Exopolysaccharide of Laetiporus sulphureus var. miniatus downregulates LPS-induced production of NO, PGE₂, and TNF-α in BV2 microglia cells via suppression of the NF-κB pathway

N-Acetylcysteine Suppresses Microglial Inflammation and Induces Mortality Dose-Dependently via Tumor Necrosis Factor-α Signaling

N-acetylcysteine (NAC) is an antioxidant that prevents tumor necrosis factor (TNF)-α-induced cell death, but it also acts as a pro-oxidant, promoting reactive oxygen species independent apoptosis. Although there is plausible preclinical evidence for the use of NAC in the treatment of psychiatric disorders, deleterious side effects are still of concern. Microglia, key innate immune cells in the brain, play an important role in inflammation in psychiatric disorders. This study aimed to investigate the beneficial and deleterious effects of NAC on microglia and stress-induced behavior abnormalities in mice, and its association with microglial TNF-α and nitric oxide (NO) production. The microglial cell line MG6 was stimulated by Escherichia coli lipopolysaccharide (LPS) using NAC at varying concentrations for 24 h. NAC inhibited LPS-induced TNF-α and NO synthesis, whereas high concentrations (≥30 mM) caused MG6 mortality. Intraperitoneal injections of NAC did not ameliorate stress-induced behavioral abnormalities in mice, but high-doses induced microglial mortality. Furthermore, NAC-induced mortality was alleviated in microglial TNF-α-deficient mice and human primary M2 microglia. Our findings provide ample evidence for the use of NAC as a modulating agent of inflammation in the brain. The risk of side effects from NAC on TNF-α remains unclear and merits further mechanistic investigations.

SPS, a sulfated galactoglucan of Laetiporus sulphureus, exhibited anti-inflammatory activities

Laetiporus sulphureus is an edible and medicinal mushroom. A sulfated galactoglucan (SPS) was isolated by the papain method. Polysaccharides (PS) were isolated by hot water and ethanol precipitation. The medium molecular weight SPS of 100 to 1000 kDa accounted for over half of the SPS mixture. Fucose, galactose, glucose, and mannose were the major monosaccharides in SPS and PS. The amount of sulfate in SPS was 1.09 mmol/g. SPS showed inhibition of tumor necrosis factor-α (TNF-α) release and reversed IκB degradation in LPS-induced RAW264.7 macrophages. The suppression of TNF-α secretion by SPS was through inhibiting the phosphorylation of AKT/extracellular signal-regulated kinases (ERK), p38, and c-Jun N-terminal kinase (JNK). A purified SPS, named SPS-3, was proven to inhibit the LPS-induced phosphorylation of AKT, ERK, and p-38 in RAW264.7 cells. The suppression of interleukin 6 (IL-6) and transforming growth factor beta (TGFβ) secretion by PS was through inhibiting LPS-induced phosphorylation of p-38 and TGF-β receptor II (TGFRII) signaling pathways. This study demonstrates that the isolated SPS and PS from L. sulphureus possessed good anti-inflammatory activity for dietary supplements and functional food.

Ergosta-7,9(11),22-trien-3β-ol Alleviates Intracerebral Hemorrhage-Induced Brain Injury and BV-2 Microglial Activation

Intracerebral hemorrhage (ICH) is a devastating neurological disorder characterized by an exacerbation of neuroinflammation and neuronal injury, for which few effective therapies are available at present. Inhibition of excessive neuroglial activation has been reported to alleviate ICH-related brain injuries. In the present study, the anti-ICH activity and microglial mechanism of ergosta-7,9(11),22-trien-3β-ol (EK100), a bioactive ingredient from Asian medicinal herb Antrodia camphorate, were evaluated. Post-treatment of EK100 significantly attenuated neurobehavioral deficit and MRI-related brain lesion in the mice model of collagenase-induced ICH. Additionally, EK100 alleviated the inducible expression of cyclooxygenase (COX)-2 and the activity of matrix metalloproteinase (MMP)-9 in the ipsilateral brain regions. Consistently, it was shown that EK100 concentration-dependently inhibited the expression of COX-2 protein in Toll-like receptor (TLR)-4 activator lipopolysaccharide (LPS)-activated microglial BV-2 and primary microglial cells. Furthermore, the production of microglial prostaglandin E₂ and reactive oxygen species were attenuated by EK100. EK100 also attenuated the induction of astrocytic MMP-9 activation. Among several signaling pathways, EK100 significantly and concentration-dependently inhibited activation of c-Jun N-terminal kinase (JNK) MAPK in LPS-activated microglial BV-2 cells. Consistently, ipsilateral JNK activation was markedly inhibited by post-ICH-treated EK100 in vivo. In conclusion, EK100 exerted the inhibitory actions on microglial JNK activation, and attenuated brain COX-2 expression, MMP-9 activation, and brain injuries in the mice ICH model. Thus, EK100 may be proposed and employed as a potential therapeutic agent for ICH.

