Histone demethylase KDM2A is a selective vulnerability of cancers relying on alternative telomere maintenance.

Telomere length maintenance is essential for cellular immortalization and tumorigenesis. 5% - 10% of human cancers rely on a recombination-based mechanism termed alternative lengthening of telomeres (ALT) to sustain their replicative immortality, yet there are currently no targeted therapies. Through CRISPR/Cas9-based genetic screens in an ALT-immortalized isogenic cellular model, here we identify histone lysine demethylase KDM2A as a molecular vulnerability selectively for cells contingent on ALT-dependent telomere maintenance. Mechanistically, we demonstrate that KDM2A is required for dissolution of the ALT-specific telomere clusters following recombination-directed telomere DNA synthesis. We show that KDM2A promotes de-clustering of ALT multitelomeres through facilitating isopeptidase SENP6-mediated SUMO deconjugation at telomeres. Inactivation of KDM2A or SENP6 impairs post-recombination telomere de-SUMOylation and thus dissolution of ALT telomere clusters, leading to gross chromosome missegregation and mitotic cell death. These findings together establish KDM2A as a selective molecular vulnerability and a promising drug target for ALT-dependent cancers.

Histone demethylase KDM2A is a selective vulnerability of cancers relying on alternative telomere maintenance.

Telomere length maintenance is essential for cellular immortalization and tumorigenesis. 5% - 10% of human cancers rely on a recombination-based mechanism termed alternative lengthening of telomeres (ALT) to sustain their replicative immortality, yet there are currently no targeted therapies. Through CRISPR/Cas9-based genetic screens in an ALT-immortalized isogenic cellular model, here we identify histone lysine demethylase KDM2A as a molecular vulnerability selectively for cells contingent on ALT-dependent telomere maintenance. Mechanistically, we demonstrate that KDM2A is required for dissolution of the ALT-specific telomere clusters following homology-directed telomere DNA synthesis. We show that KDM2A promotes de-clustering of ALT multitelomeres through facilitating isopeptidase SENP6-mediated SUMO deconjugation at telomeres. Inactivation of KDM2A or SENP6 impairs post-recombination telomere de-SUMOylation and thus dissolution of ALT telomere clusters, leading to gross chromosome missegregation and mitotic cell death. These findings together establish KDM2A as a selective molecular vulnerability and a promising drug target for ALT-dependent cancers.

A FOXO1-dependent transcription network is a targetable vulnerability of mantle cell lymphomas.

Targeting lineage-defined transcriptional dependencies has emerged as an effective therapeutic strategy in cancer treatment. Through screening for molecular vulnerabilities of mantle cell lymphoma (MCL), we identified a set of transcription factors (TFs) including FOXO1, EBF1, PAX5, and IRF4 that are essential for MCL propagation. Integrated chromatin immunoprecipitation and sequencing (ChIP-Seq) with transcriptional network reconstruction analysis revealed FOXO1 as a master regulator that acts upstream in the regulatory TF hierarchy. FOXO1 is both necessary and sufficient to drive MCL lineage commitment through supporting the lineage-specific transcription programs. We further show that FOXO1, but not its close paralog FOXO3, can reprogram myeloid leukemia cells and induce B-lineage gene expression. Finally, we demonstrate that cpd10, a small molecule identified from an enriched FOXO1 inhibitor library, induces a robust cytotoxic response in MCL cells in vitro and suppresses MCL progression in vivo. Our findings establish FOXO1 inhibition as a therapeutic strategy targeting lineage-driven transcriptional addiction in MCL.

Therapy-Induced Transdifferentiation Promotes Glioma Growth Independent of EGFR Signaling.

