Identification of Inonotus obliquus polysaccharide with broad-spectrum antiviral activity against multi-feline viruses

The function and application of edible fungal polysaccharides

Edible fungi, commonly known as mushrooms, are precious medicinal and edible homologous gifts from nature to us. Edible fungal polysaccharides (EFPs) are a variety of bioactive macromolecular which isolated from fruiting bodies, mycelia or fermentation broths of edible or medicinal fungus. Increasing researches have confirmed that EFPs possess multiple biological activities both in vitro and in vivo settings, including antioxidant, antiviral, anti-inflammatory, immunomodulatory, anti-tumor, hypoglycemic, hypolipidemic, and regulating intestinal flora activities. As a result, they have emerged as a prominent focus in the healthcare, pharmaceutical, and cosmetic industries. Fungal EFPs have safe, non-toxic, biodegradable, and biocompatible properties with low immunogenicity, bioadhesion ability, and antibacterial activities, presenting diverse potential applications in the food industries, cosmetic, biomedical, packaging, and new materials. Moreover, varying raw materials, extraction, purification, chemical modification methods, and culture conditions can result in variances in the structure and biological activities of EFPs. The purpose of this review is to provide comprehensively and systematically organized information on the structure, modification, biological activities, and potential applications of EFPs to support their therapeutic effects and health functions. This review provides new insights and a theoretical basis for prospective investigations and advancements in EFPs in fields such as medicine, food, and new materials.

Evaluation of the Polysaccharide "Immeran" Activity in Syrian hamsters' Model of SARS-CoV-2

COVID-19 is a highly contagious respiratory disease with a high number of lethal cases in humans, which causes the need to search for new therapeutic agents. Polysaccharides could be one of the prospective types of molecules with a large variety of biological activities, especially antiviral. The aim of this work was to study the specific antiviral activity of the drug "Immeran" on a model of a new coronavirus infection SARS-CoV-2 in hamsters. Based on the second experiment, intraperitoneal treatment with the drug according to a treatment regimen in doses of 500 and 1000 μg/kg (administration after an hour, then once a day every other day, a total of 3 administrations) was effective, reliably suppressing the replication of the virus in the lungs and, at a dose of 1000 μg/kg, prevented weight loss in animals. In all cases, the treatment stimulated the formation of virus-neutralizing antibodies to the SARS-CoV-2 virus, which suggests that the drug possesses adjuvant properties.

In silico targeting of SARS-CoV-2 spike receptor-binding domain from different variants with chaga mushroom terpenoids

Terpenoids from the chaga mushroom have been identified as potential antiviral agents against SARS-CoV-2. This is because it can firmly bind to the viral spike receptor binding domain (RBD) and the auxiliary host cell receptor glucose-regulated protein 78 (GRP78). The current work examines the association of the chaga mushroom terpenoids with the RBD of various SARS-CoV-2 variants, including alpha, beta, gamma, delta, and omicron. This association was compared to the SARS-CoV-2 wild-type (WT) RBD using molecular docking analysis and molecular dynamics modeling. The outcomes demonstrated that the mutant RBDs, which had marginally greater average binding affinities (better binding) than the WT, were successfully inhibited by the chaga mushroom terpenoids. The results suggest that the chaga mushroom can be effective against various SARS-CoV-2 variants by targeting both the host-cell surface receptor GRP78 and the viral spike RBD.Communicated by Ramaswamy H. Sarma.

Chaga mushroom: a super-fungus with countless facets and untapped potential

Inonotus obliquus (Chaga mushroom) is an inexpensive fungus with a broad range of traditional and medicinal applications. These applications include therapy for breast, cervix, and skin cancers, as well as treating diabetes. However, its benefits are virtually untapped due to a limited understanding of its mycochemical composition and bioactivities. In this article, we explore the ethnobotany, mycochemistry, pharmacology, traditional therapeutic, cosmetic, and prospective agricultural uses. The review establishes that several secondary metabolites, such as steroids, terpenoids, and other compounds exist in chaga. Findings on its bioactivity have demonstrated its ability as an antioxidant, anti-inflammatory, antiviral, and antitumor agent. The study also demonstrates that Chaga powder has a long history of traditional use for medicinal purposes, pipe smoking rituals, and mystical future forecasts. The study further reveals that the applications of Chaga powder can be extended to industries such as pharmaceuticals, food, cosmetics, and agriculture. However numerous publications focused on the pharmaceutical benefits of Chaga with few publications on other applications. Overall, chaga is a promising natural resource with a wide range of potential applications and therefore the diverse array of therapeutic compounds makes it an attractive candidate for various applications such as plant biofertilizers and active ingredients in cosmetics and pharmaceutical products. Thus, further exploration of Chaga's potential benefits in agriculture and other industries could lead to exciting new developments and innovations.