Mitigating Effect of Lindera obtusiloba Blume Extract on Neuroinflammation in Microglial Cells and Scopolamine-Induced Amnesia in Mice

Lindera obtusiloba Blume (family, Lauraceae), native to Northeast Asia, has been used traditionally in the treatment of trauma and neuralgia. In this study, we investigated the neuroinflammatory effect of methanol extract of L. obtusiloba stem (LOS-ME) in a scopolamine-induced amnesia model and lipopolysaccharide (LPS)-stimulated BV2 microglia cells. LOS-ME downregulated the expression of inducible nitric oxide synthase (iNOS), cyclooxygenase (COX)-2, inflammatory cytokines, and inhibited the phosphorylation of nuclear factor kappa-B (NF-ĸB) and extracellular signal-regulated kinase (ERK) in LPS-stimulated BV2 cells. Male C57/BL6 mice were orally administered 20 and 200 mg/kg of LOS-ME for one week, and 2 mg/kg of scopolamine was administered intraperitoneally on the 8th day. In vivo behavioral experiments (Y-maze and Morris water maze test) confirmed that LOS-ME alleviated cognitive impairments induced by scopolamine and the amount of iNOS expression decreased in the hippocampus of the mouse brain. Microglial hyper-activation was also reduced by LOS-ME pretreatment. These findings suggest that LOS-ME might have potential in the treatment for cognitive improvement by regulating neuroinflammation.

Mycelial culture extracts of selected wood-decay mushrooms as a source of skin-protecting factors

OBJECTIVES

This study analyzed the content of substances with cosmetologic properties in the extracts obtained from the mycelial cultures of Ganoderma applanatum, Laetiporus sulphureus, and Trametes versicolor. The effect of these extracts on the inhibition of tyrosinase and hyaluronidase was determined, and their values of sun protection factor (SPF) were calculated.

RESULTS

The total amount of phenolic acids in the extracts ranged from 2.69 (G. applanatum) to 10.30 mg/100 g dry weight (T. versicolor). The total amount of sterols was estimated at 48.40 (T. versicolor) to 201.04 mg/100 g dry weight (L. sulphureus), and that of indoles at 2.90 (G. applanatum) to 16.74 mg/100 dry weight (L. sulphureus). Kojic acid was determined in the extracts of L. sulphureus and G. applanatum. It was observed that L. sulphureus extract caused dose-dependent inhibition of hyaluronidase, while all the extracts inhibited tyrosinase. The extract of G. applanatum exhibited an SPF value of ~ 9.

CONCLUSIONS

The results showed that the mycelial cultures of the studied species may be used as an alternative source of substances used in cosmetology.

The Laetiporus sulphureus Fermented Product Enhances the Antioxidant Status, Intestinal Tight Junction, and Morphology of Broiler Chickens

Simple Summary

This study investigated the effects of the Laetiporus sulphureus fermented product (FL) as a feed supplement on antioxidant activities, intestinal Tight Junction (TJ) mRNA expression, and the intestinal morphology of broiler chickens. FL supplementation could potentially enhance the feed conversion ratio in broilers by improving their antioxidative status, TJ mRNA expression, and intestinal morphology. Broilers supplemented with 5% FL exhibited the best overall results on improving antioxidant status, TJ mRNA expression, and intestinal morphology.

