• Journal of Microbiology and Biotechnology
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• v.16 no.8
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• pp.1285-1291
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• 2006

The proline utilization (put) operon of Vibrio vulnificus consists of the putAP genes encoding a proline dehydrogenase and proline permease. The result of put-lux transcriptional fusion analysis suggests that the V vulnificus putAP operon is not autoregulated by the PutA protein. A putR null mutation decreased proline dehydrogenase activity and the level of the put transcripts, indicating that transcription of putAP is under the positive control of PutR. The deduced amino acid sequence of the putR was similar to those reported from other bacteria with high levels of identity. Chromatin IP and GST pull-down assays revealed that PutR specifically binds to the putAP promoter region in vivo, and interacts with CRP in vitro. Taken together, the results suggested that PutR exerts its effect on putAP expression by directly interacting with CRP bound to the upstream region of P$_{put}$.

• Animal Bioscience
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• v.37 no.6
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• pp.1021-1030
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• 2024

Objective: R-loops are DNA:RNA triplex hybrids, and their metabolism is tightly regulated by transcriptional regulation, DNA damage response, and chromatin structure dynamics. R-loop homeostasis is dynamically regulated and closely associated with gene transcription in mouse zygotes. However, the factors responsible for regulating these dynamic changes in the R-loops of fertilized mouse eggs have not yet been investigated. This study examined the functions of candidate factors that interact with R-loops during zygotic gene activation. Methods: In this study, we used publicly available next-generation sequencing datasets, including low-input ribosome profiling analysis and polymerase II chromatin immunoprecipitation-sequencing (ChIP-seq), to identify potential regulators of R-loop dynamics in zygotes. These datasets were downloaded, reanalyzed, and compared with mass spectrometry data to identify candidate factors involved in regulating R-loop dynamics. To validate the functions of these candidate factors, we treated mouse zygotes with chemical inhibitors using in vitro fertilization. Immunofluorescence with an anti-R-loop antibody was then performed to quantify changes in R-loop metabolism. Results: We identified DEAD-box-5 (DDX5) and histone deacetylase-2 (HDAC2) as candidates that potentially regulate R-loop metabolism in oocytes, zygotes and two-cell embryos based on change of their gene translation. Our analysis revealed that the DDX5 inhibition of activity led to decreased R-loop accumulation in pronuclei, indicating its involvement in regulating R-loop dynamics. However, the inhibition of histone deacetylase-2 activity did not significantly affect R-loop levels in pronuclei. Conclusion: These findings suggest that dynamic changes in R-loops during mouse zygote development are likely regulated by RNA helicases, particularly DDX5, in conjunction with transcriptional processes. Our study provides compelling evidence for the involvement of these factors in regulating R-loop dynamics during early embryonic development.

• BMB Reports
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• v.34 no.2
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• pp.144-149
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• 2001

Antioxidant enzymes, scavengers of the reactive oxygen intermediate (ROI), are involved in numerous defense systems in cells. In the present study, we investigated the effects of the hot-water extracts of two medicinally potent mushrooms (Ganoderma lucidum and Phellinus linteus) on the activity and expression of antioxidant enzymes in vitro and in vivo. The mushroom extracts stimulated the catalase activity in a dose-dependent manner in vitro, whereas the other antioxidant enzymes (such as superoxide dismutase (SOD), glutathione peroxidase (GPx)) were unaffected by the extracts. The catalytic activity of catalase in the liver and brain was significantly increased after the oral treatment of the mushroom extracts (2.5 g/kg) to ICR mice for 2 months. Western blot analysis of the liver and brain tissues revealed that the expression level of catalase in the mice, treated with both mushroom extracts, was significantly increased compared to that of the control mice. However, the level of the SOD expression in the mice treated with the natural product extracts was unchanged under the same experimental conditions. Although the mechanisms for the stimulatory effect of the catalase expression by these extracts remains unclear, these results suggest that the ingredients of the Ganoderma lucidum and Phellinus linteus extracts act as an activator of catalase, and regulate the expression of catalase at the translational or transcriptional level.

