Wing Keung Liu

The immunomodulatory and antitumor activities of lectins from the mushroom Tricholoma mongolicum

TML-1 and TML-2 were two lectins isolated from the mushroom Tricholoma mongolicum. They did not differ appreciably in their pH stability and cationic requirement for hemagglutinating activity. They both stimulated the production of nitrite ions and activated the macrophages in mice. The two lectins were able to inhibit the growth of implanted sarcoma 180 cells by 68.84% and 92.39% respectively. The growth of tumor cells in the mouse peritoneal cavity was also inhibited by the two lectins with TML-2 expressing a greater potency.

Polysaccharide—peptide complexes from the cultured mycelia of the mushroom coriolus versicolor and their culture medium activate mouse lymphocytes and macrophages

The aim of this study was to investigate the effects of the mushroom Coriolus versicolor on cells of the immune system. The cultured mycelia of the mushroom Coriolus versicolor and their culture medium were separately extracted with boiling water. The resulting polysaccharopeptide preparations were designated intramycelial (IM) and extramycelial materials (EM), and were separated by gel filtration before determining their effects on lymphocytes and macrophages in vitro and in vivo. After gel filtration on Sepharose 6B, only a single peak with a molecular weight of 13-19 KDa was obtained. Gel filtration of IM and EM on Sephadex G-50 revealed the presence of a larger peak of 28 KDa (from IM) and 15 KDa (from EM) and a smaller peak of 3.5 KDa. IM, EM and their large molecular peaks enhanced the mitogenic response of T-cells from BALB/c mice in vitro. Splenocytes from C57BL/6 mice pre-treated by force-feeding with IM and EM demonstrated an augmented mitogenic response to Con A. The macrophages of C57BL/6 mice that had been pre-treated with IM or EM showed an enhanced production of nitrite ions. The results indicate that both mouse lymphocytes and macrophages were activated by preparations of polysaccharopeptide from cultured mycelia and culture medium of C. versicolor. However, no direct cytotoxic activity against fibroblasts, hepatoma cells and choriocarcinoma cells could be demonstrated.

Effects of lectins with different carbohydrate-binding specificities on hepatoma, choriocarcinoma, melanoma and osteosarcoma cell lines.

The effects of lectins with different carbohydrate-binding specificities on human hepatoma (H3B), human choriocarcinoma (JAr), mouse melanoma (B16) and rat osteosarcoma (ROS) cell lines were investigated. Cell viability was estimated by uptake of crystal violet. Wheat germ lectin was the lectin with the most deleterious effect on the viability of H3B, JAr and ROS cell lines. The cytotoxicity of lectins with similar sugar-binding specificity to wheat germ lectin, including Maackia amurensis lectin and Solanum tuberosum lectin, was weaker than that of wheat germ lectin. N-acetylgalactosamine-and galactose-binding Tricholoma mongolicum lectin ranked third, after wheat germ lectin and Maackia amurensis lectin, with regard to its effect on H3B, and ranked, together with Maackia amurensis lectin, as the lectins with the second most pronounced effects on ROS. However, the cytotoxic effects of Tricholoma mongolicum lectin on JAr were much weaker than those of Maackia amurensis lectin, Solanum tuberosum lectin and Anguilla anguilla lectin. Artocarpus integrifolia lectin, Lens culinaris lectin and Anguilla anguilla lectin possessed milder cytotoxicity than the remaining lectins. which were approximately equipotent. The mannose-binding Narcissus pseudonarcissus and Lens culinaris lectins were only weakly cytotoxic, the exception being a stronger effect on H3B. The N-acetylgalactosamine-binding Glycine max lectin and methylgalactose-binding Artocarpus integrifolia lectin similarly exhibited low cytotoxicity. It can thus be concluded that in general the ranking was wheat germ lectin > Maackia amurensis lectin approximately Trichloma mongolicum lectins > other aforementioned lectins in cytotoxicity. A particular lectin may manifest more conspicuous toxicity on certain cell lines and less on others.

Activation of peritoneal macrophages by polysaccharopeptide from the mushroom, Coriolus versicolor

Polysaccharopeptide (PSP) is a substance produced by an edible mushroom, Coriolus versicolor which has been claimed to possess antitumor activity. However, neither tumoricidal activity nor cytotoxicity was observed when five tumor cell lines and mouse peritoneal macrophages were cultured in vitro in the presence of 2.5-10 micrograms/ml PSP. An increase in the production of reactive nitrogen intermediates, reactive oxygen intermediates (superoxide anions) and tumor necrosis factor was measured in peritoneal macrophages collected from inbred C57 mice which had received PSP in the drinking water for 2 weeks. Northern blot analysis also demonstrated that PSP activated the transcription of tumor necrosis factor gene in these cells, indicating that PSP exerted an immunomodulatory effect on the defensive cells.