Abstract

The Laetiporus sp. is a fungal species that is traditionally used for medicinal purposes. This study investigated the effects of the Laetiporus sulphureus fermented product (FL) as a feed supplementation on the antioxidant activities, the intestinal Tight Junction (TJ) mRNA expression, and the intestinal morphology of broiler chickens. Four-hundred one-day-old male broilers (Ross 308) were randomly allocated to five experimental diets: (1) a corn-soybean meal basal diet (control), (2) a basal diet replaced with 5% Wheat Bran (5% WB), (3) a basal diet replaced with 10% WB (10% WB), (4) a basal diet replaced with 5% FL (5% FL), and (5) a basal diet replaced with 10% FL (10% FL). The FL-supplemented groups exhibited a better feed conversion ratio in the overall experimental period compared to the WB and control groups. The serum antioxidant profiles of 35-day-old broilers showed that, compared to the control and 10% WB groups, the 5% FL supplementation group had a significantly increased superoxide dismutase activity, while it down-regulated the concentration of malondialdehyde in the serum (p < 0.05). The assessment of selected antioxidant gene expression showed that the 5% FL group significantly elevated heme oxygenase-1 and nuclear factor erythroid 2–related factor 2 expression, compared to the control and WB groups (p < 0.05). Furthermore, both of the FL supplemented groups had a significantly higher expression of glutathione peroxidase and catalase, compared to that of the WB and control groups in the jejunum (p < 0.05). The TJ mRNA expression in the jejunum showed that 5% FL significantly elevated the zonula occludens-1, claudin-1, and mucin-2 expression (p < 0.05), while 5% and 10% FL supplementation significantly improved OCLN expression in both the jejunum and ileum, compared to control group (p < 0.05). The intestinal morphology of 35-day-old broilers showed that a 5% FL supplementation significantly increased the villus height in the ileum and jejunum, compared to the WB and control groups (p < 0.05). Moreover, the 5% and 10% FL supplementation groups had a significantly higher villi:crypt ratio in the ileum, compared to the WB and control groups (p < 0.05). To conclude, FL supplementation improved the antioxidative status, the TJ mRNA expression, and the intestinal morphology, and it was accompanied by a lowered feed conversion ratio in broilers. Finally, 5% supplementation had the overall best results in improving the antioxidant status, TJ mRNA expression, and intestinal morphology of broilers.

Laetiporus sulphureus-fermented wheat bran enhanced the broiler growth performance by improving the intestinal microflora and inflammation status

This study investigates the effects of Laetiporus sulphureus–fermented wheat bran (LS) as a feed supplementation on the immunomodulative properties in broiler chickens. Crude phenolic compounds, crude polysaccharides, crude triterpenoids, and ergosterol were determined in LS water extracts. In animal experiments, 400 male broilers (Ross 308) were randomly assigned into 5 groups fed with a corn–soybean–based diet (control) and a control diet replaced with 5% wheat bran (WB), 10% WB, 5% LS, and 10% LS, respectively. Each group had 4 replicates and 20 birds per pen (total of 80 birds/treatment). The results showed that the 5% LS–supplemented group had significantly higher BW in the finisher phase (22–35 D). Better feed conversion ratio (P < 0.05) of LS-supplemented groups was observed in both the finisher phase and the overall experimental period. The LS-supplemented groups had significantly lower coliform counts in the ileum than the other treatment and control groups (P < 0.05). The results of serum immunoglobulin showed that LS supplementation significantly increased serum IgA concentration compared with the control and WB-supplemented groups (P < 0.05). Simultaneously, ileal IgA contents of the LS groups were significantly higher than in the WB and control groups (P < 0.05). Regarding proinflammatory cytokines, serum tumor necrosis factor alpha and IL-6 in the LS-supplemented groups were significantly lower than those in the 10% WB group (P < 0.05), whereas serum tumor necrosis factor alpha and IL-1β in the 5% LS group were significantly lower than in both the control and WB-supplemented groups (P < 0.05). An investigation on the effects of LS on immune-related genes in broiler showed that chickens supplemented with 5% LS had lower levels of liver and jejunum IL-1β and NF-κB mRNA compared with the control group and WB groups (P < 0.05). In conclusion, LS supplementation can potentially enhance growth performance of broilers by improving intestinal microflora and inflammation status.

European medicinal mushrooms: Do they have potential for modern medicine? - An update

BACKGROUND

The application of mushrooms for health purposes has a long tradition and is very common in Asian countries. This trend is also becoming increasingly popular in the western hemisphere. However, mushrooms from European tradition are being treated in a restrained manner despite having significant potential as drugs or as sources of pure bioactive substances.

