Low-molecular-weight polysaccharides from Agaricus blazei Murrill modulate the Th1 response in cancer immunity

Polysaccharide Isolated from Agaricus blazei Murill Alleviates Intestinal Ischemia/Reperfusion Injury through Regulating Gut Microbiota and Mitigating Inflammation in Mice

Intestinal ischemia-reperfusion (I/R) injury is a serious disease in medical settings, and gut dysbiosis is a major contributor to its development. Polysaccharides from Agaricus blazei Murill (ABM) showed a range of pharmacological activities, yet no studies assessed the potential of ABM polysaccharides for alleviating intestinal I/R injury. Here, we purified a major polysaccharide (ABP1) from an ABM fruit body and subsequently tested its potential to mitigate intestinal I/R injury in a mouse model of temporary superior mesenteric artery occlusion. The results reveal that ABP1 pretreatment enhances gut barrier function via upregulation of the expression of tight junction proteins such as ZO-1 and occludin. Additionally, ABP1 intervention reduces the recruitment of neutrophils and the polarization of M1 macrophages and limits inflammation by blocking the assembly of the NLRP3 inflammasome. Moreover, the role of ABP1 in regulating the gut microbiota was confirmed via antibiotic treatment. The omics data reveals that ABP1 reprograms gut microbiota compositions, characterized by a decrease of Proteobacteria and an increase of Lachnospiraceae and Lactobacillaceae, especially the SCFA-producing genera such as Ligilactobacillus and Blautia. Overall, this work highlights the therapeutic potential of ABP1 against intestinal I/R injury, which mainly exhibits its effects via regulating the gut microbiota and suppressing the overactivated inflammation response.

Agaricus blazei Polysaccharide Alleviates DSS-Induced Colitis in Mice by Modulating Intestinal Barrier and Remodeling Metabolism

Ulcerative colitis (UC) is a chronic noninfectious intestinal disease that severely affects patients' quality of life. Agaricus blazei Murrill polysaccharide (ABP) is an effective active ingredient extracted from Agaricus blazei Murrill (ABM). It has good efficacy in inhibiting tumor cell growth, lowering blood pressure, and improving atherosclerosis. However, its effect on colitis is unclear. The aim of this study was to analyze the protective effects and potential mechanisms of ABP against dextran sulfate sodium (DSS)-induced acute colitis in mice. The results showed that dietary supplementation with ABP significantly alleviated DSS-induced colitis symptoms, inflammatory responses, and oxidative stress. Meanwhile, ABP intervention was able to maintain the integrity of the intestinal mechanical barrier by promoting the expression of ZO-1 and Occludin tight junction proteins and facilitating mucus secretion. Moreover, 16S rRNA sequencing results suggested that ABP intervention was able to alleviate DSS-induced gut microbiota disruption, and nontargeted metabolomics results indicated that ABP was able to remodel metabolism. In conclusion, these results demonstrate that dietary supplementation with ABP alleviated DSS-induced acute colitis by maintaining intestinal barrier integrity and remodeling metabolism. These results improve our understanding of ABP function and provide a theoretical basis for the use of dietary supplementation with ABP for the prevention of ulcerative colitis.

Subcritical Water Extracts from Agaricus blazei Murrill's Mycelium Inhibit the Expression of Immune Checkpoint Molecules and Axl Receptor

Agaricus blazei Murrill or Himematsutake is an edible and medicinal mushroom. Agaricus blazei Murrill’s fruiting body extracts have anticancer properties, although the mechanism is unknown. Basic or organic solvents, which are hazardous for human health, are generally used to prepare Agaricus blazei Murrill’s extracts. The inhibition of immune checkpoint molecules and Axl receptor is an effective therapy in cancer. This study assessed whether subcritical water extracts of the Agaricus blazei Murrill’s fruiting body or mycelium affect the expression of Axl and immune checkpoint molecules in lung cancer cells. We used A549 cells and mouse bone marrow-derived dendritic cells in the experiments. We prepared subcritical water extracts from the Agaricus blazei Murrill’s fruiting body or mycelium. The subcritical water extracts from the Agaricus blazei Murrill’s fruiting body or mycelium significantly inhibited the expression of immune checkpoint molecules and Axl compared to saline-treated cells. Additionally, the hot water extract, subcritical water extract, and the hot water extraction residue subcritical water extract from the Agaricus blazei Murrill’s mycelium significantly enhanced the expression of maturation markers in dendritic cells. These observations suggest that the subcritical water extract from Agaricus blazei Murrill’s mycelium is a promising therapeutic tool for stimulating the immune response in cancer.

