Chitosan oligosaccharides in combination with Agaricus blazei Murill extract reduces hepatoma formation in mice with severe combined immunodeficiency

The preparation, modification and hepatoprotective activity of chitooligosaccharides: A review

Chitooligosaccharides (COS) has attracted increasing attention due to the various promising bioactivities, tremendous potential in agricultural, environmental nutritional and functional food fields. COS as the major degradation product from chitosan or chitin is prepared via enzymatic, chemical and physical methods. Further obtained COS generally possesses different structural characteristics, such as molecular weight, degree of acetylation and degree of polymerization. Innovations into COS modification has also broadened application of COS in nutrition as well as in agricultural safety. Due to the affinity between structure and bioactivity, diversity of structural characteristics endows COS with various bioactivities like antitumor, antioxidant and anti-inflammatory effects, especially hepatoprotective activity. Therefore, the present review narrates the recent developments in COS physicochemical properties, while paying considerable attention to preparation strategies of COS and their advantages and disadvantages. Moreover, the modification of COS is also discussed including alkylation, quaternization and sulfation, herein the structure-activity relationship of COS was highlighted. Additionally, we summarize the latest research on hepatoprotective activity and mechanisms of COS. Eventually, the future directions of research on COS were discussed, which would provide a new appreciation for the future use of COS.

Agaricus blazei Murrill Polysaccharide Attenuates Periodontitis via H2 S/NRF2 Axis-Boosted Appropriate Level of Autophagy in PDLCs

SCOPE

Periodontitis is one of the most prevalent chronic inflammatory diseases with impaired autophagy. Agaricus blazei Murrill polysaccharide (ABMP) shows beneficial effects in various inflammatory diseases. However, whether ABMP is involved in autophagy regulation and periodontitis attenuation remains to be elucidated.

METHODS AND RESULTS

This study firstly shows the dynamic changes in inflammatory and autophagy levels in silk ligature periodontitis model. Then the positive regulation effect of autophagy on inflammation and its vital role in ABMP inhibiting PDLCs inflammatory response are testified in LPS-treated PDLCs. Secondly, the Micro-CT, quantitative RT-PCR, Western Blot, TRAP, and immunofluorescence staining analysis are performed to assess the effects of ABMP on periodontitis and autophagy. The data show the augmented autophagy and alleviated gingival recession, inflammatory cell infiltration, alveolar bone resorption, and reduced osteoclasts in periodontitis by ABMP treatment. Further experiments using chemical inhibitors demonstrate the vital role of H2 S/NRF2 axis in ABMP-induced appropriate level of autophagy augmentation against periodontitis.

CONCLUSIONS

Collectively, the findings not only reveal the unrecognized capacity and mechanism of ABMP as an effective and potential dietary intake against periodontitis, but also suggest the possibility for ABMP to be used in the treatment of other autophagy-related diseases.

Isolation and Identification of Chemical Compounds from Agaricus blazei Murrill and Their In Vitro Antifungal Activities

This study explores the antifungal properties of Agaricus blazei Murrill, a valuable medicinal and edible fungus. Six compounds (1-6) were first isolated from A. blazei using various isolation techniques and identified using spectroscopic methods. These compounds include linoleic acid, 1,1'-oxybis(2,4-di-tert-butylbenzene), glycerol monolinoleate, volemolide (17R)-17-methylincisterol, (24s)-ergosta-7-en-3-ol, and dibutyl phthalate. This study also assesses the antifungal activities of these compounds against Trichophyton mentagrophology, Trichophyton rubrum, Candida albicans, and Cryptococcus neoformans. The results demonstrate varied sensitivities against these pathogenic fungi, with compound 2 showing significant inhibition against T. mentagrophology, compound 3 showing significant inhibition against T. rubrum, and compound 6 showing significant inhibition against C. albicans. This study underscores the medicinal potential of A. blazei as an antifungal agent and sheds light on its valuable research implications.

Aggravated hepatic fibrosis induced by phenylalanine and tyrosine was ameliorated by chitooligosaccharides supplementation

Hepatic fibrosis is a classic pathological manifestation of metabolic chronic hepatopathy. The pathological process might either gradually deteriorate into cirrhosis and ultimately liver cancer with inappropriate nutrition supply, or be slowed down by several multifunctional nutrients, alternatively. Herein, we found diet with excessive phenylalanine (Phe) and tyrosine (Tyr) exacerbated hepatic fibrosis symptoms of liver dysfunction and gut microflora dysbiosis in mice. Chitooligosaccharides (COS) could ameliorate hepatic fibrosis with the regulation of amino acid metabolism by downregulating the mTORC1 pathway, especially that of Phe and Tyr, and also with the alleviation of the dysbiosis of gut microbiota, simultaneously. Conclusively, this work presents new insight into the role of Phe and Tyr in the pathologic process of hepatic fibrosis, while revealing the effectiveness and molecular mechanism of COS in improving hepatic fibrosis from the perspective of metabolites.

