Tremella Polysaccharides attenuated sepsis through inhibiting abnormal CD4+CD25high regulatory T cells in mice

Tremella fuciformis polysaccharide reduces obesity in high-fat diet-fed mice by modulation of gut microbiota

Obesity is a metabolic disease associated with gut microbiota and low-grade chronic inflammation. Tremella fuciformis is a medicinal and edible fungus; polysaccharide (TP) is the main active component, which has a variety of biological activities, such as hypoglycemic and hypolipidemic. However, the anti-obesity effects and potential mechanisms of TP have never been reported. This study was conducted to elucidate the inhibitory effect of TP on high-fat diet (HFD)-induced obesity in mice. Mice were split into five groups: normal chow diet (NCD) group, NCD_TP_H group, HFD group, HFD_TP_L group and HFD_TP_H group. Our study showed that TP inhibited high-fat diet-induced weight gain and fat accumulation in mice and reduced blood glucose, hyperlipidemia and inflammation. TP also improved gut microbiota disorders by reducing the Firmicutes/Bacteroidetes ratio and modulating the relative abundance of specific gut microbiota. We also found that the anti-obesity and gut microbiota-modulating effects of TP could be transferred to HFD-fed mice via faecal microbiota transplantation (FMT), confirming that the gut microbiota was one of the targets of TP for obesity inhibition. Further studies showed that TP increased the production of short-chain fatty acids and the secretion of intestinal hormones. Our studies showed that TP inhibited obesity by modulating inflammation and the microbe-gut-brain axis, providing a rationale for developing TP to treat obesity and its complications.

An Immunological Polysaccharide from Tremella fuciformis: Essential Role of Acetylation in Immunomodulation

The edible fungus Tremella fuciformis was shown to have a high molecular weight (1.87 × 10³ kDa) bioactive polysaccharide, denoted as TFP-F1. Monosaccharide composition and NMR analysis of the polysaccharide and its derivatives indicated it contained fucose (Fucp), xylose (Xylp), mannose (Manp), and glucuronic acid (GlcAp) in a ratio of 0.9:1.0:3.2:1.2. Using IR, NMR, and GC-MS spectroscopic data, the structure of TFP-F1 was elucidated as {→3)-[β-D-GlcAp-(1→2)]-α-D-Manp-(1→3)-α-D-Manp-(1→3)-[α-L-Fucp-(1→2)-β-D-Xylp-(1→2)]-α-D-Manp-(1→}_n, with partial acetylation of C6-OH in mannoses. Furthermore, at a concentration of 1 μg/mL, TFP-F1 was found to stimulate the secretion of TNF-α and IL-6 in J774A.1 macrophage cells in vitro via interaction with toll-like receptor 4 (TLR4). The removal of O-acetyl groups led to the loss of immunomodulatory activities, demonstrating that O-acetyl groups play an essential role in enhancing the production of pro-inflammatory cytokines.

Extraction, isolation, purification, derivatization, bioactivity, structure-activity relationship and application of polysaccharides from white jellyfungus

White jellyfungus is one of the most popular nutritional supplements. The polysaccharide (WJP) is an important active component of white jellyfungus, it not only has a variety of biological activities but also is non-toxic to humans. So, many scholars have carried out different researches on WJP. However, the lack of a detailed summary of WJP limits the scale of industrial development of WJP. Herein, the research progress of WJP in extraction, isolation, structure, derivatization and structure-activity relationship was reviewed. Different extraction methods were compared, the activity and application of WJP were summarized, and the structure-activity relationship of WJP was emphasized in order to provide effective theoretical support for improving the utilization of WJP and promoting the application of related industries. This article is protected by copyright. All rights reserved.