Medicinal Plants and Isolated Molecules Demonstrating Immunomodulation Activity as Potential Alternative Therapies for Viral Diseases Including COVID-19

Plants have been extensively studied since ancient times and numerous important chemical constituents with tremendous therapeutic potential are identified. Attacks of microorganisms including viruses and bacteria can be counteracted with an efficient immune system and therefore, stimulation of body’s defense mechanism against infections has been proven to be an effective approach. Polysaccharides, terpenoids, flavonoids, alkaloids, glycosides, and lactones are the important phytochemicals, reported to be primarily responsible for immunomodulation activity of the plants. These phytochemicals may act as lead molecules for the development of safe and effective immunomodulators as potential remedies for the prevention and cure of viral diseases. Natural products are known to primarily modulate the immune system in nonspecific ways. A number of plant-based principles have been identified and isolated with potential immunomodulation activity which justify their use in traditional folklore medicine and can form the basis of further specified research. The aim of the current review is to describe and highlight the immunomodulation potential of certain plants along with their bioactive chemical constituents. Relevant literatures of recent years were searched from commonly employed scientific databases on the basis of their ethnopharmacological use. Most of the plants displaying considerable immunomodulation activity are summarized along with their possible mechanisms. These discussions shall hopefully elicit the attention of researchers and encourage further studies on these plant-based immunomodulation products as potential therapy for the management of infectious diseases, including viral ones such as COVID-19.

Escherichia coli Heat-Labile Enterotoxin B Subunit Combined with Ginsenoside Rg1 as an Intranasal Adjuvant Triggers Type I Interferon Signaling Pathway and Enhances Adaptive Immune Responses to an Inactivated PRRSV Vaccine in ICR Mice

Porcine reproductive and respiratory syndrome virus (PRRSV) is a major pathogen that has threatened the global swine industry for almost 30 years. Because current vaccines do not provide complete protection, exploration of new preventive strategies is urgently needed. Here, we combined a heat-labile enterotoxin B subunit of Escherichia coli (LTB) and ginsenoside Rg1 to form an intranasal adjuvant and evaluated its enhancement of immune responses in mice when added to an inactivated-PRRSV vaccine. The combination adjuvant synergistically elicited higher neutralizing and non-neutralizing (immunoglobulin G and A) antibody responses in the circulatory system and respiratory tract, and enhanced T and B lymphocyte proliferation, CD4⁺ T-cell priming, and cytotoxic CD4⁺ T cell activities in mononuclear cells from spleen and lung tissues when compared to the PRRSV vaccine alone, and it resulted in balanced Th1/Th2/Th17 responses. More importantly, we observed that the combination adjuvant also up-regulated type I interferon signaling, which may contribute to improvement in adaptive immune responses. These results highlight the potential value of a combined adjuvant approach for improving the efficacy of vaccination against PRRSV. Further study is required to evaluate the efficacy of this combined adjuvant in swine.

A Solution with Ginseng Saponins and Selenium as Vaccine Diluent to Increase Th1/Th2 Immune Responses in Mice

Pseudorabies is an important infectious disease of swine, and immunization using attenuated pseudorabies virus (aPrV) vaccine is a routine practice to control this disease in swine herds. This study was to evaluate a saline solution containing ginseng stem-leaf saponins (GSLS) and sodium selenite (Se) as a vaccine adjuvant for its enhancement of immune response to aPrV vaccine. The results showed that aPrV vaccine diluted with saline containing GSLS-Se (aP-GSe) induced significantly higher immune responses than that of the vaccine diluted with saline alone (aP-S). The aP-GSe promoted higher production of gB-specific IgG, IgG1, and IgG2a, neutralizing antibody titers, secretion of Th1-type (IFN-γ, IL-2, IL-12), and Th2-type (IL-4, IL-6, IL-10) cytokines, and upregulated the T-bet/GATA-3 mRNA expression when compared to aP-S. In addition, cytolytic activity of NK cells, lymphocyte proliferation, and CD4⁺/CD8⁺ ratio was also significantly increased by aP-GSe. More importantly, aP-GSe conferred a much higher resistance of mice to a field virulent pseudorabies virus (fPrV) challenge. As the present study was conducted in mice, further study is required to evaluate the aP-GSe to improve the vaccination against PrV in swine.

Early IgG Response to Foot and Mouth Disease Vaccine Formulated with a Vegetable Oil Adjuvant

The present study evaluated soybean oil (SO) containing vitamin E (VE) and ginseng saponins (GS) (SO-VE-GS) for their adjuvant effect on foot-and-mouth disease (FMD) vaccine. Since mineral oil ISA 206 is a common adjuvant used in the FMD vaccine, it was used as a control adjuvant in this study. VE and GS were found to have a synergistic adjuvant effect. When mice were immunized with the FMD vaccine emulsified in SO with VE and GS, significantly higher serum IgG, IgG1, and IgG2a were found than VE and GS used alone. SO-VE-GS and ISA 206 behaved differently in adjuvant activities. When mice were immunized with the FMD vaccine adjuvanted with SO-VE-GS, significantly higher and earlier production of serum IgG was found than that adjuvanted with ISA 206. Although both adjuvants significantly increased the number of bone marrow plasma cells, a stimulation index of lymphocytes (SI) as well as the production of IL-4 and IL-6, SO-VE-GS promoted significantly higher SI and the ratio of CD4⁺/CD8⁺ T cells with production of increased IFN-γ and decreased TGF-β1 as compared with the ISA 206 group. The data suggested that SO-VE-GS activated Th1/Th2 immune responses. Transcriptome analysis of splenocytes showed that differentially expressed genes (DEGs), immune-related gene ontology (GO) terms, and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways were significantly enriched in the SO-VE-GS group. Therefore, the potent adjuvant effect of SO-VE-GS on the FMD vaccine may be attributed to the immune-related gene profile expressed in lymphocytes. Due to its plant origin and due to being much cheaper than imported mineral oil ISA 206, SO-VE-GS deserves further study in relation to vaccines used in food animals.

