• Journal of Microbiology and Biotechnology
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• 제22권6호
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• pp.742-753
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• 2012

Copper-containing compounds are introduced into the environment through agricultural chemicals, mining, and metal industries and cause severe detrimental effects on ecosystems. Certain microorganisms exposed to these stressors exhibit molecular mechanisms to maintain intracellular copper homeostasis and avoid toxicity. We have previously reported that the soil bacterial isolate Achromobacter sp. AO22 is multi-heavy metal tolerant and exhibits a mer operon associated with a Tn21 type transposon. The present study reports that AO22 also hosts a unique cop locus encoding copper homeostasis determinants. The putative cop genes were amplified from the strain AO22 using degenerate primers based on reported cop and pco sequences, and a constructed 10,552 base pair contig (GenBank Accession No. GU929214). BLAST analyses of the sequence revealed a unique cop locus of 10 complete open reading frames, designated copSRABGOFCDK, with unusual separation of copCD from copAB. The promoter areas exhibit two putative cop boxes, and copRS appear to be transcribed divergently from other genes. The putative protein CopA may be a copper oxidase involved in export to the periplasm, CopB is likely extracytoplasmic, CopC may be periplasmic, CopD is cytoplasmic/inner membrane, CopF is a P-type ATPase, and CopG, CopO, and CopK are likely copper chaperones. CopA, B, C, and D exhibit several potential copper ligands and CopS and CopR exhibit features of two-component regulatory systems. Sequences flanking indicate the AO22 cop locus may be present within a genomic island. Achromobacter sp. strain AO22 is thus an ideal candidate for understanding copper homeostasis mechanisms and exploiting them for copper biosensor or biosorption systems.

• Journal of Microbiology and Biotechnology
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• 제29권1호
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• pp.151-159
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• 2019

Lipoteichoic acid isolated from Lactobacillus plantarum K8 (pLTA) alleviates lipopolysaccharide (LPS)-induced excessive inflammation through inhibition of $TNF-{\alpha}$ and interleukin (IL)-6. In addition, pLTA increases the survival rate of mice in a septic shock model. In the current study, we have found that pLTA contributes to homeostasis through regulation of pro- and anti-inflammatory cytokine production. In detail, pLTA decreased the production of IL-10 by phorbol-12-myristate-13-acetate (PMA)-differentiated THP-1 cells stimulated with prostaglandin E2 (PGE-2) and LPS. However, $TNF-{\alpha}$ production which was inhibited by PGE-2+LPS increased by pLTA treatment. The regulatory effects of IL-10 and $TNF-{\alpha}$ induced by PGE-2 and LPS in PMA-differentiated THP-1 cells were mediated by pLTA, but not by other LTAs isolated from either Staphylococcus aureus (aLTA) or L. sakei (sLTA). Further studies revealed that pLTA-mediated IL-10 inhibition and $TNF-{\alpha}$ induction in PGE-2+LPS-stimulated PMA-differentiated THP-1 cells were mediated by dephosphorylation of p38 and phosphorylation of c-Jun N-terminal kinase (JNK), respectively. Reduction of pLTA-mediated IL-10 inhibited the metastasis of breast cancer cells (MDA-MB-231), which was induced by IL-10 or conditioned media prepared from PGE-2+LPS-stimulated PMA-differentiated THP-1 cells. Taken together, our data suggest that pLTA contributes to inflammatory homeostasis through induction of repressed pro-inflammatory cytokines as well as inhibition of excessive anti-inflammatory cytokines.

• Molecules and Cells
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• 제25권1호
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• pp.124-130
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• 2008

Astrocyte ion channels participate in ionic homeostasis in the brain. Inward rectifying potassium channels (Kir channels) in astrocytes have been particularly implicated in $K^+$ homeostasis because of their high open probability at resting potential and their increased conductance at high concentrations of extracellular $K^+$. We examined the expression of the Kir2.1 subunit, one of the Kir channel subunits, in the mouse brain by immunohistochemistry. Kir2.1 channels were widely distributed throughout the brain, with high expression in the olfactory bulb and the cerebellum. Interestingly, they were abundantly expressed in astrocytes of the olfactory bulb, while astrocytes in other brain regions including the hippocampus did not show any detectable expression. However, Kir2.1 channel-expressing cells were dramatically increased in the hippocampus by kainic acid-induced seizure and the cells were glial fibrillary acidic protein (GFAP)-positive, which confirms that astrocytes in the hippocampus express Kir2.1 channels under pathological conditions. Our results imply that Kir2.1 channels in astrocyte may be involved in buffering $K^+$ against accumulated extracellular $K^+$ caused by neuronal hyperexcitability under phathophysiological conditions.