Biopharmaceutical applications of microbial polysaccharides as materials: A review

Biological characteristics of natural polymers make microbial polysaccharides an excellent choice for biopharmaceuticals. Due to its easy purifying procedure and high production efficiency, it is capable of resolving the existing application issues associated with some plant and animal polysaccharides. Furthermore, microbial polysaccharides are recognized as prospective substitutes for these polysaccharides based on the search for eco-friendly chemicals. In this review, the microstructure and properties of microbial polysaccharides are utilized to highlight their characteristics and potential medical applications. From the standpoint of pathogenic processes, in-depth explanations are provided on the effects of microbial polysaccharides as active ingredients in the treatment of human diseases, anti-aging, and drug delivery. In addition, the scholarly developments and commercial applications of microbial polysaccharides as medical raw materials are also discussed. The conclusion is that understanding the use of microbial polysaccharides in biopharmaceuticals is essential for the future development of pharmacology and therapeutic medicine.

New Inonotus Polysaccharides: Characterization and Anticomplementary Activity of Inonotus rheades Mycelium Polymers

Inonotus is a small genus of xylotrophic basidiomycetes and a source of bioactive fungochemicals among which a special place is occupied by polymeric compounds. In this study, polysaccharides that are widespread in Europe, Asia, and North America and a poorly understood fungal species, I. rheades (Pers.) Karst. (fox polypore), were investigated. Water-soluble polysaccharides of I. rheades mycelium were extracted, purified, and studied using chemical reactions, elemental and monosaccharide analysis, UV-Vis and FTIR spectroscopy, gel permeation chromatography, and linkage analysis. Five homogenic polymers (IRP-1-IRP-5) with molecular weights of 110-1520 kDa were heteropolysaccharides that consist mainly of galactose, glucose, and mannose. The dominant component, IRP-4, was preliminary concluded to be a branched (1→3,6)-linked galactan. Polysaccharides of I. rheades inhibited the hemolysis of sensitized sheep erythrocytes by complement from human serum, signifying anticomplementary activity with the greatest effects for the IRP-4 polymer. These findings suggest that I. rheades mycelium is a new source of fungal polysaccharides with potential immunomodulatory and anti-inflammatory properties.

Polysaccharide derived from Inonotus obliquus inhibits lipopolysaccharide-induced acute endometritis in mice

OBJECTIVE

Endometritis bacterial pathogenic condition that affects both humans and animals develops in the inner lining of the uterus. Inonotus obliquus polysaccharide (IOP), an active cocktail of Inonotus obliquus, has been shown to have a relatively wide range of biological activities and can play a role in various diseases. However, from the currently reported article, there is no information about the anti-inflammatory effect of IPO in the symptoms of lipopolysaccharide (LPS)-induced endometritis. Therefore, this study carefully observed the phenomenon of IOP on the symptoms of endometritis induced by LPS in mice, elucidated the protective mechanism of IOP on the body, and clarified the potential mechanism of IOP.

METHODS

A total of 72 BALB/c female experimental mice were divided into several groups for comparison. They were the blank control group, the LPS group, the LPS+ IOP group (the effect of IOP dose on mice was also explored, divided into low, medium, and high) and LPS+ amoxicillin group. All groups except control group were infused with LPS into the uterus. The mice of LPS+ IOP groups and LPS+ amoxicillin group were orally administered with IOP or amoxicillin after LPS challenge for 3 hours. Histopathology and myeloperoxidase (MPO) activity were used to detect uterine tissue injury, and cytokine levels were used to measure uterine inflammation. The expression of toll-like receptor 4/nuclear factor-kappa B (TLR4/NF-κB)-related proteins in the inflammatory signaling pathway was observed.

