Epithelial-Mesenchymal Interactions for the Development of Intestinal Villi.

Small intestine has a structure called villi that increases the mucosal surface area for nutrient absorption. Intricate and tight epithelial-mesenchymal interactions are required for villi development. These interactions are regulated by signaling molecules, physical forces, and epithelial deformation. Signaling molecules include hedgehog (Hh), bone morphogenetic protein (BMP) and Wnt ligands. The Hh ligand is expressed from the epithelium and binds to the underlying mesenchymal cells, resulting in aggregation into mesenchymal clusters. The clusters express BMP and Wnt ligands to control its size and spacing between clusters. The clusters then form villi. Despite the fact that the villi formation is studied extensively, we do not have a complete understanding. In addition, the recent study shows there is a great relationship between the overexpression of the Hh signal and development of cancer in the gastrointestinal tract. Therefore, signaling between epithelial and mesenchymal cells and their physical interactions will be discussed on this review.

Forkhead Transcription Factor FOXO1 Inhibits Angiogenesis in Gastric Cancer in Relation to SIRT1.

PURPOSE: We previously reported that forkhead transcription factors of the O class 1 (FOXO1) expression in gastric cancer (GC) was associated with angiogenesis-related molecules. However, there is little experimental evidence for the direct role of FOXO1 in GC. In the present study, we investigated the effect of FOXO1 on the tumorigenesis and angiogenesis in GC and its relationship with SIRT1. MATERIALS AND METHODS: Stable GC cell lines (SNU-638 and SNU-601) infected with a lentivirus containing FOXO1 shRNA were established for animal studies as well as cell culture experiments. We used xenograft tumors in nude mice to evaluate the effect of FOXO1 silencing on tumor growth and angiogenesis. In addition, we examined the association between FOXO1 and SIRT1 by immunohistochemical tissue array analysis of 471 human GC specimens and Western blot analysis of xenografted tumor tissues. RESULTS: In cell culture, FOXO1 silencing enhanced hypoxia inducible factor-1α (HIF-1α) expression and GC cell growth under hypoxic conditions, but not under normoxic conditions. The xenograft study showed that FOXO1 downregulation enhanced tumor growth, microvessel areas, HIF-1α activation and vascular endothelial growth factor (VEGF) expression. In addition, inactivated FOXO1 expression was associated with SIRT1 expression in human GC tissues and xenograft tumor tissues. CONCLUSION: Our results indicate that FOXO1 inhibits GC growth and angiogenesis under hypoxic conditions via inactivation of the HIF-1α-VEGF pathway, possibly in association with SIRT1. Thus, development of treatment modalities aiming at this pathway might be useful for treating GC.

Changes in the immunohistochemical localization of the glycine receptor in the superior olivary complex of adult circling mice.

Circling mice is a mutant model of spontaneous deafness exhibiting degenerated spiral ganglion cells in the cochlea and loss of organ of Corti. The balance between glycinergic inhibition and glutamatergic excitation in the lateral superior olive (LSO) is essential for the detection of interaural level differences. Long term weakening of glycinergic synaptic inhibition in the LSO may lead to the downregulation of synaptic release of glycine in dorsal cochlear nucleus and downregulation of postsynaptic glycine receptor (GlyR) activity in the LSO, which may contribute to hearing loss. The present study utilized an immunohistochemical method to assess changes in GlyR immunoreactivity (IR) and the cell number in the superior olivary complex (SOC) of heterozygote (+/cir) and homozygote (cir/cir) circling mice. A significant decrease in the IR was observed in all nuclei of the SOC of homozygous mice. Loss of GlyR immunoreactive cells and a decrement in cell size was also observed in the homozygotes. A decrease in the GlyR IR in the neurons and neuropils, cell number and size of the cir/cir, may lead to profound changes in inhibitory transmission and the functional properties in the SOC nuclei. Therefore, the functional loss of inhibitory neurotransmitters in the brainstem may result in deafness of adult cir/cir mice.

Seroprevalence of Trichinella sp. in Wild Boars (Sus scrofa) from Yanggu-gun, Gangwon-do, Korea.