Classification, structure and mechanism of antiviral polysaccharides derived from edible and medicinal fungus

The deficiency of chemical-synthesized antiviral drugs when applied in clinical therapy, such as drug resistance, and the lack of effective antiviral drugs to treat some newly emerging virus infections, such as COVID-19, promote the demand of novelty and safety anti-virus drug candidate from natural functional ingredient. Numerous studies have shown that some polysaccharides sourcing from edible and medicinal fungus (EMFs) exert direct or indirect anti-viral capacities. However, the internal connection of fungus type, polysaccharides structural characteristics, action mechanism was still unclear. Herein, our review focus on the two aspects, on the one hand, we discussed the type of anti-viral EMFs and the structural characteristics of polysaccharides to clarify the structure-activity relationship, on the other hand, the directly or indirectly antiviral mechanism of EMFs polysaccharides, including virus function suppression, immune-modulatory activity, anti-inflammatory activity, regulation of population balance of gut microbiota have been concluded to provide a comprehensive theory basis for better clinical utilization of EMFs polysaccharides as anti-viral agents.

A review on the production, structure, bioactivities and applications of Tremella polysaccharides

Tremella polysaccharide is known to be structurally unique and biologically active natural products, abundant and versatile in activities and applications in food industry, daily chemical industry and medicine industry. In order to improve the industrialisation of Tremella polysaccharide, the limitations of preparation and structure-activity relationship of Tremella polysaccharide were reviewed in this paper. The research progress of Tremella polysaccharide in the past 20 years was summarized from the sources, preparation methods, molecular structure, activity and application, and the research trend in the future was also prospected. The application prospect of Tremella polysaccharide in against multiple sub-health states was worth expecting.

Tremella fuciformis Polysaccharides Inhibited Colonic Inflammation in Dextran Sulfate Sodium-Treated Mice via Foxp3+ T Cells, Gut Microbiota, and Bacterial Metabolites

Tremella fuciformis is an edible medicinal mushroom, and its polysaccharide components are found to confer various health benefits. This study identified the protective effects of polysaccharides of Tremella fuciformis (TPs) against dextran sulfate sodium (DSS)-induced colitis in mice. High dose of TPs (HTPs) could prevent the colon from shortening, reduce activity of colonic myeloperoxidase and serum diamine oxidase (DAO), decrease the concentration of D-lactate, and alleviate the colonic tissue damage in colitic mice. HTPs treatment stimulated Foxp3+T cells, and promoted the production of anti-inflammatory cytokines whereas it reduced the production of pro-inflammatory and the portion of immunoglobulin A (IgA)-coated bacteria, which was related to modulation of immune responses. 16S rRNA sequencing analysis showed that TPs could significantly increase gut community diversity, and restore the relative abundances of Lactobacillus, Odoribacter, Helicobacter, Ruminococcaceae, and Marinifilaceae. According to metabolomic analysis, HTPs induced specific microbial metabolites akin to that in normal mice. Tyrosine biosynthesis, tryptophan metabolism, and bile acid metabolism were influenced in the HTPs group compared with those in the DSS group. HTPs could alleviate DSS-induced colitis by immunoregulation and restored the gut microbiota and microbial metabolites. The results indicated that HTPs have potential to be developed as a food supplement to ameliorate intestinal diseases.

Plackett–Burman Combined with Box–Behnken to Optimize the Medium of Fermented Tremella Polysaccharide and Compare the Characteristics before and after Optimization

The purpose of this study was to improve the yield of fermented Tremella polysaccharide (FTP) by optimizing the medium and to explore the effect of optimization on the structure. In this paper, the Plackett–Burman design and response surface method were used to optimize the fermentation medium of Tremella spore GT2# for FTP production. The results of the Plackett–Burman design showed that potato extract, glucose, and peptone were the main factors. The Box–Behnken experiment and regression analysis determined that the optimal concentrations of potato extract, glucose, and peptone were 22.01%, 29.38 g/L, and 2.61 g/L, respectively. After optimization, the fermentation period shortened from 5 days to 3 days, and the yield of FTP increased from 10.75 g/L to 12.50 g/L, which was in good agreement with the predicted value (12.36 g/L). Characterization of FTP obtained before and after optimization was carried out, and the results showed that medium optimization had significant effects on the primary structure of FTP, including molecular weight, monosaccharide composition, and proportion. After optimization, the content of acid polysaccharide increased, and the glycoside bonds changed from a-configuration to ß-configuration.