RESULTS

Pathological and MPO activity analyses revealed that IOP relieved LPS-induced uterine tissue injury. Quantitative reverse transcription-polymerase chain reaction was used to detect and quantitatively study the RNA information of mouse cells, which had high accuracy and sensitivity. From the test results, IOP does effectively control the release of pro-inflammatory cytokines such as interleukin-6 (IL-6), IL-1β, IL-8 and tumor necrosis factor-α (TNF-α), avoiding the body's immune response. Analysis of uterine tissue cell components also confirmed that the expression level of inflammatory mediator-induced nitric oxide synthase (iNOS) was also greatly reduced. Analysis of western blotting results of cell synthesis showed that IOP mainly inhibited the protein expression of TLR4 and myeloid differentiation factor 88 in the body.

CONCLUSION

This study proved that the mechanism of action of IOP is to inhibit the TLR4/NF-κB signaling pathway to reduce the release of pro-inflammatory cytokines from body cells, thereby alleviating the symptoms of endometritis induced by LPS. Thus, IOP may act as an effective drug in preventing and curing LPS-induced endometritis.

A concise review of mushrooms antiviral and immunomodulatory properties that may combat against COVID-19

The World Health Organization (WHO) declared COVID-19 as a pandemic on March 11, 2020, because of its widespread transmission and infection rates. The unique severe disease was found in Wuhan, China, since December 2019, and swiftly spread throughout the world. Natural chemicals derived from herbal medicines and medicinal mushrooms provide a significant resource for the development of novel antiviral drugs. Many natural drugs have been proven to have antiviral properties against a variety of virus strains, such as the coronavirus and the herpes simplex virus (HSV).. In this research, successful dietary treatments for different COVID illnesses were compared to potential of mushroom products in its therapy. In Google Scholar, Science Direct, PubMed, and Scopus, search keywords like COVID, COVID-19, SARS, MERS, mushrooms, and their compounds were utilized. In this review of the literature we foucsed popular mushrooms such as Agaricus subrufescens Peck, Agaricus blazei Murill, Cordyceps sinensis (Berk.) Sacc., Ganoderma lucidum (Curtis.) P. Karst., Grifola frondosa (Dicks.) Gray, Hericium erinaceus (Bull.) Pers., Inonotus obliquus (Arch. Ex Pers.) Pilát., Lentinula edodes (Berk.) Pegler, Pleurotus ostreatus (Jacq.) P. Kumm., Poria cocos F.A. Wolf, and Trametes versicolor (L.) Lloyd.,. Changed forms of β-Glucan seem to have a good impact on viral replication suppression and might be used in future studies. However, the results seems terpenoids, lectins, glycoproteins, lentinan, galactomannan, and polysaccharides from mushrooms are promising prophylactic or therapeutic agents against COVID-19.

The Mechanisms of Lipid Vesicle Fusion Inhibition by Extracts of Chaga and Buckthorn Leaves

The ability of extracts of grapefruit seeds (ESG), sea buckthorn leaves (ESBL), and chaga (EC) to inhibit membrane fusion was evaluated. It was found that ESBL and EC inhibited Ca²⁺-mediated fusion of phosphatidylglycerol-enriched lipid vesicles; the inhibition indexes were about 90 and 100%, respectively. ESG did not inhibit the fusion of negatively charged liposomes induced by calcium. In addition to calcium-mediated liposome fusion, EC inhibited the fusion of vesicles from a mixture of phosphatidylcholine and cholesterol under the action of polyethylene glycol with a molecular weight of 8000 Da (the inhibition index was 80%). The other two extracts had no effect on polymer-induced fusion of uncharged membranes. The effect of some major components of the tested extracts on the fusion of vesicles was evaluated. It has been shown that flavonols, quercetin and myricetin, which are major components of ESBL, inhibited the fusion of negatively charged membranes under the action of calcium (the inhibition indexes were about 85 and 60%, respectively). Another flavonol of ESBL, the glycoside of quercetin rutin, did not have such an effect. The data obtained made it possible to relate the ESBL suppression of calcium-induced fusion of lipid vesicles with the presence of quercetin and myricetin in its composition. These flavonols had virtually no effect on polyethylene glycol-induced vesicle fusion, which is consistent with the absence of ESBL action on liposome fusion under the action of polymer. The ability of quercetin and myricetin to reduce the melting temperature of phosphatidylglycerol with saturated hydrocarbon chains and to increase the half-width of the peak corresponding to melting has been demonstrated. The observed correlation between the parameters characterizing the thermotropic behavior of the lipid in the presence of quercetin and myricetin and the index of inhibition of calcium-mediated liposome fusion by these compounds may indicate a relationship between the ability of flavonols to influence the packaging of membrane lipids and inhibit vesicle fusion. Pentacyclic triterpenoids, betulin and lupeol, which are part of EC, did not inhibit the fusion of vesicles under the action of both calcium and polyethylene glycol, and their presence in EC cannot be responsible for the antifusogenic activity of EC.

