Antioxidant activity of polysaccharides extracted from Lentinus edodes mycelia and their protective effects on INS-1 cells / Atividade antioxidante de polissacarídeos extraídos de Lentinus edodes micélio e seus efeitos protectores em células INS-1

The disruption of the delicate balance between the generation of reactive oxygen species (ROS) and antioxidant scavenging systems can lead to many health problems. Polysaccharides extracted from fungi fruit body and myceliums have several potential health benefits. In this study, the antioxidant capacity and cell protective effects of a polysaccharide isolated from Lentinus edodes mycelia (LMP) were investigated. The antioxidant properties of LMP were screened using radical scavenging (1, 1-diphenyl-2-picrylhydrazyl (DPPH), hydroxyl, and superoxide anion), reducing power and inhibition of lipid peroxidation assays. Intracellular reactive oxygen species (ROS), in response to H2O2, was determined by the dichloro-dihydro-fluorescein diacetate (DCFH-DA) assay. Rat insulinoma (INS-1) cells apoptosis was detected using flow cytometry analysis. The results showed that LMP exhibited significantly strong radical scavenging activity. At the concentration of 2.0 mg mL-1, DPPH radical, hydroxyl radical, and superoxide anion radical scavenging rates are 80.32 ± 2.58%, 92.56 ± 3.11% and 93.73 ± 2.82%, respectively. The reducing power and inhibition of lipid peroxidation activity of LMP were as strong as the positive control. LMP alleviated the intracellular reactive oxygen species level and inhibited islet cell apoptosis significantly. The results open perspectives for studies of LMP in the treatment of diabetes.

O estresse oxidativo tem uma função biológica importante em muitos organismos. A ruptura do equilíbrio delicado entre a geração de espécies reativas de oxigênio (ROS) e sistemas de eliminação de antioxidantes pode levar a muitos problemas de saúde. Polissacarídeos extraídos do corpo fungos frutas e micélio têm vários benefícios potenciais para a saúde. Neste estudo, foram investigados os efeitos celulares e capacidade de proteção antioxidante de um polissacarídeo isolado a partir de Lentinus edodes micélios (LMP). As propriedades antioxidantes da LMP foram rastreadas utilizando eliminação de radicais (1, 1-difenil-2-picrilhidrazil (DPPH), hidroxilo e anião superóxido), e a redução da potência de inibição de ensaios de peroxidação lipídica. Espécies reativas de oxigénio intracelulares (ROS), em resposta ao H2O2, foi determinada pelo ensaio de diacetato de dicloro-di-hidro-f luoresceina (DCFH-DA). INS-1 células a apoptose foi detectada utilizando análise de citometria de fluxo. Os resultados mostraram que LMP exibiu significativamente forte atividade de eliminação de radicais. Na concentração de 2 mg mL-1, DPPH radical, radical hidroxilo e anião superóxido velocidades de eliminação de radicais livres são 80,32 ± 2,58%, 92,56 ± 3,11% 93,73 ± 2,82%, respectivamente. O poder redutor e inibição da peroxidação lipídica de LMP foram tão forte quanto o controlo positivo. LMP aliviou a nível de espécies reativas de oxigênio intracelular e apoptose de células da ilhota inibiu significativamente. Sugere-se que LMP pode ser utilizado como um reagente complementar para a diabetes a prevenção e terapia.