• Biomolecules & Therapeutics
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• v.25 no.6
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• pp.641-647
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• 2017

Galangin (3,5,7-trihydroxyflavone) is a polyphenolic compound abundant in honey and medicinal herbs, such as Alpinia officinarum. In this study, we investigated the anti-inflammatory effects of galangin under in vitro and in vivo neuroinflammatory conditions caused by polyinosinic-polycytidylic acid (poly(I:C)), a viral mimic dsRNA analog. Galangin suppressed the production of nitric oxide, reactive oxygen species, and pro-inflammatory cytokines in poly(I:C)-stimulated BV2 microglia. On the other hand, galangin enhanced anti-inflammatory interleukin (IL)-10 production. Galangin also suppressed the expression of pro-inflammatory markers in poly(I:C)-injected mouse brains. Further mechanistic studies showed that galangin inhibited poly(I:C)-induced nuclear factor (NF)-${\kappa}B$ activity and phosphorylation of Akt without affecting MAP kinases. Interestingly, galangin increased the expression and transcriptional activity of peroxisome proliferator-activated receptor (PPAR)-${\gamma}$, known to play an anti-inflammatory role. To investigate whether PPAR-${\gamma}$ is involved in the anti-inflammatory function of galangin, BV2 cells were pre-treated with PPAR-${\gamma}$ antagonist before treatment of galangin. We found that PPAR-${\gamma}$ antagonist significantly blocked galangin-mediated upregulation of IL-10 and attenuated the inhibition of tumor necrosis factor (TNF)-${\alpha}$ and IL-6 in poly(I:C)-stimulated microglia. In conclusion, our data suggest that PI3K/Akt, NF-${\kappa}B$, and PPAR-${\gamma}$ play a pivotal role in mediating the anti-inflammatory effects of galangin in poly(I:C)-stimulated microglia.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.20
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• pp.8581-8586
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• 2014

Activin is a multifunctional growth and differentiation factor of the growth factor-beta (TGF-${\beta}$) superfamily, which inhibits the proliferation of colon cancer cells. It induces phosphorylation of intracellular signaling molecules (Smads) by interacting with its type I and type II receptors. Previous studies showed that human activin receptor-interacting protein 2 (hARIP2) can reduce activin signaling by interacting with activin type II receptors; however, the activity of hARIP2 in colon cancer has yet to be detailed. In vitro, overexpression of hARIP2 reduced activin-induced transcriptional activity and enhanced cell proliferation and colony formation in human colon cancer HCT8 cells and SW620 cells. Also, hARIP2 promoted colon cancer cell apoptosis, suggesting that a vital role in the initial stage of colon carcinogenesis. In vivo, immunohistochemistry revealed that hARIP2 was expressed more frequently and much more intensely in malignant colon tissues than in controls. These results indicate that hARIP2 is involved in human colon tumorigenesis and could be a predictive maker for colon carcinoma aggressiveness.

• Journal of Ginseng Research
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• v.41 no.1
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• pp.43-51
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• 2017

Background: BIOGF1K, a compound K-rich fraction prepared from the root of Panax ginseng, is widely used for cosmetic purposes in Korea. We investigated the functional mechanisms of the anti-inflammatory and antioxidative activities of BIOGF1K by discovering target enzymes through various molecular studies. Methods: We explored the inhibitory mechanisms of BIOGF1K using lipopolysaccharide-mediated inflammatory responses, reporter gene assays involving overexpression of toll-like receptor adaptor molecules, and immunoblotting analysis. We used the 2,2-diphenyl-1-picrylhydrazyl (DPPH) assay to measure the antioxidative activity. We cotransfected adaptor molecules, including the myeloid differentiation primary response gene 88 (MyD88) and Toll/interleukin-receptor domain containing adaptor molecule-inducing interferon-${\beta}$ (TRIF), to measure the activation of nuclear factor (NF)-${\kappa}B$ and interferon regulatory factor 3 (IRF3). Results: BIOGF1K suppressed lipopolysaccharide-triggered NO release in macrophages as well as DPPH-induced electron-donating activity. It also blocked lipopolysaccharide-induced mRNA levels of interferon-${\beta}$ and inducible nitric oxide synthase. Moreover, BIOGF1K diminished the translocation and activation of IRF3 and NF-${\kappa}B$ (p50 and p65). This extract inhibited the upregulation of NF-${\kappa}B$-linked luciferase activity provoked by phorbal-12-myristate-13 acetate as well as MyD88, TRIF, and inhibitor of ${\kappa}B$ ($I{\kappa}B{\alpha}$) kinase ($IKK{\beta}$), and IRF3-mediated luciferase activity induced by TRIF and TANK-binding kinase 1 (TBK1). Finally, BIOGF1K downregulated the NF-${\kappa}B$ pathway by blocking $IKK{\beta}$ and the IRF3 pathway by inhibiting TBK1, according to reporter gene assays, immunoblotting analysis, and an AKT/$IKK{\beta}$/TBK1 overexpression strategy. Conclusion: Overall, our data suggest that the suppression of $IKK{\beta}$ and TBK1, which mediate transcriptional regulation of NF-${\kappa}B$ and IRF3, respectively, may contribute to the broad-spectrum inhibitory activity of BIOGF1K.