EGFR is frequently amplified, mutated, and overexpressed in malignant gliomas. Yet the EGFR-targeted therapies have thus far produced only marginal clinical responses, and the underlying mechanism remains poorly understood. Using an inducible oncogenic EGFR-driven glioma mouse model system, our current study reveals that a small population of glioma cells can evade therapy-initiated apoptosis and potentiate relapse development by adopting a mesenchymal-like phenotypic state that no longer depends on oncogenic EGFR signaling. Transcriptome analyses of proximal and distal treatment responses identified TGFß/YAP/Slug signaling cascade activation as a major regulatory mechanism that promotes therapy-induced glioma mesenchymal lineage transdifferentiation. Following anti-EGFR treatment, TGFß secreted from stressed glioma cells acted to promote YAP nuclear translocation that stimulated upregulation of the pro-mesenchymal transcriptional factor SLUG and subsequent glioma lineage transdifferentiation toward a stable therapy-refractory state. Blockade of this adaptive response through suppression of TGFß-mediated YAP activation significantly delayed anti-EGFR relapse and prolonged animal survival. Together, our findings shed new insight into EGFR-targeted therapy resistance and suggest that combinatorial therapies of targeting both EGFR and mechanisms underlying glioma lineage transdifferentiation could ultimately lead to deeper and more durable responses. SIGNIFICANCE: This study demonstrates that molecular reprogramming and lineage transdifferentiation underlie anti-EGFR therapy resistance and are clinically relevant to the development of new combinatorial targeting strategies against malignant gliomas with aberrant EGFR signaling.

Salicibibacter halophilus sp. nov., a moderately halophilic bacterium isolated from kimchi.

A Gram-stain-positive, rod-shaped, alkalitolerant, and halophilic bacterium-designated as strain NKC3-5T-was isolated from kimchi that was collected from the Geumsan area in the Republic of Korea. Cells of isolated strain NKC3-5T were 0.5-0.7 µm wide and 1.4-2.8 µm long. The strain NKC3-5T could grow at up to 20.0% (w/v) NaCl (optimum 10%), pH 6.5-10.0 (optimum pH 9.0), and 25-40°C (optimum 35°C). The cells were able to reduce nitrate under aerobic conditions, which is the first report in the genus Salicibibacter. The genome size and genomic G + C content of strain NKC3-5T were 3,754,174 bp and 45.9 mol%, respectively; it contained 3,630 coding sequences, 16S rRNA genes (six 16S, five 5S, and five 23S), and 59 tRNA genes. Phylogenetic analysis based on 16S rRNA showed that strain NKC3-5T clustered with bacterium Salicibibacter kimchii NKC1-1T, with a similarity of 96.2-97.6%, but formed a distinct branch with other published species of the family Bacillaceae. In addition, OrthoANI value between strain NKC3-5T and Salicibibacter kimchii NKC1-1T was far lower than the species demarcation threshold. Using functional genome annotation, the result found that carbohydrate, amino acid, and vitamin metabolism related genes were highly distributed in the genome of strain NKC3-5T. Comparative genomic analysis revealed that strain NKC3-5T had 716 pan-genome orthologous groups (POGs), dominated with carbohydrate metabolism. Phylogenomic analysis based on the concatenated core POGs revealed that strain NKC3-5T was closely related to Salicibibacter kimchii. The predominant polar lipids were phosphatidylglycerol and two unidentified lipids. Anteiso-C15:0, iso-C17:0, anteiso-C17:0, and iso-C15:0 were the major cellular fatty acids, and menaquinone-7 was the major isoprenoid quinone present in strain NKC3-5T. Cell wall peptidoglycan analysis of strain NKC3-5T showed that meso-diaminopimelic acid was the diagnostic diamino acid. The phephenotypic, genomic, phylogenetic, and chemotaxonomic properties reveal that the strain represents a novel species of the genus Salicibibacter, for which the name Salicibibacter halophilus sp. nov. is proposed, with the type strain NKC3-5T (= KACC 21230T = JCM 33437T).

Allium hookeri Root Extract Inhibits Adipogenesis by Promoting Lipolysis in High Fat Diet-Induced Obese Mice.