• BMB Reports
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• 제50권4호
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• pp.162-163
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• 2017

RNA polymerase II-interacting the Set2 methyltransferase co-transcriptionally methylates histone H3 at lysine 36 within the body of genes. This modification facilitates histone deacetylation by Rpd3S HDAC in 3' transcribed regions to suppress cryptic initiation and slow elongation. Although this pathway is important for global deacetylation, no strong effects have been seen on genome-wide transcription under optimized laboratory conditions. In contrast, this pathway slows the kinetics of mRNA induction when target genes are induced upon environmental changes. Interestingly, a majority of Set2-repressed genes are overlapped by a lncRNA transcription that targets H3K36 methylation and deacetylation by Rpd3S HDAC to mRNA promoters. Furthermore, this pathway delays the induction of many cryptic transcripts upon environmental changes. Therefore, the Set2-Rpd3S HDAC pathway functions to fine-tune expression dynamics of mRNAs and ncRNAs.

• BMB Reports
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• 제52권2호
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• pp.127-132
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• 2019

Cells must fine-tune their gene expression programs for optimal cellular activities in their natural growth conditions. Transcriptional memory, a unique transcriptional response, plays a pivotal role in faster reactivation of genes upon environmental changes, and is facilitated if genes were previously in an active state. Hyper-activation of gene expression by transcriptional memory is critical for cellular differentiation, development, and adaptation. TREM (Transcriptional REpression Memory), a distinct type of transcriptional memory, promoting hyper-repression of unnecessary genes, upon environmental changes has been recently reported. These two transcriptional responses may optimize specific gene expression patterns, in rapidly changing environments. Emerging evidence suggests that they are also critical for immune responses. In addition to memory B and T cells, innate immune cells are transcriptionally hyperactivated by restimulation, with the same or different pathogens known as trained immunity. In this review, we briefly summarize recent progress in chromatin-based regulation of transcriptional memory, and its potential role in immune responses.

• Natural Product Sciences
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• 제25권2호
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• pp.165-171
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• 2019

Although the functions of a standardized extract of Gingko biloba leaves (EGb $761^{(R)}$) has been reported with regard to neurobiological properties, no attention has been paid to the impact of EGb $761^{(R)}$ on the neuronal regulation of energy homeostasis. To evaluate the hypothesis that EGb $761^{(R)}$ affect the secretion of peptide tyrosine tyrosine (PYY) and the activation of free fatty acid receptor 4 (FFA4), which are involved in the neuronal circuitries that control energy homeostasis by inducing the transfer of information about the influx of energy to the brain, we examined whether EGb $761^{(R)}$ can stimulate PYY secretion in the enteroendocrine NCI-H716 cells and if EGb $761^{(R)}$ can activate FFA4 in FFA4-expressing cells. In NCI-H716 cells, EGb $761^{(R)}$ stimulated PYY secretion and the EGb $761^{(R)}$-induced PYY secretion was involved in the increase in intracellular $Ca^{2+}$ concentration and the activation of FFA4. Furthermore, in FFA4-expressing cells, EGb $761^{(R)}$ activated FFA4. These results suggest that EGb $761^{(R)}$ may affect the control of energy homeostasis via the regulation of PYY secretion and FFA4 activation.

• 한국해양바이오학회지
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• 제15권1호
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• pp.24-32
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• 2023

The Laminaria japonica Aresch (Sea tangle) belongs to the brown algae and has a long history as a food material in Asia, including Korea. Recent studies have found that the fermented Sea tangle extract (FST) inhibited the differentiation of osteoclasts and protected osteoblasts from oxidative damage. This study aims to explore the possibility that FST can induce the differentiation of osteoblasts and identify the responsible mechanism. According to our results, FST induced differentiation into osteogenic cells in the presence of osteoblastic MC3T3-E1 cells under non-toxic conditions.. This finding was confirmed by phalloidin staining, increased alkaline phosphatase activity, and calcium deposition. Additionally, it was found that this process was achieved by increasing the expression of key factors involved in osteoblast differentiation, such as runt-related transcription factor-2, osterix, β-catenin, and bone morphogenetic protein-2. Moreover, FST increased autophagy, which may contribute to the maintenance of the bone formation homeostasis, and is associated with the activation of the phosphatidylinositol 3-kinase/Akt and mitogen-activated protein kinase signaling pathways. Although further research about the bioactive substances contained in FST and the tests of their efficacy are required, the results of this study indicate that FST has incredible applicability as a functional material for maintaining the bone homeostasis.

• Molecules and Cells
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• 제38권6호
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• pp.528-534
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• 2015