Lentinus edodes Suppresses Allergen-Induced Airway Hyperresponsiveness and Inflammation by Downregulating Nuclear Factor-kappa B Activity in a Murine Model of Allergic Asthma / 체질인류학회지

Medicinal mushrooms have been shown to have profound health promoting benefits. Among them, Lentinus edodes is well-known to have anti-tumor, anti-inflammatory, and immunomodulatory effects. The aim of the present study is to evaluate whether Lentinus edodes ethanol extract (LE) inhibit airway inflammatory response in a murine asthma model induced by exposure to ovalbumin (OVA). The pretreatment of LE substantially attenuated airway hyperresponsiveness and eosinophilic inflammation in OVA-challenged mice. In addition, the increased levels of Th2 cytokines (IL-4, IL-5, and IL-13), eotaxin, and adhesion molecules in bronchoalveolar lavage fluids at 48 h after OVA inhalation was significantly reduced by the administration of LE. Furthermore, LE suppressed OVA-induced activation of nuclear factor-kappa B and p38 mitogen-activated protein kinase in lung tissues. Taken together, it is proposed that LE may serve as an effective therapeutic agent for allergic airway disease.

Preparation of polysaccharide complex and its indirect antitumor activity in vitro / 吉林大学学报(医学版)

Objective To extract the Ginseng polysaccharide (GPS), polysaccharides of Tricholoma matsutake (PTM)and polysaccharide of Lentinus edodes (PLE)from gingeng, tricholoma matsutake and lentinus edodes respectively,and to analyze and identify their structures,and to prepare their complex,and to study the indirect antitumor activity invitro of polysaccharide complex.Methods The polysaccharides were extracted with hot water and precipitated by ethanol.The carbohydrate levels were determined by the method of phenol-sulfuric acid.The m-hydroxyphenyl method was used to determine the levels of uronic acid, and the national standard method was used to determine the levels of starch.Infrared spectroscope and chemical methods were performed to analyze their structures. Orthogonal experiment was used to study mixing methods. Cytotoxic T lymphocyte experiment and LDH release assay were performed to detect the influence of polysaccharide complex of GPS,PTM,and PLE in the CTL killing activity,and its indirect killing effect on the P815 cells.Results The extraction rates of GPS,PTM, and PLE were 8.85%,9.40%,and 10.50%;the levels of total polysaccharides were 62.96%,59.13%,and 33.86%;the levels of uronic acid were 16.44%,9.37%,and 16.44%;the starch levels were 7.26%,2.80%,and 3.77%,respectively.The identification results showed that the polysaccharides were obstrained.When the quality ratio of the three kinds of polysaccharides was 1∶1∶1 and the concentration was 600 mg·L-1 ,the CTL cytotoxicity was the highest.Conclusion The polysaccharide complex is obtained,identified and characterized. Polysaccharide complex can enhance the cytotoxicity of CTL and has the indirectly inhibitory effect on the proliferation of P815 cells.

Review on chemistry and anti-tumor effect of lentinan / 中国药学杂志

OBJECTIVE: To introduce the progress on the study of lentinan chemistry and anti-tumor effect and provide references for research and clinical applications. METHODS: Reviewed and analyzed many literatures of lentinan, summarized them compres-sively and introduced the progress on the extraction and purification of lentinan, structural analysis and anti-tumor effect in recent years. RESULTS: As the extraction and purification methods for lentinan were different, the polysaccharide compositions and structures were different, and the main forms were homopolysaccharide(glucan) and heteropolysaccharide. And its anti-tumor effects were related to immune enhancement, inhibition of tumor growth effect, synergistic anti-tumor chemotherapy and so on. CONCLUSION: Chemical properties of lentinan is closely related with the anti-tumor effect, and further in-depth research on the structure-activity relationships of lentinan is needed to provide better scientific basis for the comprehensive development and application of lentinan.

Shiitake Mushroom: A Tool of Medicine.