Targeting SARS-CoV-2 with Chaga mushroom: An in silico study toward developing a natural antiviral compound

The novel coronavirus (SARS-CoV-2) has caused large-scale global outbreaks and mainly mediates host cell entry through the interaction of its spike (S) protein with the human angiotensin-converting enzyme-2 (ACE-2) receptor. As there is no effective treatment for SARS-CoV-2 to date, it is imperative to explore the efficacy of new compounds that possess potential antiviral activity. In this study, we assessed the potential binding interaction of the beneficial components of Chaga mushroom, a natural anti-inflammatory and immune booster with that of the SARS-CoV-2 receptor-binding domain (RBD) using molecular docking, MD simulation, and phylogenetic analysis. Beta glycan, betulinic acid, and galactomannan constituents of Chaga mushroom exhibited strong binding interaction (-7.4 to -8.6 kcal/mol) forming multivalent hydrogen and non-polar bonds with the viral S1-carboxy-terminal domain of the RBD. Specifically, the best interacting sites for beta glycan comprised ASN-440, SER 373, TRP-436, ASN-343, and ARG 509 with average binding energy of -8.4 kcal/mol. The best interacting sites of galactomannan included ASN-437, SER 373, TRP-436, ASN-343, and ALA 344 with a mean binding energy of -7.4 kcal/mol; and the best interacting sites of betulinic acid were ASN-437, SER 373, TRP-436, PHE 342, ARG 509, and ALA 344 that strongly interacted with the S-protein (ΔG = -8.1 kcal/mol). The docking results were also compared with an S-protein binding analog, NAG and depicted similar binding affinities compared with that of the ligands (-8.67 kcal/mol). In addition, phylogenetic analysis using global isolates depicted that the current SARS-CoV-2 isolates possessed a furin cleavage site (NSPRRA) in the RBD, which was absent in the previous isolates that indicated increased efficacy of the present virus for enhanced infection through increased interaction with ACE-2. The results showed that Chaga could be an effective natural antiviral that can supplement the current anti-SARS-CoV-2 drugs.

Effect of Inonotus obliquus polysaccharide on composition of the intestinal flora in mice with acute endometritis

Inonotus obliquus Polysaccharide (IOP) is a large molecule extracted from Inonotus obliqus, a medicinal fungus, which has a wide range of biological activities and has been shown to be associated with inflammation. The purpose of this study is to investigate whether IOP can help to reduce acute endometritis by regulating intestinal flora. We observed pathological changes in mice with endometritis following treatment with IOP and evaluated changes in the levels of interleukin-6 (IL-6), interleukin-1β (IL-1β) and tumor necrosis factor α (TNF-α), and further studied the effects of IOP on the intestinal flora of endometritis mice using 16S rRNA high-throughput sequencing. The results showed that IOP improved the condition of uterine tissues and reduced the release of pro-inflammatory cytokines. Meanwhile, the 16S rRNA sequencing results showed that IOP could regulate the changes in intestinal microflora at the level of genera, possibly by changing the relative abundance of some genera.