A total 7 outbreaks of trichinellosis have occurred in Korea, mostly as a result of consumption of raw wild boar (Sus scrofa) meat. Since only 1 serological survey on wild boars had yet been performed in Korea, the present study aimed to estimate the prevalence of trichinellosis in wild boars and some species of rodents by artificial digestion and serological examinations in Yanggu-gun, Gangwon-do, the endemic area of trichinellosis. Both the wild boar and rodent muscle samples revealed no Trichinella larvae by direct examination and artificial digestion method. However, serological examinations revealed that 4 wild boar sera samples out of 118 (3.4%) were positive to Trichinella antigen. Although the recovery of Trichinella larvae ended in a failure, it is proved for the first time that the sylvatic cycle of Trichinella has been maintained in wild boars of Gangwon-do, Korea.

Tissue transglutaminase-interleukin-6 axis facilitates peritoneal tumor spreading and metastasis of human ovarian cancer cells.

Inflammation has recently been implicated in cancer formation and progression. As tissue transglutaminase (TG2) has been associated with both inflammatory signaling and tumor cell behavior, we propose that TG2 may be an important link inducing interleukin-6 (IL-6)-mediated cancer cell aggressiveness, including cancer stem cell-like characteristics and distant hematogenous metastasis. We evaluated the effect of differential TG2 and IL-6 expression on in vivo distant metastasis of human ovarian cancer cells. IL-6 production in human ovarian cancer cells was dependent on their TG2 expression levels. The size and efficiency of tumor sphere formation were correlated with TG2 expression levels and were dependent on TG2-mediated IL-6 secretion in human ovarian cancer cells. Primary tumor growth and propagation in the peritoneum and distant hematogenous metastasis into the liver and lung were also dependent on TG2 and downstream IL-6 expression levels in human ovarian cancer cells. In this report, we provide evidence that TG2 is an important link in IL-6-mediated tumor cell aggressiveness, and that TG2 and downstream IL-6 could be important mediators of distant hematogenous metastasis of human ovarian cancer cells. Intervention specific to TG2 and/or downstream IL-6 in ovarian cancer cells could provide a promising means to control tumor metastasis.

Anatomy of the facial nerve at the condylar area: measurement study and clinical implications.

The aim of this study was to elucidate the detailed anatomy of the facial nerve (FN) at the condylar area to helping physicians preventing the iatrogenic trauma on the nerve. We dissected 25 specimens of the embalmed Korean cadavers (13 males and 2 females; mean age 76.9 years). The FN course at the condylar was examined, and the location of the FN branches was measured with superficial standards. The trunks of the FN emerged in the condylar area as one trunk, two trunks, and a loop or plexiform in 36%, 12%, and 52% areas, respectively. The zygomatic branch (Zbr) of FN passed over the tragus-alar line 23 mm anterior to the tragus (Tg) in most of the cases. The Zbr passed over the vertical line 2 cm anterior to the Tg through the area about 6 to 20 mm inferior to the Tg. Regardless of careful approach techniques to the condylar area, the FN could be damaged by a careless manipulation. Any reference landmarks could not guarantee the safety during the approach to the condylar area because more than half of the cases present the complicated branching type in the front of the Tg.

Overproduction of Laccase by the White-Rot Fungus Pleurotus ostreatus Using Apple Pomace as Inducer.

Laccase activity of Pleurotus ostreatus is significantly increased by the addition of apple pomace. Among various conditions, the best concentration of apple pomace and cultivation time for the production of laccase by P. ostreatus was 2.5% and 9 days, respectively. Reverse transcription polymerase chain reaction analyses of laccase isoenzyme genes, including pox1, pox3, pox4, poxc, poxa3, and poxa1b, revealed a clear effect of apple pomace on transcription induction. Our findings reveal that the use of apple pomace can be a model for the valuable addition of similar wastes and for the development of a solid-state fermenter and commercial production of oyster mushroom P. ostreatus.

Whole genome and global gene expression analyses of the model mushroom Flammulina velutipes reveal a high capacity for lignocellulose degradation.