Medicinal mushrooms have an established history of use in traditional oriental therapies. Contemporary research has validated and documented much of the ancient knowledge. Over the last three decades, the interdisciplinary fields of science that study medicinal mushrooms has sprung up and has increasingly demonstrated the potent and unique properties of compounds extracted from a range of species. Currently, the field is being developed into a very fruitful area. Modern clinical practice in Japan, China, Korea and other Asian countries rely on mushroom-derived preparations. Mushrooms have been studied for nutritional and medical purposes for its various potential anti-tumoral and immunomodulatory componests like polysaccharides that have been identified. For medical purposes, mushrooms have been consumed to prevent cancer and cardiac diseases, to improve blood circulation and to reduce blood cholesterol level. Some of these mushrooms have also been used for the treatment of physical and emotional stress, osteoporosis, gastric ulcers and chronic hepatitis, for the improvement of the quality of life of patients with diabetes and especially for the stimulation of immunity. Shiitake has a history of medicinal uses. The mushroom is used as anticarcinogenic, antiinflammatory, antioxidant, antifungal, antibacterial, antiviral as well as antithrombotic in cardiovascular disorders. This article has been written to throw some light on Shiitake mushroom which has many nutritional values. Many Shiitake preparations came in market containing the active ingredients which can replace many other marketed synthetic medicines and may prove to have promising results with fewer side effects.

Isolation of a laccase with HIV-1 reverse transcriptase inhibitory activity from fresh fruiting bodies of the Lentinus edodes (Shiitake mushroom).

A laccase with a molecular mass of 67 kDa and inhibitory activity toward HIV-1 reverse transcriptase (IC50 = 7.5 M) was isolated from fresh fruiting bodies of the Lentinus edodes (Shiitake mushroom). Its characteristics were compared with those of laccases from cultured mushroom mycelia reported earlier. The laccase was unadsorbed on DEAE-cellulose, Affi-gel blue gel and CM-cellulose, but was adsorbed on Con A-Sepharose. About 50-fold purification was achieved with a 19.2% yield of the enzyme. The activity of the enzyme increased steadily from 20°C to 70°C. The activity disappeared after exposure to the boiling temperature for 10 min. Its optimal pH was 4 and very little enzyme activity remained at and above pH 10. The laccase inhibited HIV-1 reverse transcriptase with an IC50 of 7.5 M, but did not demonstrate any antifungal or anti-proliferative activity.

Antihyperlipidemic Effect of Dietary Lentinus edodes on Plasma, Feces and Hepatic Tissues in Hypercholesterolemic Rats

We investigated diet supplementation with shiitake mushroom fruiting bodies on biochemical and histological changes in hypercholesterolemic rats. Six-wk old female Sprague-Dawley albino rats were divided into three groups of 10 rats each. A diet containing 5% Lentinus edodes fruiting bodies given to hypercholesterolemic rats reduced plasma total cholesterol, triglyceride, low-density lipoprotein (LDL), total lipid, phospholipids, and the LDL/high-density lipoprotein ratio by 34.33, 53.21, 75.00, 34.66, 25.73, and 71.43%, respectively. Feeding mushroom also significantly reduced body weight in hypercholesterolemic rats. However, it had no detrimental effects on plasma albumin, total bilirubin, direct bilirubin, creatinine, blood urea nitrogen, uric acid, glucose, total protein, calcium, sodium, potassium, chloride, inorganic phosphate, magnesium, or enzyme profiles. Feeding mushroom increased total lipid and cholesterol excretion in feces. The plasma lipoprotein fraction, separated by agarose gel electrophoresis, indicated that L. edodes significantly reduced plasma beta and pre-beta-lipoprotein but increased alpha-lipoprotein. A histological study of hepatic cells by conventional hematoxylin-eosin and oil red-O staining showed normal findings for mushroom-fed hypercholesterolemic rats. These results suggest that shiitake mushrooms could be recommended as a natural cholesterol lowering substance in the diet.