The Antiviral Activity of Bacterial, Fungal, and Algal Polysaccharides as Bioactive Ingredients: Potential Uses for Enhancing Immune Systems and Preventing Viruses

Viral infections may cause serious human diseases. For instance, the recent appearance of the novel virus, SARS-CoV-2, causing COVID-19, has spread globally and is a serious public health concern. The consumption of healthy, proper, functional, and nutrient-rich foods has an important role in enhancing an individual's immune system and preventing viral infections. Several polysaccharides from natural sources such as algae, bacteria, and fungi have been considered as generally recognized as safe (GRAS) by the US Food and Drug Administration. They are safe, low-toxicity, biodegradable, and have biological activities. In this review, the bioactive polysaccharides derived from various microorganisms, including bacteria, fungi, and algae were evaluated. Antiviral mechanisms of these polysaccharides were discussed. Finally, the potential use of microbial and algal polysaccharides as an antiviral and immune boosting strategy was addressed. The microbial polysaccharides exhibited several bioactivities, including antioxidant, anti-inflammatory, antimicrobial, antitumor, and immunomodulatory activities. Some microbes are able to produce sulfated polysaccharides, which are well-known to exert a board spectrum of biological activities, especially antiviral properties. Microbial polysaccharide can inhibit various viruses using different mechanisms. Furthermore, these microbial polysaccharides are also able to modulate immune responses to prevent and/or inhibit virus infections. There are many molecular factors influencing their bioactivities, e.g., functional groups, conformations, compositions, and molecular weight. At this stage of development, microbial polysaccharides will be used as adjuvants, nutrient supplements, and for drug delivery to prevent several virus infections, especially SARS-CoV-2 infection.

Triterpenoid acids from medicinal mushroom Inonotus obliquus (Chaga) alleviate hyperuricemia and inflammation in hyperuricemic mice: Possible inhibitory effects on xanthine oxidase activity

The purpose of this study was to explore the hypouricemic effect in hyperuricemia mice of triterpenoid acids from Inonotus obliquus (TAIO), and decipher of the underlying xanthine oxidase inhibitory mechanism. Measurement of xanthine oxidase (XO) inhibitory activity was assayed. Organ indexes and serum biochemical indicators were measured in potassium oxonate-induced hyperuricemia mice. Studies showed that TAIO had the strong inhibitory effect on XO activity, and its inhibition type was mixed and reversible. In vivo, TAIO decreased efficiently uric acid level, hepatic XO, serum blood urea nitrogen activities in hyperuricemia mice. Indicating that TAIO may ameliorate kidney damage and relieve inflammation in hyperuricemic mice, and had the inhibitory effect on XO activity. Furthermore, eight triterpenoids were identified by Ultra performance liquid chromatography electrospray quadrupole time of flight mass spectrometry. These findings proved that triterpenoids from Inonotus obliquus would have potential biological characteristics and effect on controlling hyperuricemia and gout as an active supplement. PRACTICAL APPLICATIONS: There are a large amount of evidence indicating that hyperuricemia and gout are related to the hypertension and obesity. And gout and hyperuricemia are also possible connection with cardiovascular disease and metabolic syndrome. Currently, xanthine oxidase is the target of many kinds of chemical drugs at present, but the therapeutic drugs used in clinical medicine will produce more or less side effects. Therefore, the aim of this study was to explore the material basis of effective substances for reducing uric acid in Inonotus obliquus and to evaluate its effect. This study can provide a promising application of Inonotus obliquus in the fields of functional foods or medicines for gout and hyperuricemia.

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.

Recent Developments in Inonotus obliquus (Chaga mushroom) Polysaccharides: Isolation, Structural Characteristics, Biological Activities and Application

Inonotus obliquus (Chaga mushroom) is a kind of medicine and health food widely used by folk in China, Russia, Korea, and some occidental countries. Among the extracts from Inonotus obliquus, Inonotus obliquus polysaccharide (IOPS) is supposed to be one of the major bioactive components in Inonotus obliquus, which possesses antitumor, antioxidant, anti-virus, hypoglycemic, and hypolipidemic activities. In this review, the current advancements on extraction, purification, structural characteristics, and biological activities of IOPS were summarized. This review can provide significant insight into the IOPS bioactivities as their in vitro and in vivo data were summarized, and some possible mechanisms were listed. Furthermore, applications of IOPS were reviewed and discussed; IOPS might be a potential candidate for the treatment of cancers and type 2 diabetes. Besides, new perspectives for the future work of IOPS were also proposed.