Differences in the Moisture Capacity and Thermal Stability of Tremella fuciformis Polysaccharides Obtained by Various Drying Processes

We compared the proportions and differences in the polysaccharides of Tremella fuciformis (Berkeley) after drying them by various processes, such as 18 °C cold air, 50 °C hot air, and freeze-drying. We also focused on the moisture capacity kinetic parameters of Tremella fuciformis polysaccharides using various thermal analyses, including differential scanning calorimetry and thermogravimetric techniques. Erofeev's kinetic and proto-kinetic equations, utilized for kinetic model simulation, can predict the moisture capacity due to the thermal effect. Among the various drying processes, cold air-drying had the highest molecular weight of 2.41 × 10⁷ Da and a moisture content of 13.05% for Tremella fuciformis polysaccharides. Overall, the freeze-dried products had the best thermal decomposition properties under the conditions of a closed system, with an air or nitrogen atmosphere, and had an excellent moisture capacity of around 35 kJ/kg under a closed system for all samples.

Tremella polysaccharide: The molecular mechanisms of its drug action

Tremella fuciformis is an edible medicinal mushroom well known as "Yiner" or "Baimuer" in China and has been used as a Chinese herb for many years. T. fuciformis polysaccharide (TFPS) has been identified as a major bioactive component. Different experimental conditions can obtain different TFPS fractions, which makes TFPS a mixture of different polysaccharides with the molecular weight ranging from 5.82×10⁵Da to 3.74×10⁶Da. The monosaccharides detected in TFPS include mannose, xylose, fucose, glucuronic acid, glucose, and galactose. One characterized TFPS chemical structure consists of a linear (1→3)-linked α-d-mannose backbone with highly branched β-d-xylose, α-d-fucose and β-d-glucuronic acid as the side chains. TFPS shows multiple physiological and healthy promoting effects including immunomodulation, antitumor, anti-oxidation, anti-aging, hypoglycemic, hypolipidemic, neuroprotection, and other effects. As a result, "Tremella Polysaccharide Enteric-coated Capsules" was approved by Chinese Food and Drug Administration (SFDA) in 2002 for treating cancer patients with leukopenia induced by chemotherapy and radiotherapy. It is also used as adjuvant drug for treating chronic persistent hepatitis and chronic active hepatitis. In this chapter, 113 independent studies involving in biochemical, pharmacological, and clinical studies of TFPS during the past 46 years (1972-2018) on the base of PubMed, CNKI (China National Knowledge Infrastructure) and Wanfang database search are summarized. TFPS shows efficacy for all types of human diseases in the reported clinical studies. The structure, molecular mechanisms of the immunomodulation, antitumor, anti-oxidation, anti-aging, hypoglycemic, hypolipidemic, preclinical and clinical efficacy are discussed to provide a general picture of TFPS as a clinically used drug.

An overview of fungal glycan-based therapeutics

Edible medicinal mushrooms have been traditionally used for health promotion and longevity in China and other East Asian countries for centuries. Structural and pharmacological studies revealed that fungal glycans show multiple physiological and healthy promoting effects including immunomodulation, anti-tumor, anti-aging, anti-oxidation, hypoglycemic, hypolipidemic, anti-radiation, and other effects. Fungal glycans isolated from different kinds of medicinal mushrooms are partially purified and clinically tested. Without serious safety concerns of mostly glycans from edible mushrooms and/or the cultured mycelium, eight of them are approved by Chinese Food and Drug Administration (SFDA) and used clinically in China since 1980s. In this chapter, 185 independent studies involving in biochemical, pharmacological and clinical studies of fungal glycans during the past four decades (1977-2019) from PubMed, CNKI (China National Knowledge Infrastructure) and Wanfang databases are summarized. In future, understanding the fungal glycan-based drugs at molecular biological level would be needed to comprehend the clinical efficacy of glycan-based drugs.