Protective Effects of a Water-Soluble Extract from Culture Medium of Lentinus Edodes Mycelia against Neuronal Damage after Hypoxia-Ischemia in Mice / 日本補完代替医療学会誌

<b>Objective</b>: <i>Lentinus edodes</i> (Shiitake) is a very popular mushroom in Asian cuisine. The water-soluble extract from culture medium of <i>Lentinus edodes</i> mycelia (LEM), which is commercially available as a nutritional supplement, is prepared by hot-water treatment from a solid medium composed of bagasse and defatted-rice bran overgrown for about 4 months with its mycelia. LEM was previously reported to have antioxidant activity and to suppress various oxidative damages. In this study, the neuroprotective effects of 2-week intake of LEM on cerebral ischemic damage induced by hypoxia/ischemia (H/I) followed by reoxygenation in mice were examined.<br> <b>Method</b>: Male C57BL/6J mice were divided into three groups, fed for two weeks with the control laboratory powder chow, 0.5% LEM-contained chow, or 1% LEM-contained chow, respectively. Cerebral ischemic damage was induced in the mice by H/I (i.e., unilateral ligation of the carotid artery and exposure of 8%O₂ for 30 min). Twenty-four hours after H/I, total plasma oxidative stress, neurological deficits, cerebral infarction volume were evaluated in each group. Furthermore, the number of apoptotic cells in ischemic penumbra, the hippocampal CA1 and CA2, and the somatosensory area of the cortex, were analyzed by TUNEL staining and cleaved caspase-3 immunostaining.<br> <b>Results</b>: The infarct area assessed 24-h after H/I was extended to the corpus striatum and cortex in the control mice. Treatment of LEM dose dependently improved plasma oxidative stress, neurological deficits, and cerebral infarction volume. Moreover, LEM decreased the levels of dihydroethidium activity as an index of super oxide production and the number of apoptotic cells in ischemic penumbra.<br> <b>Conclusion</b>: These results show that chronic intake of LEM relieves the hypoxia-induced cerebral ischemic injury, which may be attributed to the antioxidant effects of LEM.<br>

Lentinula edodes (Shiitake) mushroom extract protects against hydrogen peroxide induced cytotoxicty in peripheral blood mononuclear cells.

Lentinula edodes (Berk) Pegler, commonly known as Shiitake mushroom has been used as medicinal food in Asian countries, especially in China and Japan and is believed to possess strong immunomodulatory property. In the present study, the methanolic extract of the fruit bodies of L. edodes was investigated for cytoprotective effect against H2O2-induced cytotoxicity in human peripheral blood mononuclear cells (PBMCs) by measuring the activities of xanthine oxidase (XO) and glutathione peroxidase (GPx) . H2O2 at a concentration of 5 μM caused 50% inhibition of PBMCs viability. The extract improved the PBMC viability and exerted a dose-dependent protection against H2O2-induced cytotoxicity. At 100 μg/ml of extract concentration, the cell viability increased by 60% compared with the PBMCs incubated with H2O2 alone. The extract also inhibited XO activity in PBMC, while showing moderate stimulatory effect on GPx. However, in the presence of H2O2 alone, both the enzyme activities were increased significantly. The GPx activity increased, possibly in response to the increased availability of H2O2 in the cell. When the cells were pretreated with the extract and washed (to remove the extract) prior to the addition of H2O2, the GPx and XO activities as well as the cell viability were comparable to those when incubated with the extract alone. Thus, it is suggested that one of the possible mechanisms via which L. edodes methanolic extract confers protection against H2O2-induced oxidative stress in PBMC is by inhibiting the superoxide-producing XO and increasing GPx activity which could rapidly inactivate H2O2.

The Suppressive Effect of Lentinus Edodes on Renal Scarring Secondary to Pyelonephritis / 대한비뇨기과학회지