Effect of Agaricus blazei Murill on exploratory behavior of mice-model

Increased anxiety and depressive symptoms have reported to be its association with long term illness. Because of having unwanted effects of newly available drugs, patients administering anxiolytic drugs usually discontinue the treatment before they are completely recovered. Therefore, there is a serious need to develop new anxiolytic drugs. The anxiolytic effect of hydro-alcoholic extract of Agaricus blazei in animal models was assessed. 24 male mice (Mus musculus genus) were included in the study. Four groups were prepared and each group contained six animals. The groups were vehicle control, positive control (diazepam 1.0 mg/kg, i.p.) as well as two treatment groups receiving Agaricus blazei hydro-alcoholic extract at a dose of 136.50 mg/kg and 273.0 mg/kg orally. The Marble burying test, Nestlet shredding test and Light and Dark box test used to assess anxiolytic activity. Mice administered with diazepam 1.0 mg/kg, i.p. while hydro-alcoholic extract of AbM (136.50 and 273.0 mg/kg, respectively) was administered via oral route which exhibited marked reduction in number of marbles-burying as compared to vehicle control group. Mice administered with diazepam 1.0 mg/kg, i.p. and Oral administration of hydro-alcoholic extract of AbM (136.50 and 273.0 mg/kg, respectively) exhibited significant decrease in nestlet shredding in comparison to vehicle control group. The oral administration of hydro-alcoholic extract at a dose of 136.5mg/kg and 273mg/kg showed elevation in time spent in light box and was comparable to standard treated group while time spent by mice following oral administration of hydro-alcoholic extract of Agaricus blazei at a dose of 273.0 mg/kg also showed elevation and was found to be more near to standard treated group (diazepam 1 mg/kg, i.p.).

Treasures from the forest: Evaluation of mushroom extracts as anti-cancer agents

Mushrooms provide a reliable source of bioactive compounds and have numerous nutritional values, which is one of the reasons why they are widely used for culinary purposes. They may also be a remedy for several medical conditions, including cancer diseases. Given the constantly increasing number of cancer incidents, the great anticancer potential of mushrooms has unsurprisingly become an object of interest to researchers. Therefore, this review aimed to collect and summarize all the available scientific data on the anti-cancer activity of mushroom extracts. Our research showed that mushroom extracts from 92 species, prepared using 12 different solvents, could reduce the viability of 38 various cancers. Additionally, we evaluated different experimental models: in vitro (cell model), in vivo (mice and rat model, case studies and randomized controlled trials), and in silico. Breast cancer proved to be sensitive to the highest number of mushroom extracts. The curative mechanisms of the studied mushrooms consisted in: inhibition of cancer cell proliferation, unregulated proportion of cells in cell cycle phases, induction of autophagy and phagocytosis, improved response of the immune system, and induction of apoptotic death of cells via upregulation of pro-apoptotic factors and downregulation of anti-apoptotic genes. The processes mainly involved the expression of caspases -3, -8, -9, AKT, p27, p53, BAX, and BCL2. The quoted results could lead to the classification of mushrooms as nutraceuticals used to prevent a variety of disorders or to support treatment of cancer diseases.

Antitumor, Anti-Inflammatory and Antiallergic Effects of Agaricus blazei Mushroom Extract and the Related Medicinal Basidiomycetes Mushrooms, Hericium erinaceus and Grifola frondosa: A Review of Preclinical and Clinical Studies

Since the 1980s, medicinal effects have been documented in scientific studies with the related Basidiomycota mushrooms Agaricus blazei Murill (AbM), Hericium erinaceus (HE) and Grifola frondosa (GF) from Brazilian and Eastern traditional medicine. Special focus has been on their antitumor effects, but the mushrooms' anti-inflammatory and antiallergic properties have also been investigated. The antitumor mechanisms were either direct tumor attack, e.g., apoptosis and metastatic suppression, or indirect defense, e.g., inhibited tumor neovascularization and T helper cell (Th) 1 immune response. The anti-inflammatory mechanisms were a reduction in proinflammatory cytokines, oxidative stress and changed gut microbiota, and the antiallergic mechanism was amelioration of a skewed Th1/Th2 balance. Since a predominant Th2 milieu is also found in cancer, which quite often is caused by a local chronic inflammation, the three conditions-tumor, inflammation and allergy-seem to be linked. Further mechanisms for HE were increased nerve and beneficial gut microbiota growth, and oxidative stress regulation. The medicinal mushrooms AbM, HE and GF appear to be safe, and can, in fact, increase longevity in animal models, possibly due to reduced tumorigenesis and oxidation. This article reviews preclinical and clinical findings with these mushrooms and the mechanisms behind them.

Expression and characterization of a chitinase from Serratia marcescens

A chitinase gene from Serratia marcescens was cloned and expressed in Escherichia coli BL21(DE3) and the properties of recombinant chitinase rCHI-2 were characterized. The optimum catalytic pH of rCHI-2 was 6.0. It was stable in the pH range of 6.0-9.0 and could maintain more than 90% of its relative enzyme activity after incubation at 37 °C for 1 h. The optimum catalytic temperature of the enzyme was 55 °C and 85% of enzyme activity was remained after incubation at 45 °C for 1 h. The activation energy of the thermal inactivation of the enzyme was 10.9 kJ/mol and the Michaelis-Menten constant was 3.2 g/L. The purified rCHI-2 was found to be highly stable at 45 °C with half-life (t_1/2) of 289 min and thermodynamic parameters ΔH*, ΔG* and ΔS* revealed high affinity of rCHI-2 for chitin. Hg²⁺ was found to be able to inhibit the enzyme activity reversibly, while IC50 and inhibition constant of Hg²⁺ on the enzyme were 34.8 μmol/L and 44.6 μmol/L, respectively. Moreover, rCHI-2 could specifically hydrolyze colloidal chitin into GlcNAc₂ as the major product.