Flammulina velutipes is a fungus with health and medicinal benefits that has been used for consumption and cultivation in East Asia. F. velutipes is also known to degrade lignocellulose and produce ethanol. The overlapping interests of mushroom production and wood bioconversion make F. velutipes an attractive new model for fungal wood related studies. Here, we present the complete sequence of the F. velutipes genome. This is the first sequenced genome for a commercially produced edible mushroom that also degrades wood. The 35.6-Mb genome contained 12,218 predicted protein-encoding genes and 287 tRNA genes assembled into 11 scaffolds corresponding with the 11 chromosomes of strain KACC42780. The 88.4-kb mitochondrial genome contained 35 genes. Well-developed wood degrading machinery with strong potential for lignin degradation (69 auxiliary activities, formerly FOLymes) and carbohydrate degradation (392 CAZymes), along with 58 alcohol dehydrogenase genes were highly expressed in the mycelium, demonstrating the potential application of this organism to bioethanol production. Thus, the newly uncovered wood degrading capacity and sequential nature of this process in F. velutipes, offer interesting possibilities for more detailed studies on either lignin or (hemi-) cellulose degradation in complex wood substrates. The mutual interest in wood degradation by the mushroom industry and (ligno-)cellulose biomass related industries further increase the significance of F. velutipes as a new model.

Immunomodulating and Antitumor Activities of Panellus serotinus Polysaccharides.

This study was initiated in order to investigate the anticancer and immunomodulating activities of crude polysaccharides extracted in methanol, neutral saline, and hot water (hereinafter referred to as Fr. MeOH, Fr. NaCl, and Fr. HW, respectively) from the fruiting bodies of Panellus serotinus. Content of ß-glucan and protein in Fr. MeOH, Fr. NaCl, and Fr. HW extracts of P. serotinus ranged from 22.92~28.52 g/100 g and 3.24~3.68 g/100 g, respectively. In vitro cytotoxicity tests, none of the various fractions of crude polysaccharides were cytotoxic against sarcoma 180, HT-29, NIH3T3, and RAW 264.7 cell lines at the tested concentration. Intraperitoneal injection with crude polysaccharides resulted in a life prolongation effect of 23.53~44.71% in mice previously inoculated with sarcoma 180. Treatment with Fr. HW resulted in an increase in the numbers of spleen cells by 1.3 fold at the concentration of 50 µg/mL compared with control. Treatment with Fr. NaCl resulted in improvement of the immuno-potentiating activity of B lymphocytes by increasing the alkaline phosphatase activity by 1.4 fold, compared with control, at the concentration of 200 µg/mL. Among the three fractions, maximum nitric oxide (13.48 µM) was recorded at 500 µg/mL in Fr. HW. Production of tumor necrosis factor alpha, interleukin-1ß, and interleukin-6 was significantly higher, compared to the positive control, concanavalin A, at the tested concentration. Therefore, treatment with crude polysaccharides extracted from the fruiting body of P. serotinus could result in improvement of antitumor activity.

Taxonomy of Ganoderma lucidum from Korea Based on rDNA and Partial ß-Tubulin Gene Sequence Analysis.

In the present study, a phylogenetic analysis was undertaken based on the internal transcribed spacer (ITS) rDNA and partial ß-tubulin gene sequence of the Ganoderma species. The size of the ITS rDNA regions from different Ganoderma species varied from 625 to 673 bp, and those of the partial ß-tubulin gene sequence were 419 bp. Based on the results, a phylogenetic tree was prepared which revealed that Korean Ganoderma lucidum strains belong in a single group along with a G. lucidum strain from Bangladesh.

Anticancer and Immunopotentiating Activities of Crude Polysaccharides from Pleurotus nebrodensis on Mouse Sarcoma 180.

