Inhibition of decrease in natural killer cell activity in repeatedly restraint-stressed mice by a biological response modifier derived from cultured mycelia of the basidiomycete Tricholoma matsutake

Insights into health promoting effects and myochemical profiles of pine mushroom Tricholoma matsutake

Tricholoma matsutake (TM) is a valuable edible mushroom that has attracted increasing attention due to its potential medicinal values and functional uses. However, the chemical composition and molecular mechanisms behinds TM are not specifically summarized yet. Hence, this review aims to systematically analyze the research progress on the characterization of chemical compositions and the reported health effects of TM in the last 20 years. The myochemical profiles of TM consist of proteins with amino acids, fatty acids, nucleic acids with their derivatives, polysaccharides, minerals, volatile components, phenolic compounds, and steroids. The bioactive substances in TM exert their health effects mainly by regulating body immunity and restoring the balance of the redox system. NF-κB signaling pathway and its downstream cytokines such as TNF-α and IL-6 are the key molecular mechanisms. In addition, MAPK, PI3K-Akt, and JAK-STAT are also involved. NF-κB, MAPK, and PI3K-Akt are also highly related to cancer regulation and thus TM has great anticancer potential. Considering that most studies have only investigated the dosage and inhibition rate of TM on cancer cell lines, more extensive studies need to focus on the specific molecular mechanisms behind these anticancer effects in the future.

Serum pattern profiling for analyzing different types of stress by protein chip technology: a preliminary study

ProteinChip is a widely accepted tool for exploring serum pattern profile to evaluate the risk of somatic diseases from different stressors. In this study, by using surface-enhanced laser desorption/ionization time-of-flight mass spectrometry (SELDI-ToF), the serum proteome from mice under restraint and thermal stresses were profiled in detail and compared with the control group. Around 150 characteristic peaks were detected in all three groups, with m/z ranging from 1500 to 50,000, with most peaks being within the 2000 m/z to 20,000 m/z range. Compared with the control group, three significant protein peaks with m/z values of 2780, 3303 and 3450 appeared specifically in the restrained stress group and four other peaks with m/z values of 7500, 7811, 29,950 and 38,565 in the thermal stress group. Unexpectedly, no universal positive stress peaks were detected. These preliminary results clearly suggested that there might not be a common mechanism shared by various psychophysiological disorders under different stressors. By fast serum proteomics profiling, SELDI-ToF may be a convenient tool for evaluating the risk of stress-induced illness.

Absorption and tissue distribution of an immunomodulatory alpha-D-glucan after oral administration of Tricholoma matsutake

Alpha-D-glucan (MPG-1) separated from Tricholoma matsutake (CM6271) has been reported to show immunomodulatory activities. In this study, the plasma concentration and tissue distribution of MPG-1 after CM6271 oral administration were investigated as part of the action mechanism analysis. When CM6271 was orally administered in a single dose to mice, MPG-1 was absorbed via the intestinal tract, appeared in plasma after 16 h, was gradually excreted from the blood, and fell to background level after 48 h. The time course analysis of MPG-1 in plasma showed the following pharmacokinetic parameters of MPG-1: tmax = 24 h; Cmax = 161.1 ng/mL; AUC(0-infinity) = 2559.7 ng x h/mL. Moreover, MPG-1 was confirmed to localize in Peyer's patches, mesenteric lymph nodes (MLN), and the spleen and to promote IL-12 p70 production and NK cell activity. These results suggest that MPG-1 stimulated the intestinal immune system through Peyer's patches; moreover, it was taken into the blood and stimulated the systemic immune system.

The immunobiology of mushrooms

There has been enormous interest in the biologic activity of mushrooms and innumerable claims have been made that mushrooms have beneficial effects on immune function with subsequent implications for inhibition of tumor growth. The majority of these observations are anecdotal and often lack standardization. However, there remains considerable data on both in vitro and in vivo effects that reflect on the potential of mushroom compounds to influence human immunity. A number of these effects are beneficial but, unfortunately, many responses are still characterized based on phenomenology and there is more speculation than substance. With respect to tumor biology, although many neoplastic lesions are immunogenic, tumor antigens frequently are self antigens and induce tolerance and many patients with cancer exhibit suppressed immune responses, including defective antigen presentation. Therefore, if and when mushroom extracts are effective, they more likely function as a result of improved antigen presentation by dendritic cells than by a direct cytopathic effect. In this review we attempt to place these data in perspective, with a particular focus on dendritic cell populations and the ability of mushroom extracts to modulate immunity. There is, at present, no scientific basis for the use of either mushrooms or mushroom extracts in the treatment of human patients but there is significant potential for rigorous research to understand the potential of mushrooms in human disease and thence to focus on appropriate clinical trials to demonstrate effectiveness and/ or potential toxicity.

Effects of restraint stress on iron, zinc, calcium, and magnesium whole blood levels in mice

OBJECTIVE

Study the effects of acute and chronic restraint stress on the whole blood concentrations of iron (Fe), zinc (Zn), calcium (Ca), and magnesium (Mg) in mice.

MATERIALS AND METHODS

Single or repeat restraints were applied to mice to induce acute or chronic stress. The levels of elements in whole blood were determined by flame atomic absorption spectrometry.