Allium hookeri (AH) is widely consumed as a herbal medicine. It possesses biological activity against metabolic diseases. The objective of this study was to investigate effects of AH root water extract (AHR) on adipogenesis in 3T3-L1 cells and in high-fat diet (HFD)-induced obese mice. AHR inhibited lipid accumulation during adipocyte differentiation by downregulation of gene expression, such as hormone sensitive lipase (HSL), lipoprotein lipase (LPL) and an adipogenic gene, CCAAT/enhancer binding protein-α in 3T3-L1 preadipocytes. Oral administration of AHR significantly suppressed body weight gain, adipose tissue weight, serum leptin levels, and adipocyte cell size in HFD-induced obese mice. Moreover, AHR significantly decreased hepatic mRNA expression levels of cholesterol synthesis genes, such as 3-hydroxy-3-methylglutaryl CoA reductase, sterol regulatory element-binding transcription factor (SREBP)-2, and low-density lipoprotein receptor, as well as fatty acid synthesis genes, such as SREBP-1c and fatty acid synthase. Serum triglyceride levels were also lowered by AHR, likely as a result of the upregulating gene involved in fatty acid ß-oxidation, carnitine palmitoyltransferase 1a, in the liver. AHR treatment activated gene expression of peroxisome proliferator-activated receptor-γ, which might have promoted HSL and LPL-medicated lipolysis, thereby reducing white adipose tissue weight. In conclusion, AHR treatment can improve metabolic alterations induced by HFD in mice by modifying expression levels of genes involved in adipogenesis, lipogenesis, and lipolysis in the white adipose tissue and liver.

Human Placenta Hydrolysate Promotes Liver Regeneration via Activation of the Cytokine/Growth Factor-Mediated Pathway and Anti-oxidative Effect.

Liver regeneration is a very complex process and is regulated by several cytokines and growth factors. It is also known that liver transplantation and the regeneration process cause massive oxidative stress, which interferes with liver regeneration. The placenta is known to contain various physiologically active ingredients such as cytokines, growth factors, and amino acids. In particular, human placenta hydrolysate (hPH) has been found to contain many amino acids. Most of the growth factors found in the placenta are known to be closely related to liver regeneration. Therefore, in this study, we investigated whether hPH is effective in promoting liver regeneration in rats undergoing partial hepatectomy. We confirmed that cell proliferation was significantly increased in HepG2 and human primary cells. Hepatocyte proliferation was also promoted in partial hepatectomized rats by hPH treatment. hPH increased liver regeneration rate, double nucleic cell ratio, mitotic cell ratio, proliferating cell nuclear antigen (PCNA), and Ki-67 positive cells in vivo as well as interleukin (IL)-6, tumor necrosis factor alpha (TNF-α), and hepatocyte growth factor (HGF). Moreover, Kupffer cells secreting IL-6 and TNF-α were activated by hPH treatment. In addition, hPH reduced thiobarbituric acid reactive substances (TBARs) and significantly increased glutathione (GSH), glutathione peroxidase (GPx), and superoxide dismutase (SOD). Taken together, these results suggest that hPH promotes liver regeneration by activating cytokines and growth factors associated with liver regeneration and eliminating oxidative stress.

Rotavirus-mediated alteration of gut microbiota and its correlation with physiological characteristics in neonatal calves.

Diarrhea is a fatal disease to neonatal calves, and rotavirus is the main pathogen associated with neonatal calf diarrhea. Although previous studies have reported that the gut microbiota is changed in calves during diarrhea, less is known about whether rotavirus infection alters the structure of the gut microbiota. Here, we characterized fecal microbial communities and identified possible relationships between the gut microbiota profiles and physiological parameters. Five fecal specimens of rotavirus-infected calves from 1 to 30 days after birth and five fecal specimens of age-matched healthy calves were used for the microbial community analysis using the Illumina MiSeq sequencer. Rotavirus infection was associated with reduced rotavirus infection significantly reduced the richness and diversity of the bacterial community. Weighted unique fraction metric analysis exhibited significant differences in community membership and structure between healthy and rotavirus-infected calves. Based on relative abundance analysis and linear discriminant analysis effect size, we found that the representative genera from Lactobacillus, Subdoligranulum, Blautia, and Bacteroides were closely related to healthy calves, while the genera Escherichia and Clostridium were closely affiliated to rotavirus-infected calves. Furthermore, canonical correlation analysis and Pearson correlation coefficient results revealed that the increased relative abundances of Lactobacillus, Subdoligranulum, and Bacteroides were correlated with normal levels of physiological characteristics such as white blood cells, blood urea nitrogen, serum amyloid protein A, and glucose concentration in serum. These results suggest that rotavirus infection alters the structure of the gut microbiota, correlating changes in physiological parameters. This study provides new information on the relationship between gut microbiota and the physiological parameters of rotavirus-mediated diarrheic calves.