Pleurotus nebrodensis is an edible and commercially available mushroom in Korea. This study was conducted in order to evaluate the anticancer and immunopotentiating activities of crude polysaccharides, extracted in methanol, neutral saline, and hot water (hereafter referred to as Fr. MeOH, Fr. NaCl, and Fr. HW, respectively) from the fruiting bodies of P. nebrodensis. ß-Glucan and protein contents in Fr. MeOH, Fr. NaCl, and Fr. HW extracts of P. nebrodensis ranged from 23.79~36.63 g/100 g and 4.45~6.12 g/100 g, respectively. Crude polysaccharides were not cytotoxic against sarcoma 180, HT-29, NIH3T3, and RAW 264.7 cell lines at a range of 10~2,000 µg/mL. Intraperitoneal injection with crude polysaccharides resulted in a life prolongation effect of 11.76~27.06% in mice previously inoculated with sarcoma 180. Treatment with Fr. NaCl resulted in an increase in the numbers of spleen cells by 1.49 fold at the concentration of 50 µg/mL, compared with control. Fr. HW improved the immuno-potentiating activity of B lymphocytes through an increase in alkaline phosphatase activity by 1.65 fold, compared with control at 200 µg/mL. Maximum production of nitric oxide (14.3 µM) was recorded in the Fr. NaCl fraction at 200 µg/mL. Production of tumor necrosis factor-α (TNF-α), interleukin-1ß (IL-1ß), and interleukin-6 (IL-6) was significantly higher, compared to control, and IL-6 production was highest, in contrast to TNF-α, IL-1ß, and positive control, concanavalin at the tested concentration of the various fractions. Results of the current study suggest that polysaccharides extracted from P. nebrodensis have a strong anticancer effect and may be useful as an ingredient of biopharmaceutical products for treatment of cancer.

Comparative genomics of the mating-type loci of the mushroom Flammulina velutipes reveals widespread synteny and recent inversions.

BACKGROUND: Mating-type loci of mushroom fungi contain master regulatory genes that control recognition between compatible nuclei, maintenance of compatible nuclei as heterokaryons, and fruiting body development. Regions near mating-type loci in fungi often show adapted recombination, facilitating the generation of novel mating types and reducing the production of self-compatible mating types. Compared to other fungi, mushroom fungi have complex mating-type systems, showing both loci with redundant function (subloci) and subloci with many alleles. The genomic organization of mating-type loci has been solved in very few mushroom species, which complicates proper interpretation of mating-type evolution and use of those genes in breeding programs. METHODOLOGY/PRINCIPAL FINDINGS: We report a complete genetic structure of the mating-type loci from the tetrapolar, edible mushroom Flammulina velutipes mating type A3B3. Two matB3 subloci, matB3a that contains a unique pheromone and matB3b, were mapped 177 Kb apart on scaffold 1. The matA locus of F. velutipes contains three homeodomain genes distributed over 73 Kb distant matA3a and matA3b subloci. The conserved matA region in Agaricales approaches 350 Kb and contains conserved recombination hotspots showing major rearrangements in F. velutipes and Schizophyllum commune. Important evolutionary differences were indicated; separation of the matA subloci in F. velutipes was diverged from the Coprinopsis cinerea arrangement via two large inversions whereas separation in S. commune emerged through transposition of gene clusters. CONCLUSIONS/SIGNIFICANCE: In our study we determined that the Agaricales have very large scale synteny at matA (∼350 Kb) and that this synteny is maintained even when parts of this region are separated through chromosomal rearrangements. Four conserved recombination hotspots allow reshuffling of large fragments of this region. Next to this, it was revealed that large distance subloci can exist in matB as well. Finally, the genes that were linked to specific mating types will serve as molecular markers in breeding.

Antioxidant and antityrosinase activities of various extracts from the fruiting bodies of Lentinus lepideus.

Lentinus lepideus is an edible mushroom currently available in Korea. The acetone, methanol and hot water extracts were prepared and assayed for their antioxidant and antityrosinase inhibitory activities. The hot water extract showed the strongest ß-carotene-linoleic acid inhibition compared to the other extracts. At 8 mg/mL, the methanolic extract showed a high reducing power of 1.21. The acetone and methanol extracts were more effective in scavenging DPPH radicals than the hot water extract. The strongest chelating effect was obtained from the methanolic extract. Xanthine oxidase and tyrosinase inhibitory activities of the acetonic, methanol and hot water extracts increased with increasing concentration. Gallic acid, chlorogenic acid, vanillin, naringin, naringenin, formononetin, and biochanin-A were detected in the acetonitrile and hydrochloric acid (5:1) solvent extract. This study suggests that fruiting bodies of L. lepideus can potentially be used as a readily accessible source of natural antioxidants.