RESULTS

The levels of Fe, Zn, Ca, and Mg in blood in the acute-stress group were 351, 5.05, 60, and 44 microg/ml, respectively, and those in the corresponding control group were 391, 5.90, 59, and 45 microg/ml, respectively. The levels of blood Fe, Zn, Ca, and Mg in the chronic-stress group were 291, 3.62, 59, and 40 microg/ml, respectively, and those in the corresponding control group were 393, 4.82, 48, and 43 microg/ml, respectively. The levels of Fe and Zn in the blood of both the acute-stress and the chronic-stress groups were significantly lower (P < 0.05) than that in the control groups. The Ca level in whole blood was significantly (P < 0.05) higher in the chronic-stress group than that in the control group.

CONCLUSION

Acute and chronic restraint stress can cause changes in blood levels of Fe and Zn in mice.

Development of an enzyme-linked immunosorbent assay to detect an immunomodulatory alpha-D-glucan-protein complex, MPG-1, in basidiomycete Tricholoma matsutake and related processed foods

We previously isolated a novel immunomodulatory alpha-(1,4)(1,6)(1,2)- d-glucan-protein complex (MPG-1) from mycelia of Tricholoma matsutake in basidiomycetes. In the present study, we raised a polyclonal antibody by immunizing rabbits with MPG-1 and constructed a sandwich enzyme-linked immunosorbent assay (ELISA) system to examine the distribution of MPG-1 among edible mushrooms and related processed foods. The system detected MPG-1 quantitatively at concentrations of more than 10 ng/mL, with a coefficient of variation of less than 10% by intra-assay and interassay precision. Analysis with the system of chemically modified MPG-1 suggested that the sugar moiety was mainly involved in the detection. The system detected MPG-1 in the extracts of the fruiting bodies of T. matsutake but not in those of 34 other basidiomycete species. Moreover, a significant amount of MPG-1 was detected in the extracts of their cultured mycelia. The antigenic structure of MPG-1 was relatively stable in terms of pH and temperature. MPG-1 was detected in processed foods supplemented with T. matsutake. These results suggest that MPG-1 is distributed predominantly in T. matsutake species and that the ELISA system can detect it in processed foods supplemented with T. matsutake.

Serum proteomic profiling associated with immune system impaired by stress using ProteinChip technology

We set out to use proteomic profiling as a means of defining serum peptides that are indicative of a stress response related to an impact on the immune system. Two types of mouse models with the immune response impaired under stress (restraint stress and thermal stress) comprised the stressed groups (n = 10 in each group), while mice without stress represented the control group (n = 10). ProteinChip technology (surface-enhanced laser desorption/ionization time-of-flight mass spectrometry) was used to investigate the serum proteomic profiles. Histopathological examination of spleens from the stressed and control groups was performed to select appropriate individuals. Compared with the spleens of normal mice, those of mice subjected to restraint and thermal stress had decreased white pulp and lymphoid nodules, and their distribution and structure changed irregularly. Pathological changes occurred in all individuals in both stressed groups. The m/z values of the protein peaks ranged from 1,500 to 50,000 daltons and were mainly in the 2,000- to 20,000-dalton range. One hundred and fifty protein peaks were detected in the three groups. Four downregulated universal stress protein peaks with m/z of 4,389, 5,341, 5,526, and 6,252 were finally selected. Unexpectedly, no upregulated universal stress protein peaks were detected. These results suggested that impairment of the immune system results from inhibition of growth-promoting factors associated with the immune system. Identified protein peaks may be biomarkers of the impaired immune system under stress.

Isolation and characterization of a novel immunomodulatory alpha-glucan-protein complex from the mycelium of Tricholoma matsutake in basidiomycetes

Tricholoma matsutake, a high-class edible mushroom in Japan, has been reported to have excellent biological activities, but difficulty in cultivating the fruit bodies and limited bulk availability have restricted detailed studies. We have developed a method of culturing in tanks, enabling the bulk supply of the mycelia. The preparation (CM6271) exerts modulative effects on the immune competence of mice and rats. In this study, a sodium hydroxide extract of CM6271 was defatted followed by fractionation with a combination of ion exchange chromatography and gel filtration in order to identify the components involved in the expression of the activity, and a single peak fraction (MPG-1) was obtained with reversed phase chromatography. MPG-1 was a glycoprotein (sugar:protein ratio, 94.3:5.7) with a relative molecular mass of 360 kDa, and the sugar moiety contained about 90% glucose. NMR spectra and methylation analysis revealed that the alpha-1,4-linkage was the predominant glucan linkage with alpha-1,6- and alpha-1,2-linkages in the minority. The amino acid composition in the protein moiety was rich in glutamine, alanine, asparagine, leucine, glycine, valine, serine, threonine, isoleucine, and proline. MPG-1 was resistant to degradation with amylase or protease. The oral administration of MPG-1 promoted, in a dose-dependent manner, the recovery of the mouse natural killer cell activity and serum IL-12 level that had been reduced by the loading of restraint stress. The dose of MPG-1 (25 mg/kg) required for the expression of the effect decreases to 1/12 of that of CM6271 (300 mg/kg). Furthermore, MPG-1 formed a complex with TGF-beta1 in vitro, modulating the biological activity of TGF-beta1 by binding to its active form. These results indicate that the mycelium of T. matsutake contains a novel alpha-glucan-protein complex with immunomodulatory activities.