Salicibibacter kimchii gen. nov., sp. nov., a moderately halophilic and alkalitolerant bacterium in the family Bacillaceae, isolated from kimchi.

A moderately halophilic and alkalitolerant bacterial strain NKC1-1T was isolated from commercial kimchi in Korea. Strain NKC1-1T was Gram-stain-positive, aerobic, rod-shaped, non-motile, and contained diaminopimelic acid-type murein. Cell growth was observed in a medium containing 0-25% (w/v) NaCl (optimal at 10% [w/v]), at 20-40°C (optimal at 37°C) and pH 6.5-10.0 (optimal at pH 9.0). The major isoprenoid quinone of the isolate was menaquinone-7, and the major polar lipids were phosphatidylglycerol and unidentified phospholipids. Cell membrane of the strain contained iso-C17:0 and anteiso-C15:0 as the major fatty acids. Its DNA G + C content was 45.2 mol%. Phylogenetic analysis indicated the strain to be most closely related to Geomicrobium halophilum with 92.7-92.9% 16S rRNA gene sequence similarity. Based on polyphasic taxonomic evaluation with phenotypic, phylogenetic, and chemotaxonomic analyses, the strain represents a novel species in a new genus, for which the name Salicibibacter kimchii gen. nov., sp. nov. is proposed (= CECT 9537T; KCCM 43276T).

Mixture of Two Lactobacillus plantarum Strains Modulates the Gut Microbiota Structure and Regulatory T Cell Response in Diet-Induced Obese Mice.

SCOPE: The gut microbiota has been linked to diet-induced obesity, and microorganisms that influence obesity have important health implications. In this study, the anti-obesity effects of two Lactobacillus plantarum strains (DSR M2 and DSR 920) isolated from kimchi are investigated. METHODS AND RESULTS: Mice are fed a normal or high-fat diet with or without DSR M2 and DSR 920 (DSR, 1 × 109 CFU d-1 ) for 12 weeks. DSR improves the obesity state, as evidenced by the i) suppressed obesity-related markers, e.g., gains in body weight and fat mass, ii) reduced serum and liver triglyceride levels, iii) upregulated ß-oxidation and downregulated lipogenesis-related genes in the liver, iv) reduced serum leptin levels, v) altered microbial communities, vi) increased regulatory T cell immunity, and vii) suppressed inflammatory response. In addition, correlation analysis shows that Akkermansia muciniphila and the genus Anaerostipes, which are increased in the DSR group, are negatively correlated with obesity-related markers, but Mucispirillum schaedleri, which is increased in the high-fat-diet (HFD) group, is positively correlated with serum leptin level. CONCLUSION: Lactobacillus plantarum DSR M2 and DSR 920 are candidate probiotics for the prevention and amelioration of obesity.

Lactobacillus sakei WIKIM30 Ameliorates Atopic Dermatitis-Like Skin Lesions by Inducing Regulatory T Cells and Altering Gut Microbiota Structure in Mice.

Lactobacillus sakei WIKIM30 is a Gram-positive facultative anaerobic bacterium isolated from kimchi, a Korean fermented vegetable food. In this study, we found that WIKIM30 promoted regulatory T cell (Treg) differentiation by inducing dendritic cells with tolerogenic properties. The production of the T helper (Th) 2-associated cytokine interleukin (IL)-4 was decreased, but that of the Treg-associated cytokine IL-10 was increased in splenocytes from ovalbumin-sensitized mice treated with WIKIM30. We also investigated the inhibitory capacity of WIKIM30 on the development of 2,4-dinitrochlorobenzene-induced atopic dermatitis (AD), a Th2-dominant allergic disease in mice. Oral administration of L. sakei WIKIM30 significantly reduced AD-like skin lesions and serum immunoglobulin E and IL-4 levels while decreasing the number of CD4+ T cells and B cells and the levels of Th2 cytokines (IL-4, IL-5, and IL-13) in peripheral lymph nodes and enhancing Treg differentiation and IL-10 secretion in mesenteric lymph nodes. In addition, WIKIM30 modulated gut microbiome profiles that were altered in AD mice, which showed increases in Arthromitus and Ralstonia and a decrease in Ruminococcus abundance. These changes were reversed by WIKIM30 treatment. Notably, the increase in Ruminococcus was highly correlated with Treg-related responses and may contribute to the alleviation of AD responses. Together, these results suggest that oral administration of L. sakei WIKIM30 modulates allergic Th2 responses enhancing Treg generation and increases the relative abundance of intestinal bacteria that are positively related to Treg generation, and therefore has therapeutic potential for the treatment of AD.