AIM

The present review provides an overview of the most important mushrooms used in European ethnomedical traditions and explores their pharmacological potential and the challenges for the development of new drugs from these sources of natural products.

METHOD

Mushroom species were selected based on information in old herbal books and dispensaries, uninterrupted use and scientific literature in the PubMed database up to June 2019.

RESULTS

Traditional experiences and modern studies have demonstrated that medical mushrooms used in European traditions have promising distinct pharmacological potential mediated through defined mechanisms (anti-tumour, anti-inflammatory, anti-oxidative and anti-bacterial). However, the number of modern chemical, biological and pharmacological studies remains relatively small, and some mushroom species have not been studied at all. Unfortunately, no valid clinical studies can be found. Unlike the case with herbal and fungal drugs from traditional Chinese medicine, we are far from comprehensively exploring this potential.

CONCLUSIONS

Mushrooms from traditional European medicine have the potential to be used in modern medicine. Considerable research, interdisciplinary collaboration, involvement of the pharmaceutical industry, time and money are necessary to explore this potential not only in the form of dietary supplements but also in the form of approved drugs.

Antioxidant and Hepatoprotective Activities of Polysaccharides from Spent Mushroom Substrates (Laetiporus sulphureus) in Acute Alcohol-Induced Mice

In order to contribute to the exploitation and utilization of spent mushroom substrates (SMS) of Laetiporus sulphureus, hot-water-extractable polysaccharides (H-SMPS) and enzymatic-extractable polysaccharides (E-SMPS) were successfully isolated from SMS of L. sulphureus. Both H-SMPS and E-SMPS were found to have high reducing power and potential scavenging activities against hydroxyl, DPPH, and superoxide anion radicals. In vivo assays showed that the administration of H-SMPS and E-SMPS has potential hepatoprotective effects against alcohol-induced alcoholic liver disease (ALD), possibly brought about by improving liver function, increasing antioxidant status, and reducing lipid peroxidation. Furthermore, monosaccharide composition analysis showed that fucose may play a vital role in guaranteeing stronger hepatoprotection. These results may provide references for the exploitation of the SMS of L. sulphureus as a source of H-SMPS and E-SMPS, which in turn can be used as functional foods or natural drugs for the prevention of ALD and other liver diseases.

3β-Angeloyloxy-8β,10β-dihydroxyeremophila-7(11)-en-12,8α-lactone Inhibits Lipopolysaccharide-Induced Nitric Oxide Production in RAW264.7 Cells

Farfugium japonicum (L.) KITAM, named "Lian-Peng-Cao" in China, has been traditionally used in Chinese folk medicine to treat sore throat, cold and cough due to its anti-inflammatory properties. In this study, the anti-inflammatory action of 3β-angeloyloxy-8β,10β-dihydroxyeremophila-7(11)-en-12,8α-lactone (FJ1) isolated from Farfugium japonicum and its molecular mechanism in RAW264.7 cells were investigated. 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay showed that FJ1 with or without 3 µg/mL lipopolysaccharide (LPS) had no significant cytotoxicity in RAW264.7 cells. The production of nitric oxide (NO) was identified with a Griess reagent kit. The mRNA expression of inducible nitric oxide synthase (iNOS) and cytokines, including tumor necrosis factor α (TNF-α) and cyclooxygenase-2 (COX-2), was measured by real-time polymerase chain reaction (PCR). Reactive oxygen species (ROS) production was detected by flow cytometry analysis. Western blot was used to examine the protein expression of nuclear factor-kappa B (NF-κB)/p65, inhibitor of kappa B (IκB)-α, phosphorylated IκB-α (p-IκB-α), mitogen-activated protein kinase (MAPK) molecules, iNOS, and TNF-α. We discovered that FJ1 possesses anti-inflammatory effects that inhibit the release of LPS-stimulated pro-inflammatory cytokines, including NO and ROS. The molecular mechanism of FJ1-mediated anti-inflammation is associated with decreasing phosphorylation of MAPK molecules, including extracellular signal-related kinase 1/2 (ERK1/2), p38 MAPK, and c-Jun NH2-terminal kinase (JNK), FJ1 also reverses IκB degradation and attenuates the mRNA and protein expression of NF-κB-related downstream inducible enzymes and cytokines, such as iNOS, TNF-α in RAW264.7 cells. The results suggest that FJ1 has anti-inflammatory properties, which indicates that F. japonicum can be utilized to treat inflammatory diseases. The potential mechanism is associated with the NF-κB and MAPK activation pathways in LPS-stimulated macrophages.