PURPOSE: Lentinus edodes is used in both foods and drugs, and is also known to be an antioxidant agent. Some investigators have noted that renal scarring following pyelonephritis is closely related to inflammation or free oxygen radicals, rather than to direct injury due to bacterial infection. The efficiency of the antioxidant agent, lentinus edodes, in preventing the renal scarring caused by experimental pyelonephritis was evaluated in rats. MATERIALS AND METHODS: Twenty eight male Sprague Dawley rats (n=28) were injected into both renal parenchyma with 0.1ml of a solution containing Escherichia coli (10(8)/ml). The control group, consisting of 4 rats, received an injection of isotonic saline instead of the bacterial solution. Three days after surgery, the animals were given the following treatments: in the pyelonephritis group, 7 rats received isotonic saline for 5 days; in the antibiotics treatment group, 6 rats were treated with an antibiotic only, ciprofloxacin, for 5 days. In the lentinus edodes treatment group, 5 rats were treated with lentinus edodes only. In the combined group, 6 rats received both lentinus edodes and ciprofloxacin. The kidneys were harvested 6 weeks after infection, and histopathologically examined for renal scarring. RESULTS: Delayed treatment with antibiotics-only or lentinus edodes-only had no effect on the scarring compared with the untreated controls. However, the addition of lentinus edodes to the delayed antibiotic therapy significantly inhibited the renal scarring compared with the pyelonephritis, antibiotic-only treated and the lentinus edodes-only treated groups (p<0.05). CONCLUSIONS: The administration of lentinus edodes in combination with antibiotics significantly reduced the renal scar formation in pyelonephritis.

Supplementary Effect of Lentinus Edodes on Serum and Hepatic Lipid Levels in Spontaneously Hypertensive Rat

This study was conducted to investigate the supplementary effects of Lentinus edodes on blood pressure and blood lipid levels in the Hypertensive Rat. We supplied 3 kinds of experimental diets (Control; CO, cap of Lentinus edodes; LC, and stipe of Lentinus edodes; LS) to spontaneously hypertensive rats (SHR) for 8 weeks. Diet intake, body weight, organ weights, and serum lipid levels were measured. There was no significant difference in diet intake, and body, liver and epididymal fat pad weights among experimental groups. The levels of systolic and diastolic blood pressure were significantly lower in LC and LS groups than CO group. The concentrations of serum total cholesterol were lower in LC and LS groups than CO group. These results suggested that Lentinus edodes decrease blood pressure levels and serum total cholesterol concentration in the spontaneously hypertensive rats. But these effects of Lentinus edodes didn't show any significant difference between animals fed cap and stipe of this mushroom.

Several Genes Expressed During Morphogenesis of Lentinus edodes (ImHyup-1)

Differential display of reverse transcription (DDRT)-PCR was conducted to have a profile of the differentially expressed genes during the formation of fruiting body of Lentinus edodes. The lines of L. edodes (ImHyup-1) employed were cultivated in the artificial blocks of sawdust, and the fruiting body was induced from the mycelia or the mass protruded from the brown surface of the sawdust blocks. RNAs were prepared from the four different developmental stages; mycelial, primordial, and stipes and pileus of fruiting body. The fragments of cDNA were synthesized from the combinations of the arbitrary primers and 3' one anchored Oligo-dT primer. Twelve combinations using the primers have been tested, and among them nineteen bands were identified as differentially expressed. Those genes were further analyzed by DNA sequencing and followed by homology search. Characterization of one clone was conducted as a preliminary data and more are under investigation.

Studies on the variation of human serum lipids by intaking lentinus edodes for the preservation of health in rural areas / 日本農村医学会雑誌

For the preservation of health in rural areas, this paper reports on the variation of human serum lipids by intaking lentinus edodes.<BR>Serum lipids levels showed no significant change by intaking lentinus edodes that amounts of 20, 40 and 60g per day each for 5 days. From data of correlationship between serum lipid levels and nutrition intake of experimental diet, it was recognized that high-density-lipoprotein cholesterol level was directly proportional to carbohydrate-fat ratio significantly (p< 0.02), and was inversely proportional to fat intake, fat-protein ratio and carbohydrate-protein ratio significantly (p< 0.05), respectively. Triglycerides level was inversely proportional to protein intake significantly (p< 0.05).<BR>These results concluded that the decrease of serum cholesterol level by intaking of lentinus edodes in healthy young men whose serum cholesterol levels were in normal range was not recognized.