP in various clinical conditions to enhance host immunity and suggests RGP as a potent adjuvant for the design of DC-based vaccines.

Anticancer polysaccharides from natural resources: a review of recent research

Taking into account the rising trend of the incidence of cancers of various organs, effective therapies are urgently needed to control human malignancies. However, almost all of the chemotherapy drugs currently on the market cause serious side effects. Fortunately, several previous studies have shown that some non-toxic biological macromolecules, including polysaccharides and polysaccharide-protein complexes, possess anti-cancer activities or can increase the efficacy of conventional chemotherapy drugs. Based on these encouraging observations, a great deal of effort has been focused on discovering anti-cancer polysaccharides and complexes for the development of effective therapeutics for various human cancers. This review focuses on the advancements in the anti-cancer efficacy of various natural polysaccharides and polysaccharide complexes in the past 5 years. Most polysaccharides were tested using model systems, while several involved clinical trials.

Profiling of hepatic gene expression of mice fed with edible japanese mushrooms by DNA microarray analysis: comparison among Pleurotus ostreatus, Grifola frondosa, and Hypsizigus marmoreus

To compare and estimate the effects of dietary intake of three kinds of mushrooms (Pleurotus ostreatus, Grifola frondosa, and Hypsizigus marmoreus), mice were fed a diet containing 10-14% of each mushroom for 4 weeks. Triacylglycerol in the liver and plasma decreased and plasma cholesterol increased in the P. ostreatus-fed group compared with those in the control group. Cholesterol in the liver was lower in the G. frondosa-fed group than in the control group, but no changes were found in the H. marmoreus-fed group. DNA microarray analysis of the liver revealed differences of gene expression patterns among mushrooms. Ctp1a and Fabp families were upregulated in the P. ostreatus-fed group, which were considered to promote lipid transport and β-oxidation. In the G. frondosa-fed group, not only the gene involved in signal transduction of innate immunity via TLR3 and interferon but also virus resistance genes, such as Mx1, Rsad2, and Oas1, were upregulated.

Composition and mechanism of antitumor effects of Hericium erinaceus mushroom extracts in tumor-bearing mice

We investigated antitumor effects of the following four extracts of freeze-dried Hericium erinaceus mushrooms in Balb/c mice intracutaneously transplanted on the backs with CT-26 colon cancer cells: HWE, hot water extraction by boiling in water for 3 h; MWE, microwaving in 50% ethanol/water at 60 W for 3 min; and ACE and AKE, boiling in 1% HCl or 3% NaOH for 2 h. HWE and MWE with a higher content of β-glucans, determined by an assay kit, than ACE and MKE were active in all bioassays. Gas chromatography/mass spectrometry analyses showed the presence of 40, 27, 16, and 13 compounds, respectively, in the four extracts. Daily intraperitoneal (ip) injections of HWE and MWE for 2 weeks significantly reduced tumor weights by 38 and 41%. Tumor regressions were associated with changes in the following cancer biomarkers as compared to phosphate buffer (PBS)-treated control mice: 2.7- and 2.4-fold increases in cytolytic activity of splenic natural killer (NK) cells; restored nitric oxide production and phagocytosis in peritoneal macrophages to 95-98% of normal levels; ∼2-fold increase in released pro-inflammatory cytokines tumor necrosis factor-α, interleukin-1β, and interleukin-6 from macrophages; and ∼56 and ∼60% reductions in the number of blood vessels inside the tumor. The pro-angiogenic factors vascular endothelial growth factor (VEGF), cyclooxygenase 2 (COX-2), and 5-lipoxygenase (5-LOX) were also significantly reduced in mRNA and protein expression by tumor genes. Enzyme-linked immunosorbent assay of tumor cells confirmed reduced expression of COX-2 and 5-LOX (32 and 31%). Reduced COX-2 and 5-LOX expression down-regulated VEGF expression, resulting in inhibition of neo-angiogenesis inside the tumors. The results indicate that induction of NK activity, activation of macrophages, and inhibition of angiogenesis all contribute to the mechanism of reduction of tumor size.