Assessment of Antioxidant and Phenolic Compound Concentrations as well as Xanthine Oxidase and Tyrosinase Inhibitory Properties of Different Extracts of Pleurotus citrinopileatus Fruiting Bodies.

Cellular damage caused by reactive oxygen species has been implicated in several diseases, thus establishing a significant role for antioxidants in maintaining human health. Acetone, methanol, and hot water extracts of Pleurotus citrinopileatus were evaluated for their antioxidant activities against ß-carotene-linoleic acid and 1,1-diphenyl-2-picrylhydrazyl (DPPH) radicals, reducing power, ferrous ion-chelating abilities, and xanthine oxidase inhibitory activities. In addition, the tyrosinase inhibitory effects and phenolic compound contents of the extracts were also analyzed. Methanol and acetone extracts of P. citrinopileatus showed stronger inhibition of ß-carotene-linoleic acid compared to the hot water extract. Methanol extract (8 mg/mL) showed a significantly high reducing power of 2.92 compared to the other extracts. The hot water extract was more effective than the acetone and methanole extracts for scavenging DPPH radicals. The strongest chelating effect (92.72%) was obtained with 1.0 mg/mL of acetone extract. High performance liquid chromatography analysis detected eight phenolic compounds, including gallic acid, protocatechuic acid, chlorogenic acid, ferulic acid, naringenin, hesperetin, formononetin, and biochanin-A, in an acetonitrile and hydrochloric acid (5 : 1) solvent extract. Xanthine oxidase and tyrosinase inhibitory activities of the acetone, methanol, and hot water extracts increased with increasing concentration. This study suggests that fruiting bodies of P. citrinopileatus can potentially be used as a readily accessible source of natural antioxidants.

Detection of Extracellular Enzyme Activities in Ganoderma neo-japonicum.

The ability of Ganoderma to produce extracellular enzymes, including ß-glucosidase, cellulase, avicelase, pectinase, xylanase, protease, amylase, and ligninase was tested in chromogenic media. ß-glucosidase showed the highest activity, among the eight tested enzymes. In particular, Ganoderma neo-japonicum showed significantly stronger activity for ß-glucosidase than that of the other enzymes. Two Ganoderma lucidum isolates showed moderate activity for avicelase; however, Ganoderma neo-japonicum showed the strongest activity. Moderate ligninase activity was only observed in Ganoderma neo-japonicum. In contrast, pectinase, amylase, protease, and cellulase were not present in Ganoderma. The results show that the degree of activity of the tested enzymes varied depending on the Ganoderma species tested.

Optimal Media Conditions for the Detection of Extracellular Cellulase Activity in Ganoderma neo-japonicum.

To determine the optimal media conditions for the detection of the extracellular cellulase activity in Ganoderma neo-japonicum, we varied three media conditions: dye reagent, pH, and temperature. We evaluated the use of four dyes, Congo red, phenol red, remazol brilliant blue, and trypan blue. To observe the effect of pH on the chromogenic reaction, we tested media ranging from 4.5 to 8.0. To research the effect of temperature on the clear zone and the fungus growing zone, we tested temperatures ranging from 15 to 35℃. On the whole, the best protocol called for Ganoderma neo-japonicum transfer onto media containing Congo red with a pH of 7.0, followed by incubation at 25℃ for 5 days. Our results will be useful to researchers who study extracellular enzyme activity in Ganoderma neo-japonicum.

Appraisal of Antihyperlipidemic Activities of Lentinus lepideus in Hypercholesterolemic Rats.