Antiproliferative effect of pineal indoles on cultured tumor cell lines

Abstract: The in vitro antiproliferative action of pineal indoles on several tumor cell lines including melanoma (B16), sarcoma (S180), macrophage‐like cell line (PU5), fibroblasts (3T3), and choriocarcinoma (JAr) was examined by measuring the incorporation of 3H‐thymidine by the tumor cells, and, in the case of melanoma cells, by also measuring the incorporation of 3H‐leucine and 3H‐uridine. Uptake of crystal violet was used to assess the viability of the tumor cells. The order of inhibitory potency of the indoles was found to be methoxytryptamine > melatonin, methoxytryptophol, hydroxytryptophol, and methoxyindoleacetic acid > serotonin and hydroxyindoleactic acid. The possibility of an adverse effect of the indoles on the viability of normal cells was also investigated by employing a primary culture of rat hepatocytes. The release of glutamate‐oxaloacetate transaminase by hepatocytes was not affected by the indoles, although the release of glutamate‐pyruvate transaminase was increased to a small extent and the uptake of crystal violet was slightly inhibited

Immunomodulation and antitumor activity of polysaccharide-protein complex from the culture filtrates of a local edible mushroom, Tricholoma lobayense

1. The polysaccharide-protein complex (PSPC) isolated from the culture filtrate of Tricholoma lobayense showed antitumor activity in mice. 2. PSPC had the ability to restore the phagocytic function of peritoneal exudate cells (PEC) and T-cell mitogenic activity of tumor-bearing mice. 3. An increase in the production of reactive nitrogen intermediates and tumor necrosis factor (TNF) was determined in PEC of mice that had received PSPC. 4. The present study showed that PSPC both induced the various immune responses in vivo and exhibited cytotoxicity against tumor cell lines in the presence of PSPC at doses of 30 and 60 micrograms/ml in vitro.

Action of α-momorcharin, a ribosome inactivating protein, on cultured tumor cell lines

Abstract 1. 1. α-Momorcharin, a glycoprotein isolated from seeds of the bitter gourd, Momordica charantia inhibited incorporation of [3H]thymidine, [3H]leucine and [3H]uridine into P388 (mouse monocyte-macrophage), J774 (Balb/c macrophage), JAR (human placental choriocarcinoma) and sarcoma

Stimulation of murine splenocytes by melatonin and methoxytryptamine

180 cell lines. 2. 2. The most potent inhibitory effect was exerted on P388 cells and the smallest effect on sarcoma cells. 3. 3. α-Momorcharin also enhanced the tumoricidal effect of mouse macrophages on mouse mastocytomal (P815) cells.

Protective roles of Cordyceps on lung fibrosis in cellular and rat models

Male C 57 mice kept under a 14∶10 (L∶D) photoperiod received vehicle (VEH), melatonin (MEL) and methoxytryptamine (MTA) in the drinking water for 2 weeks. Splenocytes from MEL-treated mice showed an augmented mitogenic response to concanavalin A and lipopolysaccharide (LPS) while splenocytes from MTA-treated mice demonstrated an enhanced mitogenic response to LPS when compared to the VEH-treated control. Splenocytes from MEL-treated and MTA-treated mice also produced higher levels of gamma interferon and interleukin-2. Lymphokines prepared from splenocytes of MEL-treated mice stimulated peritoneal macrophages to produce more nitrite than those from splenocytes of MTA-treated and control mice, suggesting that MEL had a stronger stimulating effect on the lymphocytes than MTA. Understimulation of lymphokines from MEL-treated mice, peritoneal macrophages from MTA-treated mice produced a greater inhibition of the growth of murine mastocytoma P 815 cells than that produced by macrophages from control and MEL-treated mice, suggesting that MTA was more potent than MEL in rendering the macrophages responsive to lymphokines. The results point to immunostimulatory actions of the pineal indoles MEL and MTA.

Bioactive proteins and peptides isolated from Chinese medicines with pharmaceutical potential

Abstract Ethnopharmacological relevance Cordyceps sinensis is a fungus used in traditional Chinese medicine as a tonic to soothe the lung for the treatment of fatigue and respiratory diseases. Idiopathic pulmonary fibrosis is a chronic, irreversible and debilitating lung disease showing fibroblast/myofibroblast expansion and excessive deposition of extracellular matrix in the interstitium leading to breathing difficulty. Our previous observation revealed a partial relief of lung fibrosis in patients suffering from severe acute respiratory syndrome (SARS). We hypothesize that Cordyceps has beneficial effects on lung fibrosis and the objective of this study is to explore the target(s) of Cordyceps in the relief of lung fibrosis in animal and cell models and to gain insight into its underlying mechanisms. Material and methods A rat model of bleomycin (BLM)-induced lung fibrosis and a fibrotic cell model with transforming growth factor beta-1 induction were employed in the studies. Results Reduction of infiltration of inflammatory cells, deposition of fibroblastic loci and collagen, formation of reactive oxygen species, and production of cytokines, as well as recovery from imbalance of MMP-9/TIMP-1, were observed in fibrotic rats after treatment with Cordyceps in preventive (from the day of BLM administration) and therapeutic (from 14 days after BLM) regimens. In a fibrotic cell model with transforming growth factor beta-1 induction, the human lung epithelial A549 acquired a mesenchymal phenotype and an increase of vimentin expression with a concomitant decrease of E-cadherin. This epithelial–mesenchymal transition could be partially reverted by cordycepin, a major component of Cordyceps. Conclusion The findings provide an insight into the preventive and therapeutic potentials of Cordyceps for the treatment of lung fibrosis.