Immunomodulatory Effect of Tremella Polysaccharides against Cyclophosphamide-Induced Immunosuppression in Mice

Polysaccharides are closely associated with immune regulation, but there are different polysaccharide effects from different sources. In this study, the aim was to investigate the effect of tremella polysaccharides (TP) in cyclophosphamide-induced immunodeficient mice. We observed the thymus and spleen index, liver and spleen pathological changes, and the levels of IL-2, IL-12, INF-γ, TGF-β and Ig G in serum, and we also noted the mRNA expression of IL-1β, IL-4, IL-12 and TGF-β in liver and spleen. Besides, we also measured the best effects of different doses of TP (Low-TP was 20 mg/kg·BW, Middle-TP was 40 mg/kg·BW, and High-TP was 80 mg/kg·BW) on cyclophosphamide-induced immunosuppressed mice. The results were remarkable, and suggested that TP had a significant effect for enhancing immunity in cyclophosphamide-induced immunosuppression, and the immune enhancement of High-TP had the best results in TP-treated mice. It could significantly increase the thymus and spleen index, alleviate pathological features of immunosuppression such as the arrangement of liver sinusoid and hepatic plates was disordered, massive inflammatory cells infiltrated and fatty degeneration of hepatocytes in liver, and red pulp and white pulp were intermixed, splenic corpuscles demolished and disappeared, splenic sinusoid extended, and lymphocytes of spleen were reduced in spleen. Besides, it could also up-regulate serum levels of IL-2, IL-12, INF-γ and Ig G, reduce the level of TGF-β in serum, markedly promote mRNA expression of IL-1β, IL-4 and IL-12 in liver and spleen, and suppress mRNA expression of TGF-β. Above all, TP showed preventive effect for cyclophosphamide-induced immunosuppressed mice.

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

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

Effects of Blood Purification on Serum Levels of Inflammatory Cytokines and Cardiac Function in a Rat Model of Sepsis

OBJECTIVE

The study aimed to explore the effects of blood purification (BP) on serum levels of inflammatory cytokines and cardiac function in a rat model of sepsis.

METHODS

A rat model of sepsis was established by cecal ligation and puncture. All rats were divided into the normal control, sham operation, model, sham treatment, and BP treatment groups. Cardiac functions, inflammatory cytokines, myocardial enzymes, pathological score of cardiac muscle tissue, and myocardial apoptosis of rats in each group were compared.

RESULTS

Sepsis rats had higher serum levels of inflammatory cytokines and lower cardiac function than those in the normal control and sham operation groups. Compared with the model and sham treatment groups, improved cardiac functions, decreased inflammatory cytokines, myocardial enzymes, pathological score, and myocardial apoptosis and mortality were observed in the BP treatment group.

CONCLUSION

BP may reduce serum levels of inflammatory cytokines and improve cardiac function of sepsis rats.

Fish oil-supplemented parenteral nutrition could alleviate acute lung injury, modulate immunity, and reduce inflammation in rats with abdominal sepsis

The objectives were to confirm that intravenous fish oil (FO) emulsions could alleviate acute lung injury, modulate immunity, and reduce inflammation in rats with abdominal sepsis and to explore the mechanisms of these effects. Thirty-six adult male Sprague-Dawley rats were divided into 4 groups randomly. Two days after central venous catheterization, rats were subjected to cecal ligation and puncture to produce abdominal sepsis. Rats were assigned to receive normal saline or total parenteral nutrition (TPN) containing standard soybean oil emulsions or FO-supplemented TPN at the onset of sepsis for 5 days. A sham operation and control treatment were performed in control group rats. Acute lung injury scores, peripheral blood lymphocyte subsets, plasma cytokines, and Foxp3 expression in the spleen were determined. Compared with the normal saline and TPN without FO, FO-supplemented TPN beneficially altered the distributions of the T-lymphocyte subsets and downregulated the acute lung injury scores, plasma cytokines, and expression of Foxp3 due to sepsis. Fish oil-supplemented TPN can decrease acute lung injury scores, alleviate histopathology, reduce the bacterial load in the peritoneal lavage fluid, modulate the lymphocyte subpopulation in the peripheral blood, downregulate Foxp3 expression in the spleen, and reduce plasma cytokines, which means that FO-supplemented TPN can alleviate acute lung injury, modulate immunity, and reduce inflammation in rats with abdominal sepsis.