Antiviral Bioactive Compounds of Mushrooms and Their Antiviral Mechanisms: A Review

Mushrooms are used in their natural form as a food supplement and food additive. In addition, several bioactive compounds beneficial for human health have been derived from mushrooms. Among them, polysaccharides, carbohydrate-binding protein, peptides, proteins, enzymes, polyphenols, triterpenes, triterpenoids, and several other compounds exert antiviral activity against DNA and RNA viruses. Their antiviral targets were mostly virus entry, viral genome replication, viral proteins, and cellular proteins and influenced immune modulation, which was evaluated through pre-, simultaneous-, co-, and post-treatment in vitro and in vivo studies. In particular, they treated and relieved the viral diseases caused by herpes simplex virus, influenza virus, and human immunodeficiency virus (HIV). Some mushroom compounds that act against HIV, influenza A virus, and hepatitis C virus showed antiviral effects comparable to those of antiviral drugs. Therefore, bioactive compounds from mushrooms could be candidates for treating viral infections.

Deciphering the antitumoral potential of the bioactive metabolites from medicinal mushroom Inonotus obliquus

ETHNOPHARMACOLOGICAL RELEVANCE

The crude extracts of the medicinal mushroom Inonotus obliquus have been used as an effective traditional medicine to treat malicious tumors, gastritis, gastric ulcers, and other inflammatory conditions in Russia and most Baltic countries.

AIM OF THIS REVIEW

Deciphering the antitumoral potential of the bioactive metabolites from I. obliquus and addressing its possibility to be used as effective agents for tumor treatment, restoration of compromised immunity and protection of gastrointestinal damage caused by chemotherapy.

MATERIALS AND METHODS

We analysed the current achievements and dilemma in tumor chemo- or immunotherapy. In this context, we searched the published literatures on I. obliquus covering from 1990 to 2020, and summarized the activities of antitumor, antioxidation, and immunomodulation by the polysaccharides, triterpenoids, small phenolic compounds, and hispidin polyphenols. By comparing the merits and shortcomings of current and traditional methodology for tumor treatment, we further addressed feasibility for the use of I. obliquus as an effective natural drug for tumor treatment and prevention.

RESULTS

The diverse bioactive metabolites confer I. obliquus great potential to inhibit tumor growth and metastasis. Its antitumor activities are achieved either through suppressing multiple oncogenic signals including but not limited to the activation of NF-κB and FAK, and the expression of RhoA/MMP-9 via ERK1/2 and PI3K/Akt signaling pathway. The antitumor activities can also be achieved by inhibiting tyrosinase activity via PAK1-dependent signaling pathway or altering lysosomal membrane permeabilization through blocking tubulin polymerization and/or disturbing energy metabolism through LKB1/AMPK pathway. In addition, the metabolites from I. obliquus also harbour the potentials to reverse MDR either through selective inhibition on P-gp/ABCB1 or MRP1/ABCC1 proteins or the induction of G2/M checkpoint arrest in tumor cells of chemoresistant phenotypes mediated by Nox/ROS/NF-kB/STAT3 signaling pathway. In addition to the eminent effects in tumor inhibition, the metabolites in I. obliquus also exhibit immunomodulatory potential to restore the compromised immunity and protect against ulcerative damage of GI tract caused by chemotherapy.

CONCLUSIONS

I. obliquus possesses the potential to reduce incidence of tumorigenesis in healthy people. For those whose complete remission has been achieved by chemotherapy, administration of the fungus will inhibit the activation of upstream oncogenic signals and thereby prevent metastasis; for those who are in the process of chemotherapy administration of the fungus will not only chemosensitize the tumor cells and thereby increasing the chemotherapeutic effects, but also help to restore the compromised immunity and protect against ulcerative GI tract damage and other side-effects induced by chemotherapy.

Effects of Pinus massoniana pollen polysaccharides on intestinal microenvironment and colitis in mice

The stability of the intestinal microenvironment is the basis for maintaining the normal physiological activities of the intestine. On the contrary, disordered dynamic processes lead to chronic inflammation and disease pathology. Pinus massoniana pollen polysaccharide (PPPS), isolated from Taishan Pinus massoniana pollen, has been reported with extensive biological activities, including immune regulation. However, the role of PPPS in the intestinal microenvironment and intestinal diseases is still unknown. In this work, we initiated our investigation by using 16S rRNA high-throughput sequencing technology to assess the effect of PPPS on gut microbiota in mice. The result showed that PPPS regulated the composition of gut microbiota in mice and increased the proportion of probiotics. Subsequently, we established immunosuppressive mice using cyclophosphamide (CTX) and found that PPPS regulated the immunosuppressive state of lymphocytes in Peyer's patches (PPs). Moreover, PPPS also regulated systemic immunity by acting on intestinal PPs. PPPS alleviated lipopolysaccharide (LPS) -induced Caco2 cell damage, indicating that PPPS has the ability to reduce the damage and effectively improve the barrier dysfunction in Caco2 cells. In addition, PPPS alleviated colonic injury and relieved colitis symptoms in dextran sodium sulfate (DSS)-induced colitis mice. Overall, our findings indicate that PPPS shows a practical regulatory effect in the intestinal microenvironment, which provides an essential theoretical basis for us to develop the potential application value of PPPS further.