Sesquiterpenes from Essential Oils and Anti-Inflammatory Activity

This review is aimed at presenting relevant information on the therapeutic potential of essential oil sesquiterpenes with anti-inflammatory activity. The data reviewed provide a basis for seeking new anti-inflammatory drugs from natural products that do not exhibit the undesirable side effects often displayed by anti-inflammatory drugs. In this review the experimental models, possible mechanisms of action, and chemical structures of 12 sesquiterpenes are presented.

Resveratrol induces the expression of interleukin-10 and brain-derived neurotrophic factor in BV2 microglia under hypoxia

Microglia are the resident macrophages of the central nervous system (CNS) and play an important role in neuronal recovery by scavenging damaged neurons. However, overactivation of microglia leads to neuronal death that is associated with CNS disorders. Therefore, regulation of microglial activation has been suggested to be an important target for treatment of CNS diseases. In the present study, we investigated the beneficial effect of resveratrol, a natural phenol with antioxidant effects, in the microglial cell line, BV2, in a model of hypoxia injury. Resveratrol suppressed the mRNA expression of the pro-inflammatory molecule, tumor necrosis factor-α, and promoted the mRNA expression of the anti-inflammatory molecule, interleukin-10, in BV2 microglia under hypoxic conditions. In addition, resveratrol inhibited the activation of the transcription factor, nuclear factor kappa-light-chain enhancer of activated B cells (NF-κB), which is upstream in the control of inflammatory reactions in hypoxia-injured BV2 microglia. Moreover, resveratrol promoted the expression of brain-derived neurotrophic factor (BDNF) in BV2 microglia under hypoxic stress. Overall, resveratrol may promote the beneficial function of microglia in ischemic brain injury.

European medicinal polypores--a modern view on traditional uses

ETHNOPHARMACOLOGICAL RELEVANCE

In particular five polypore species, i.e. Laetiporus sulphureus, Fomes fomentarius, Fomitopsis pinicola, Piptoporus betulinus, and Laricifomes officinalis, have been widely used in central European folk medicines for the treatment of various diseases, e.g. dysmenorrhoea, haemorrhoids, bladder disorders, pyretic diseases, treatment of coughs, cancer, and rheumatism. Prehistoric artefacts going back to over 5000 years underline the long tradition of using polypores for various applications ranging from food or tinder material to medicinal-spiritual uses as witnessed by two polypore species found among items of Ötzi, the Iceman. The present paper reviews the traditional uses, phytochemistry, and biological activity of the five mentioned polypores.

MATERIALS AND METHODS

All available information on the selected polypore taxa used in traditional folk medicine was collected through evaluation of literature in libraries and searches in online databases using SciFinder and Web of Knowledge.

RESULTS

Mycochemical studies report the presence of many primary (e.g. polysaccharides) and secondary metabolites (e.g. triterpenes). Crude extracts and isolated compounds show a wide spectrum of biological properties, such as anti-inflammatory, cytotoxic, and antimicrobial activities.

CONCLUSIONS

The investigated polypores possess a longstanding ethnomycological tradition in Europe. Here, we compile biological results which highlight their therapeutic value. Moreover, this work provides a solid base for further investigations on a molecular level, both compound- and target-wise.

Sesquiterpene dimer (DSF-52) from Artemisia argyi inhibits microglia-mediated neuroinflammation via suppression of NF-κB, JNK/p38 MAPKs and Jak2/Stat3 signaling pathways