Historical and current perspectives on therapeutic potential of higher basidiomycetes: an overview

Mushrooms are macroscopic fungi which can be either epigeous or hypogeous and is estimated to be 140,000 on earth, yet only 10% are known. Since ancient time, it played a diverse role in human history for mycolatry, mycophagy and as medicine in folklore and religion. Many Asian and western countries consider mushrooms as panacea for a large number of diseases and utilized for consumption as a gourmet food for its taste as well as flavor. In recent years, scientific research fraternities have confirmed that various extracts and metabolites of mushrooms used traditionally are able to treat a wide range of diseases due to their balanced modulation of multiple targets thereby providing a greater therapeutic effect or equivalent curative effect to that of modern medicine. Medicinal mushrooms especially those belonging to higher basidiomycete groups are reservoir of bioactive compounds with multiple therapeutic properties. The present review provides historical importance as well as an updated information on pharmacologically relevant higher basidiomycetes belong to the genus Agaricus, Auricularia, Phellinus, Ganoderma, Pleurotus, Trametes and Lentinus and their biologically active secondary metabolites. This will help the researchers to understand various type of secondary metabolites, their therapeutic role and related in vivo or in vitro work at a glance. The mounting evidences from several scientific community across the globe, regarding various therapeutic applications of mushroom extracts, unarguably make it an advance research area worth mass attention.

PKHB1 Tumor Cell Lysate Induces Antitumor Immune System Stimulation and Tumor Regression in Syngeneic Mice with Tumoral T Lymphoblasts

Acute lymphocytic leukemia (ALL) is the most common pediatric cancer. Currently, treatment options for patients with relapsed and refractory ALL mostly rely on immunotherapies. However, hematological cancers are commonly associated with a low immunogenicity and immune tolerance, which may contribute to leukemia relapse and the difficulties associated with the development of effective immunotherapies against this disease. We recently demonstrated that PKHB1, a TSP1-derived CD47 agonist peptide, induces immunogenic cell death (ICD) in T cell ALL (T-ALL). Cell death induced by PKHB1 on T-ALL cell lines and their homologous murine, L5178Y-R (T-murine tumor lymphoblast cell line), induced damage-associated molecular patterns (DAMPs) exposure and release. Additionally, a prophylactic vaccination with PKHB1-treated L5178Y-R cells prevented tumor establishment in vivo in all the cases. Due to the immunogenic potential of PKHB1-treated cells, in this study we assessed their ability to induce antitumor immune responses ex vivo and in vivo in an established tumor. We first confirmed the selectivity of cell death induced by PKBH1 in tumor L5178Y-R cells and observed that calreticulin exposure increased when cell death increased. Then, we found that the tumor cell lysate (TCL) obtained from PKHB1-treated L5178YR tumor cells (PKHB1-TCL) was able to induce, ex vivo, dendritic cells maturation, cytokine production, and T cell antitumor responses. Finally, our results show that in vivo, PKHB1-TCL treatment induces tumor regression in syngeneic mice transplanted with L5178Y-R cells, increasing their overall survival and protecting them from further tumor establishment after tumor rechallenge. Altogether our results highlight the immunogenicity of the cell death induced by PKHB1 activation of CD47 as a potential therapeutic tool to overcome the low immunogenicity and immune tolerance in T-ALL.

Cistanche tubulosa phenylethanoid glycosides induce apoptosis in Eca-109 cells via the mitochondria-dependent pathway

Cistanche tubulosa has various biological functions. In the present study, the antitumor effect of water-soluble phenylethanoid glycosides of C. tubulosa (CTPG-W) on esophageal cancer was investigated. Eca-109 cells were treated with CTPG-W and the cell viability was measured by MTT assay. The apoptosis, cell cycle, mitochondrial membrane potential (Δψm) and reactive oxygen species were analyzed by flow cytometry. The levels of proteins in apoptotic pathways were detected by western blot analysis. It was determined that CTPG-W significantly reduced the viability of Eca-109 cells through the induction of apoptosis and cell cycle arrest. Following CTPG-W treatment, the Δψm of Eca-109 was notably decreased, which is associated with the upregulated levels of B-cell lymphoma-2 (Bcl-2)-associated X and downregulated levels of Bcl-2. Consequently, the levels of cytochrome c and c-Jun NH₂-terminal kinase were increased, which upregulated the levels of cleaved-poly (ADP-ribose) polymerase and cleaved-caspase-3, −7 and −9, but not caspase-8. Correspondingly, the levels of reactive oxygen species in Eca-109 cells demonstrated notable changes. These results indicated that CTPG-W induced apoptosis of Eca-109 cells through a mitochondrial-dependent pathway.