Quality control and evaluation of Inonotus obliquus using HPLC method with novel marker compounds

Current quality control ofInonotus obliquusrequires chromogen complex content limit of 10% in accordance with the State Pharmacopoeia of the Union of Soviet Socialist Republics. However, this causes ambiguous results, impeding precise quality control. To improve ambiguous quality control criteria, this study developed a new HPLC method using two novel marker compounds (inotodiol and 3β-hydroxylanosta-8,24-dien-21-al) to control the quality control ofI. obliquus. The HPLC analysis was carried out in a C18 column with an isocratic elution of 95% acetonitrile at 210 nm. The developed method validated in terms of linearity, precision, accuracy, and recovery. The content criteria were established by the linear regression method and relative standard deviation method. As the results of the quantitative monitoring, 1.165 mg/g of inotodiol and 1.717 mg/g of 3β-hydroxylanosta-8,24-dien-21-al, calculated by the relative standard deviation method, were suggested new quality criteria. A new HPLC method was developed to improve current quality control ofI. obliquusand new lower content criteria were proposed as a result of quantitative monitoring.

Graphical abstract

Antiviral activity against porcine epidemic diarrhea virus of Pogostemon cablin polysaccharide

ETHNOPHARMACOLOGICAL RELEVANCE

The dry overground parts of Pogostemon cablin (Blanco) Benth. is widely used in China as a traditional Chinese medicine for the treatment of diarrhea, vomiting, nausea and fever. Polysaccharide is an important component of Pogostemon cablin (Blanco) Benth. but has not been studied. Pogostemon cablin (Blanco) Benth. is used to treat porcine epidemic diarrhea. But it is not known whether Pogostemon cablin polysaccharides (PCPs) has the antiviral activities against porcine epidemic diarrhea virus (PEDV).

AIM OF THE STUDY

The purpose of present study is to investigate the structural characterization and the anti-PEDV activities of PCPs.

MATERIALS AND METHODS

PCPs were prepared by water extraction and alcohol precipitation method and purified with DEAE-52 cellulose column and Sephadex G-100 column. Then, the structural characterization of the polysaccharides including the infrared spectrum, molecular weight and monosaccharide composition were analyzed. Afterwards, the antiviral effect of PCPs against PEDV on IPEC-J2 cells was studied by MTT method and real-time PCR method. Additionally, the effects of PCPs on PEDV adsorption, penetration and replication were analyzed by real-time PCR method. Furthermore, we also investigate whether the anti-oxidative effects of PCPs were important to the anti-PEDV activities.

RESULTS

Four polysaccharides were obtained and named as PCP1.1 (31.3 kDa), PCP1.2 (3.5 kDa), PCP2.1 (9.1 kDa) and PCP2.2 (8.3 kDa). PCP1.1, PCP1.2 and PCP2.1 were composed of fucose, arabinose, galactose, glucose, mannose, galacturonic acid and glucuronic acid; and PCP2.2 was composed of arabinose, galactose, glucose, galacturonic acid and glucuronic acid. All PCPs showed anti-PEDV activities. PCP1.1 and PCP1.2 inhibited PEDV replication, while PCP2.1 and PCP2.2 inhibited PEDV penetration and replication. All PCPs showed anti-oxidative effects, which were important to the anti-PEDV activities.

CONCLUSIONS

The treatment effect of Pogostemon cablin (Blanco) Benth. on porcine epidemic diarrhea might be related to the anti-PEDV effect of PCPs. Furthermore, the anti-oxidative effects of PCPs play important roles in their antiviral activities against PEDV.