NABi, a novel ß-sheet breaker, inhibits Aß aggregation and neuronal toxicity: Therapeutic implications for Alzheimer's disease.

Amyloid beta (Aß) aggregates are an important therapeutic target for Alzheimer's disease (AD), a fatal neurodegenerative disease. To date, AD still remains a big challenge due to no effective treatments. Based on the property that Aß aggregates have the cross-ß-structure, a common structural feature in amyloids, we systemically designed the Aß-aggregation inhibitor that maintains Aß-interacting ability but removes toxic part from SOD1 (superoxide dismutase 1)-G93A. We identified NABi (Natural Aß Binder and Aß-aggregation inhibitor) composed of ß2-3 strands, a novel breaker of Aß aggregation, which does not self-aggregate and has no cytotoxicity at all. The NABi blocks Aß-fibril formation in vitro and in vivo and prevents neuronal cell death, a hallmark of AD pathogenesis. Such anti-amyloidogenic properties can provide novel strategies for treating AD. Furthermore, our study provides molecular insights into the design of amyloidogenic inhibitors to cure various neurodegenerative and amyloid-associated diseases, as NABi would regulate aggregation of other toxic ß-sheet proteins other than Aß.

Cold atmospheric plasma (CAP), a novel physicochemical source, induces neural differentiation through cross-talk between the specific RONS cascade and Trk/Ras/ERK signaling pathway.

Plasma, formed by ionization of gas molecules or atoms, is the most abundant form of matter and consists of highly reactive physicochemical species. In the physics and chemistry fields, plasma has been extensively studied; however, the exact action mechanisms of plasma on biological systems, including cells and humans, are not well known. Recent evidence suggests that cold atmospheric plasma (CAP), which refers to plasma used in the biomedical field, may regulate diverse cellular processes, including neural differentiation. However, the mechanism by which these physicochemical signals, elicited by reactive oxygen and nitrogen species (RONS), are transmitted to biological system remains elusive. In this study, we elucidated the physicochemical and biological (PCB) connection between the CAP cascade and Trk/Ras/ERK signaling pathway, which resulted in neural differentiation. Excited atomic oxygen in the plasma phase led to the formation of RONS in the PCB network, which then interacted with reactive atoms in the extracellular liquid phase to form nitric oxide (NO). Production of large amounts of superoxide radical (O2-) in the mitochondria of cells exposed to CAP demonstrated that extracellular NO induced the reversible inhibition of mitochondrial complex IV. We also demonstrated that cytosolic hydrogen peroxide, formed by O2- dismutation, act as an intracellular messenger to specifically activate the Trk/Ras/ERK signaling pathway. This study is the first to elucidate the mechanism linking physicochemical signals from the CAP cascade to the intracellular neural differentiation signaling pathway, providing physical, chemical and biological insights into the development of therapeutic techniques to treat neurological diseases.

Virgibacillus kimchii sp. nov., a halophilic bacterium isolated from kimchi.