Hypoxia-inducible factor (HIF) is a key regulator of tumor growth and angiogenesis. Recent studies have shown that, BIX01294, a G9a histone methyltransferase (HMT)-specific inhibitor, induces apoptosis and inhibits the proliferation, migration, and invasion of cancer cells. However, not many studies have investigated whether inhibition of G9a HMT can modulate HIF-$1{\alpha}$ stability and angiogenesis. Here, we show that BIX01294 dose-dependently decreases levels of HIF-$1{\alpha}$ in HepG2 human hepatocellular carcinoma cells. The half-life of HIF-$1{\alpha}$, expression of proline hydroxylase 2 (PHD2), hydroxylated HIF-$1{\alpha}$ and von Hippel-Lindau protein (pVHL) under hypoxic conditions were decreased by BIX01294. The mRNA expression and secretion of vascular endothelial growth factor (VEGF) were also significantly reduced by BIX01294 under hypoxic conditions in HepG2 cells. BIX01294 remarkably decreased angiogenic activity induced by VEGF in vitro, ex vivo, and in vivo, as demonstrated by assays using human umbilical vein endothelial cells (HUVECs), mouse aortic rings, and chick chorioallantoic membranes (CAMs), respectively. Furthermore, BIX01294 suppressed VEGF-induced matrix metalloproteinase 2 (MMP2) activity and inhibited VEGF-induced phosphorylation of VEGF receptor 2 (VEGFR-2), focal adhesion kinase (FAK), and paxillin in HUVECs. In addition, BIX01294 inhibited VEGF-induced formation of actin cytoskeletal stress fibers. In conclusion, we demonstrated that BIX01294 inhibits HIF-$1{\alpha}$ stability and VEGF-induced angiogenesis through the VEGFR-2 signaling pathway and actin cytoskeletal remodeling, indicating a promising approach for developing novel therapeutics to stop tumor progression.

• 지역사회간호학회지
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• 제5권2호
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• pp.203-215
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• 1994

The purpose of this study was to investigate the needs for exercise of adult inpatients and ultimately to provide basic data for planning nursing intervention of patients who need exercise. The tool used for this study was a structured questionnaire which consisted of 42 items. The test items were classified into seven factors. The seven factors of the needs for exercise were need for achievement, need for activity, need for affiliation, need for autonomy, need for catharsis, need for homeostasis, and need for exhibition. Subjects of this study were 127 patients in two general hospitals in Seoul, and one general hospital in Chun Ann City. The needs of exercise were identified and the data were analyzed by gender, age, occupation, education level, monthly income, size of patient room, patient group who requires exercise and the other patient group who requires bed rest, using one-way ANOVA and Scheffe test as post-hoc. The findings of this study were as follows ; 1) Among the needs for exercise of adult patients, the highest level of the needs was the need for homeostasis. The next highest was the need for achievement, then need for activity, need for catharsis, need for autonomy, need for affiliation, and the lowest was the need for exhibition. 2) Maintaining physical fitness stood first in the need for homeostasis, relieving psychological and physical powerlessness in the need for activity, mood diversion in the need for catharsis, happiness of the family in the need for affiliation, maintaining the balanced body figure in the need for exhibition, practicing planned life in the need for achievement, and improving the ability to overcome the crisis in the need for autonomy. 3) Male patients exhibited the higher level of the needs than female patients in all factors except the need for exhibition and homeostasis. 4) There was no statistical difference in the needs between age, occupation, monthly income, and the size of patient room. 5) The need for achievement was high as the level of education goes higher. 6) The patients who performed regular exercise before admission had higher needs for activity, achievement, and autonomy, compared with the patients who did not perform the regular exercise before admission. 7) There was no statistical difference in the needs between patient group who requires exercise and the other patient group who requires bed rest. The need for homeostasis was the highest in both groups. The results from this study suggest that the need for exercise of adult inpatients should be assessed before planning exercise intervention.

• Journal of Ginseng Research
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• 제44권4호
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• pp.580-592
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• 2020

Background: Radix et Rhizoma Ginseng (thereafter called ginseng) has been used as a medicinal herb for thousands of years to maintain people's physical vitality and is also a non-organ-specific cancer preventive and therapeutic traditional medicine in several epidemiologic and preclinical studies. Owing to few toxic side effects and strong enhancement on body immunity, ginseng has admirable application potential and value in cancer chemoprevention. The study aims at investigating the chemopreventive effects of ginseng on cutaneous carcinoma and the underlying mechanisms. Methods: The mouse skin cancer model was induced by 7,12-dimethylbenz[a]anthracene/12-O-tetradecanoylphorbol-13-acetate. Ultraperformance liquid chromatography/mass spectrometry was used for identifying various ginsenosides, the main active ingredients of ginseng. Comprehensive approaches (including network pharmacology, bioinformatics, and experimental verification) were used to explore the potential targets of ginseng. Results: Ginseng treatment inhibited cutaneous carcinoma in terms of initiation and promotion. The content of Rb1, Rb2, Rc, and Rd ginsenosides was the highest in both mouse blood and skin tissues. Ginseng and its active components well maintained the redox homeostasis and modulated the immune response in the model. Specifically, ginseng treatment inhibited the initiation of skin cancer by enhancing T-cell-mediated immune response through upregulating HSP27 expression and inhibited the promotion of skin cancer by maintaining cellular redox homeostasis through promoting nuclear translocation of Nrf2. Conclusion: According to the study results, ginseng can be potentially used for cutaneous carcinoma as a chemopreventive agent by enhancing cell-mediated immunity and maintaining redox homeostasis with multiple components, targets, and links.