Anti-feline immunodeficiency virus reverse transcriptase properties of some medicinal and edible mushrooms

Background and Aim

Feline immunodeficiency virus (FIV) causes AIDS-like symptoms in domestic and wild cats. Treatment of infected cats has been performed using human anti-HIV drugs, which showed some limitations. This study aimed to determine the anti-FIV potential of some mushrooms.

Materials and Methods

A total of 17 medicinal and edible mushrooms were screened to find their inhibitory effect against FIV reverse transcriptase (FIV-RT). Three solvents, water, ethanol, and hexane, were used to prepare crude mushroom extracts. Fluorescence spectroscopy was used to perform relative inhibition and 50% inhibitory concentrations (IC₅₀) studies.

Results

The ethanol extract from dried fruiting bodies of Inonotus obliquus showed the strongest inhibition with an IC₅₀ value of 0.80±0.16 μg/mL. The hexane extract from dried mycelium of I. obliquus and ethanol and water extracts from fresh fruit bodies of Phellinus igniarius also exhibited strong activities with the IC₅₀ values of 1.22±0.20, 4.33±0.39, and 6.24±1.42 μg/mL, respectively. The ethanol extract from fresh fruiting bodies of Cordyceps sinensis, hexane extracts from dried mycelium of I. obliquus, ethanol extracts of Ganoderma lucidum, hexane extracts of fresh fruiting bodies of Morchella esculenta, and fresh fruiting bodies of C. sinensis showed moderate anti-FIV-RT activities with IC₅₀ values of 29.73±12.39, 49.97±11.86, 65.37±14.14, 77.59±8.31, and 81.41±17.10 μg/mL, respectively. These mushroom extracts show anti-FIV potential.

Conclusion

The extracts from I. obliquus, P. igniarius, C. sinensis, and M. esculenta showed potential anti-FIV activity.

Inonotus obliquus - from folk medicine to clinical use

The Inonotus obliquus (I. obliquus) mushroom was traditionally used to treat various gastrointestinal diseases. For many years, mounting evidence has indicated the potential of I. obliquus extracts for treatment of viral and parasitic infections. Furthermore, substances from I. obiquus have been shown to stimulate the immune system. The most promising finding was the demonstration that I. obliquus has hypoglycemic and insulin sensitivity potential. This review summarizes the therapeutic potential of I. obliquus extracts in counteracting the progression of cancers and diabetes mellitus as well as their antiviral and antiparasitic activities and antioxidant role. As shown by literature data, various authors have tried to determine the molecular mechanism of action of I. obliquus extracts. Two mechanisms of action of I. obliquus extracts are currently emerging. The first is associated with the broad-sense impact on antioxidant enzymes and the level of reactive oxygen species (ROS). The other is related to peroxisome proliferator-activated receptor gamma (PPARγ) effects. This receptor may be a key factor in the anti-inflammatory, antioxidant, and anti-cancer activity of I. obliquus extracts. It can be concluded that I. obliquus fits the definition of functional food and has a potentially positive effect on health beyond basic nutrition; however, studies that meet the evidence-based medicine (EBM) criteria are needed.

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Extracts or polysaccharides from I. obliquus exhibit an anti-cancer potential in vitro.

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Extracts or polysaccharides from I. obliquus exhibit anti-inflammation potential.

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Extracts or polysaccharides from I. obliquus exhibit hypoglycemic and insulin sensitivity potential.

Nitazoxanide protects cats from feline calicivirus infection and acts synergistically with mizoribine in vitro

Feline calicivirus (FCV) is a highly contagious pathogen that causes acute upper respiratory infections and oral disease in cats, thus seriously endangering feline health. Recently, there have been outbreaks of particularly virulent variant strains of FCV, which can cause both acute symptoms and fatal systemic disease. The discovery of effective antiviral agents to treat FCV infection is, therefore, gradually assuming increased importance. In this study, we showed that both nitazoxanide and mizoribine had antiviral activity in F81 cells infected with different strains of FCV and also demonstrated a synergistic effect between the two drugs. Experiments in cats challenged with FCV showed that nitazoxanide significantly reduced the clinical symptoms of FCV infection, reduced viral load in the trachea and lungs, and reduced viral shedding. Our results showed that nitazoxanide and mizoribine could potentially be used as therapeutic agents to treat FCV infection.