A Gram-stain-positive, halophilic, rod-shaped, non-motile, spore forming bacterium, strain NKC1-2T, was isolated from kimchi, a Korean fermented food. Comparative analysis based on 16S rRNA gene sequence demonstrated that the isolated strain was a species of the genus Virgibacillus. Strain NKC1-2T exhibited high level of 16S rRNA gene sequence similarity with the type strains of Virgibacillus xinjiangensis SL6-1T (96.9%), V. sediminis YIM kkny3T (96.8%), and V. salarius SA-Vb1T (96.7%). The isolate grew at pH 6.5-10.0 (optimum, pH 8.5-9.0), 0.0-25.0% (w/v) NaCl (optimum, 10-15% NaCl), and 15-50°C (optimum, 37°C). The major menaquinone in the strain was menaquinone-7, and the main peptidoglycan of the strain was meso-diaminopimelic acid. The predominant fatty acids of the strain were iso-C14:0, anteisio-C15:0, iso- C15:0, and iso-C16:0 (other components were < 10.0%). The polar lipids consisted of diphosphatidylglycerol and phosphatidylglycerol. The genomic DNA G + C content of NKC1-2T was 42.5 mol%. On the basis of these findings, strain NKC1-2T is proposed as a novel species in the genus Virgibacillus, for which the name Virgibacillus kimchii sp. nov. is proposed (=KACC 19404T =JCM 32284T). The type strain of Virgibacillus kimchii is NKC1-2T.

ALS-linked mutant SOD1 proteins promote Aß aggregates in ALS through direct interaction with Aß.

Amyotrophic lateral sclerosis (ALS) is a neurodegenerative disease characterized by progressive degeneration of motor neurons. Aggregation of ALS-linked mutant Cu/Zn superoxide dismutase (SOD1) is a hallmark of a subset of familial ALS (fALS). Recently, intracellular amyloid-ß (Aß) is detected in motor neurons of both sporadic and familial ALS. We have previously shown that intracellular Aß specifically interacts with G93A, an ALS-linked SOD1 mutant. However, little is known about the pathological and biological effect of this interaction in neurons. In this study, we have demonstrated that the Aß-binding region is exposed on the SOD1 surface through the conformational changes due to misfolding of SOD1. Interestingly, we found that the intracellular aggregation of Aß is enhanced through the direct interaction of Aß with the Aß-binding region exposed to misfolded SOD1. Ultimately, increased Aß aggregation by this interaction promotes neuronal cell death. Consistent with this result, Aß aggregates was three-fold higher in the brains of G93A transgenic mice than those of non Tg. Our study provides the first direct evidence that Aß, an AD-linked factor, is associated to the pathogenesis of ALS and provides molecular clues to understand common aggregation mechanisms in the pathogenesis of neurodegenerative diseases. Furthermore, it will provide new insights into the development of therapeutic approaches for ALS.

Harmless effects of argon plasma on caudal fin regeneration and embryogenesis of zebrafish: novel biological approaches for safe medical applications of bioplasma.

The argon plasma jet (Ar-PJ) is widely used in medical fields such as dermatology and dentistry, and it is considered a promising tool for cancer therapy. However, the in vivo effects of Ar-PJ for medical uses have not yet been investigated, and there are no biological tools to determine the appropriate clinical dosages of Ar-PJ. In this study, we used the caudal fin and embryo of zebrafish as novel in vivo tools to evaluate the biosafety of Ar-PJ. Typically, Ar-PJ is known to induce cell death in two-dimensional (2D) cell culture systems. By contrast, no detrimental effects of Ar-PJ were shown in our 3D zebrafish systems composed of 2D cells. The Ar-PJ-treated caudal fins grew by an average length of 0.7 mm, similar to the length of the normally regenerating fins. Remarkably, Ar-PJ did not affect the expression patterns of Wnt8a and ß-Catenin, which play important roles in fin regeneration. In the embryo system, 85% of the Ar-PJ-treated embryos hatched, and the lateral length of these embryos was ~3.3 mm, which are equivalent to the lengths of normal embryos. In particular, vasculogenesis, which is the main cellular process during tissue regeneration and embryogenesis, occurred normally under the Ar-PJ dose used in this study. Therefore, our biosafety evaluation tools that use living model systems can be used to provide an experimental guideline to determine the clinically safe dosage of Ar-PJ.

Allium hookeri root extract exerts anti-inflammatory effects by nuclear factor-κB down-regulation in lipopolysaccharide-induced RAW264.7 cells.