The wild edible mushroom, Lentinus lepideus has recently been cultivated for commercial use in Korea. While the mushroom has been widely used for nutritional and medicinal purposes, the possible anti-hyperlipidemic action is unclear. The effects of dietary L. lepideus on plasma and feces biochemical and on the liver histological status were investigated in hypercholesterolemic rats. Six-wk-old female Sprague-Dawley albino rats were divided into three groups of 10 rats each. Biochemical and histological examinations were performed. A diet containing 5% L. lepideus fruiting bodies reduced plasma total cholesterol, triglyceride, low-density lipoprotein, total lipid, phospholipids, and the ratio of low-density to high-density lipoprotein. Body weight was reduced. The diet did not adversely affect plasma biochemical and enzyme profiles. L. lepideus reduced significantly plasma ß- and pre-ß-lipoprotein, while α-lipoprotein content was increased. A histological study of hepatic cells by conventional hematoxylin-eosin and oil red O staining revealed normal findings for mushroom-fed hypercholesterolemic rats. The present study suggests that a diet supplemented with L. lepideus can provide health benefits by acting on the atherogenic lipid profile in hypercholesterolemic rats.

Development of Detection Methods for Cellulolytic Activity of Auricularia auricula-judae.

To obtain basic information on the detection of cellulolytic activity in Auricularia auricula-judae, the influences of dye reagent, pH, and temperature were assessed. Chromogenic dye (congo red, phenol red, remazol brilliant blue, and trypan blue) was individually incorporated into a medium containing either carboxymethyl-cellulose, Avicel, or D-cellobiose as a polysaccharide carbon substrate. The other assessments utilized pHs ranging from 4.5 to 8.0 and temperatures from 15~35℃. Overall, when A. auricula-judae species were transferred onto media contained Congo red and adjusted pH 7.0 and then incubated at 25℃ for 5 days, the clear zone indicative of cellulolytic activity was more pronounced.

Culture Conditions for Mycelial Growth of Coriolus versicolor.

Coriolus versicolor, is one of the most popular medicinal mushrooms due its various biologically active components. This study was conducted to obtain basic information regarding the mycelial culture conditions of C. versicolor. Based on the culture, and MCM media were suitable for the mycelial growth of the mushroom. The optimum carbon and nitrogen sources were dextrin and yeast extract, respectively, and the optimum C/N ratio was 10 to 2 when 2% glucose was used. Other minor components required for optimal growth included thiamine-HCl and biotin as vitamins, succinic acid, lactic acid and citric acid as organic acids, as well as MgSO4·7H2O as mineral salts.

Antioxidant Activities and Tyrosinase Inhibitory Effects of Different Extracts from Pleurotus ostreatus Fruiting Bodies.

We evaluated the antioxidant activity and tyrosinase inhibitory effects of Pleurotus ostreatus fruiting bodies extracted with acetone, methanol, and hot water. The antioxidant activities were tested against ß-carotene-linoleic acid, reducing power, 1,1-diphenyl-2-picrylhydrazyl free radical scavenging activity, and ferrous chelating ability. Furthermore, phenolic acid and flavonoid contents were also analyzed. The methanol extract showed the strongest ß-carotene-linoleic acid inhibition as compared to the other exracts. The acetone extract (8 mg/mL) showed a significantly high reducing power of 1.54 than the other extracts. The acetone extract was more effective than other extracts for scavenging on 1,1-diphenyl-2-picrylhydrazyl radicals. The strongest chelating effect (85.66%) was obtained from the acetone extract at 1.0 mg/mL. The antioxidant activities of the extracts from the P. ostreatus fruiting bodies increased with increasing concentration. A high performance liquid chromatography analysis detected seven phenolic compounds, including gallic acid, protocatechuic acid, chlorogenic acid, naringenin, hesperetin, formononetin, and biochanin-A in an acetonitrile and 0.1 N hydrochloric acid (5: 1) solvent extract. The total phenolic compound concentration was 188 µg/g. Tyrosinase inhibition of the acetone, methanol, and hot water P. ostreatus extracts increased with increasing concentration. The results revealed that the methanol extract had good tyrosinase inhibitory ability, whereas the acetone and hot water extracts showed moderate activity at the concentrations tested. The results suggested that P. ostreatus may have potential as a natural antioxidant.