Microglia-involved neuroinflammation is thought to promote brain damage in various neurodegenerative disorders. Therefore, novel therapeutics suppressing microglia over-activation could prove useful for neuroprotection in inflammation-mediated neurodegenerative diseases. DSF-52 is a novel sesquiterpene dimer compound isolated from medical plant Artemisia argyi by our group. In this study, we investigated whether DSF-52 inhibited the neuroinflammatory responses in lipopolysaccharide (LPS)-activated microglia. Our findings showed that DSF-52 inhibited the production of nitric oxide (NO), prostaglandin E2 (PGE2), tumor necrosis factor-α (TNF-α), as well as mRNA expression of inducible nitric oxide synthase (iNOS), cyclooxygenase 2 (COX-2), interleukin-1β (IL-1β), granulocyte-macrophage colony-stimulating factor (GM-CSF) and macrophage inflammatory protein-1α (MIP-1α) in LPS-activated BV-2 microglia. Moreover, DSF-52 markedly up-regulated mRNA levels of anti-inflammatory cytokine IL-10. Mechanism study indicated that DSF-52 suppressed Akt/IκB/NF-κB inflammation pathway against LPS treatment. Also, DSF-52 down-regulated the phosphorylation levels of JNK and p38 MAPKs, but not ERK. Furthermore, DSF-52 blocked Jak2/Stat3 dependent inflammation pathway through inhibiting Jak2 and Stat3 phosphorylation, as well as Stat3 nuclear translocation. We concluded that the inhibitory ability of DSF-52 on microglia-mediated neuroinflammation may offer a novel neuroprotective modality and could be potentially useful in inflammation-mediated neurodegenerative diseases.

Effect of glucans from Caripia montagnei mushroom on TNBS-induced colitis

In this study, we evaluated the effect of different doses of polysaccharides extracted from Caripia montagnei mushroom at different intervals of treatment on colonic injury in the model of colitis induced by 2,4,6-trinitrobenzene sulfonic acid (TNBS). The FT-IR analysis and NMR showed that the polysaccharides from this species of mushroom are composed of α- and β-glucans. The colonic damage was evaluated by macroscopic, histological, biochemical and immunologic analyses. The results showed the reduction of colonic lesions in all groups treated with the glucans. Such glucans significantly reduced the levels of IL-6 (50 and 75 mg/kg, p < 0.05), a major inflammatory cytokine. Biochemical analyses showed that the glucans from C. montagnei acted on reducing levels of alkaline phosphatase (75 mg/kg, p < 0.01) and myeloperoxidase (p < 0.001), a result confirmed by the reduction of cellular infiltration observed microscopically. The increase of catalase activity possibly indicates a protective effect of these glucans on colonic tissue, confirming their anti-inflammatory potential.

Licorice-derived dehydroglyasperin C increases MKP-1 expression and suppresses inflammation-mediated neurodegeneration

Recent studies have demonstrated that microglial hyperactivation-mediated neuroinflammation is involved in the pathogenesis of several neurodegenerative diseases. Thus, inhibiting microglial production of the neurotoxic mediator tumor necrosis factor-α (TNF-α) is considered a promising strategy to protect against neurodegeneration. Here, we investigated the inhibitory effect of licorice-derived dehydroglyasperin C (DGC) on lipopolysaccharide (LPS)-induced TNF-α production and inflammation-mediated neurodegeneration. We found that DGC pre-treatment attenuated TNF-α production in response to LPS stimulation of BV-2 microglia. DGC pre-treatment attenuated LPS-induced inhibitor of κB-α (IκB-α) and p65 phosphorylation and decreased the DNA binding activity of nuclear factor-κB (NF-κB). DGC pre-treatment also inhibited LPS-mediated phosphorylation of p38 mitogen-activated protein kinases (MAPKs) and extracellular signal-regulated kinase (ERK). Interestingly, DGC treatment of BV-2 microglia significantly increased MAPK phosphatase 1 (MKP-1) mRNA and protein expression, which is a phosphatase of p38 MAPK and ERK, suggesting that the DGC-mediated increase in MKP-1 expression might inhibit LPS-induced MAPKs and NF-κB activation and further TNF-α production. We also found that LPS-mediated microglial neurotoxicity can be attenuated by DGC. The addition of conditioned media (CM) from DGC- and LPS-treated microglia to neurons helped maintain healthy cell body and neurite morphology and increased the number of microtubule-associated protein 2-positive cells and the level of synaptophysin compared to treatment with CM from LPS-treated microglia. Taken together, these data suggest that DGC isolated from licorice may inhibit microglia hyperactivation by increasing MKP-1 expression and acting as a potent anti-neurodegenerative agent.