BACKGROUND: Allium hookeri (AH) is widely consumed as a vegetable and herbal medicine in southeastern Asia. AH has been reported antioxidant, antimicrobial, improvement of bone health and antidiabetic effects. In the present study, we investigated the inhibitory effect of a methanol extract of AH root (AHE) on inflammatory response in lipopolysaccharide (LPS)-induced RAW264.7 cells. METHODS: Initially, characterization of organic sulfur compounds in AHE was determined using high performance liquid chromatography-electrospray ionization-mass spectrometry (HPLC-ESI-MS). Cells were incubated with LPS and AHE for 24 h. The productions of nitric oxide (NO), reactive oxygen species (ROS), and inflammation-related cytokines were examined. Gene and protein expression of inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) were assessed by polymerase chain reaction and Western blotting. Key factor, nuclear factor kappa B (NF-κB) was also determined. RESULTS: AHE contained organosulfur compounds such as alliin and S-allylcysteine by HPLC-ESI-MS. AHE significantly inhibited NO, ROS, and cytokines production in LPS-induced RAW264.7 cells. In addition, AHE treatment inhibited iNOS and COX-2 mRNA and protein levels, leading to a decrease in iNOS-derived NO level. Furthermore, NF-κB activation was, at least in part, suppressed by AHE treatment. CONCLUSION: Our data suggest that AHE treatment inhibits the inflammation condition through suppression of iNOS and COX-2 expression via NF-κB down-regulation.

Optimization of Herbicidin A Production in Submerged Culture of Streptomyces scopuliridis M40.

Herbicidin A is a potent herbicide against dicotyledonous plants as well as an antibiotic against phytopathogens. In this study, fermentation parameters for herbicidin A production in submerged culture of Streptomyces scopuliridis M40 were investigated. The herbicidin A concentration varied with the C/N ratio. High C/N ratios (>4) resulted in a herbicidin A production of more than 900 mg/l, whereas maximally 600 mg/l was obtained at ratios between 1 and 3.5. In 5-L batch fermentation, there was a positive correlation between the oxygen uptake rate (OUR) and herbicidin A production. Once the OUR increased, the substrate consumption rate increased, leading to an increase in volumetric productivity. Mechanical shear force affected the hyphal morphology and OUR. When the medium value of hyphal size ranged from 150 to 180 µm, high volumetric production of herbicidin A was obtained with OUR values >137 mg O2/l·h. The highest herbicidin A concentration of 956.6 mg/l was obtained at 500 rpm, and coincided with the highest relative abundance of hyphae of 100-200 µm length and the highest OUR during cultivation. Based on a constant impeller tip speed, which affects hyphal morphology, herbicidin A production was successfully scaled up from a 5-L jar to a 500-L pilot vessel.

Weissella cibaria WIKIM28 ameliorates atopic dermatitis-like skin lesions by inducing tolerogenic dendritic cells and regulatory T cells in BALB/c mice.

The occurrence of atopic dermatitis (AD), a chronic inflammatory skin disease, has been increasing steadily in children and adults in recent decades. In this study, we evaluated the ability of the lactic acid bacterium Weissella cibaria WIKIM28 isolated from gatkimchi, a Korean fermented vegetable preparation made from mustard leaves, to suppress the development of AD induced by 2,4-dinitrochlorobenzene in a murine model. Oral administration of W. cibaria WIKIM28 reduced AD-like skin lesions, epidermal thickening, and serum immunoglobulin E levels. Furthermore, the production of type 2 helper T (Th2) cytokines such as interleukin (IL)-4, IL-5, and IL-13 decreased in peripheral lymph node cells. Moreover, the intake of W. cibaria WIKIM28 increased the proportion of CD4+CD25+Foxp3+ regulatory T (Treg) cells in mesenteric lymph nodes (MLNs) and IL-10 levels in polyclonally stimulated MLN cells. In conclusion, the oral administration of W. cibaria WIKIM28 isolated from gatkimchi ameliorated AD-like symptoms by suppressing allergic Th2 responses and inducing Treg responses. These results suggest that W. cibaria WIKIM28 may be applicable as a probiotic for the prevention and amelioration of AD.