• Journal of Life Science
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• v.23 no.8
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• pp.1041-1049
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• 2013

The root of Polygala radix has been widely known as an oriental traditional medicinal stuff that improves memory. However, its mechanism of action remains unclear. In this study, the effect of Polygala radix hot water extracts (PRHWE) on cognitive function related to the activity of acetylcholinesterase (AchE) derived from neural cells (PC12) in addition to antioxidant activity was examined both in a cell-free system and live cells. First, in the study on cell viability using an MTT assay, PRHWE did not exhibit any cell toxicity at 0.1% (w/v) or below. It also was observed that PRHWE increased the scavenging activity of DPPH radical, hydrogen peroxide and superoxide, reducing power in a dose-dependent manner. In particular, PRHWE had a protective effect on DNA oxidation induced by hydroxyl radicals. Additionally, it inhibited the production of inducible nitric oxide in neuronal cells. Furthermore, the AchE activity decreased with increasing concentrations. In addition, PRHWE increased the expression level of SOD-1 and NOS-2 in PC12 cells. Moreover, the transcriptional activities of p53 and NF-${\kappa}B$ were reduced in the presence of PRHWE in an experiment using a reporter gene assay. Therefore, these results prove that PRHE has antioxidative and protective effects on neuronal cells, suggesting that it may have great potential as a therapeutic agent for human health.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.21
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• pp.9211-9216
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• 2014

CXCR7 is involved in tumor development and metastasis in multiple malignancies. However, the function and molecular mechanisms of action of CXCR7 in human cervical cancer are still unclear. In the present study a loss of-function approach was used to observe the effects of recombinant CXCR7 specific small interfering RNA pBSilence1.1 plasmids on biological behavior including proliferative activity and invasive potential, as indicated by MTT assays with the cervical cancer SiHa cell line in vitro. Reverse transcription polymerase chain reaction and Western blotting revealed that CXCR7 was downregulated in transfected compared with control cells, associated with inhibited cell growth, invasiveness and migration. The expression of CXCR7 and CXCL12 was also determined immunohistochemically in 152 paraffin-embedded, cervical squamous cell carcinoma (CSCC) and cervical intraepithelial neoplasia (CIN), or normal cervical epithelial to assess clinico-pathological pattern and CXCR7 status with respect to cell differentiation and lymph node metastasis in Uighur patients with CSCC. CXCR7 and CXCL12 expression was higher in cervical cancer than CIN and normal cervical mucosa, especially in those with higher stage and lymph node metastasis. CXCL12 appeared to be positively regulated by CXCR7 at the post-transcriptional level in CSCC. We propose that aberrant expression of CXCR7 plays a role in carcinogenesis, differentiation and metastasis of CSCC, implying its use as a potential target for clinical biomarkers in differentiation and lymph node metastasis.

• The Korean Journal of Physiology and Pharmacology
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• v.13 no.3
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• pp.161-168
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• 2009

In the peripheral nerves, injury-induced cytokines and growth factors perform critical functions in the activation of both the MEK/ERK and JAK/STAT3 pathways. In this study, we determined that nerve injury-induced ERK activation was temporally correlated with STAT3 phosphorylation at the serine 727 residue. In cultured Schwann cells, we noted that ERK activation is required for the serine phosphorylation of STAT3 by neuropoietic cytokine interleukin-6 (IL-6). Serine phosphorylated STAT3 by IL-6 was transported into Schwann cell nuclei, thereby indicating that ERK may regulate the transcriptional activity of STAT3 via the induction of serine phosphorylation of STAT3. Neuregulin-1 (NRG) also induced the serine phosphorylation of STAT3 in an ERK-dependent fashion. In contrast with the IL-6 response, serine phosphorylated STAT3 induced by NRG was not detected in the nucleus, thus indicating the non-nuclear function of serine phosphorylated STAT3 in response to NRG. Finally, we determined that the inhibition of ERK prevented injury-induced serine phosphorylation of STAT3 in an ex-vivo explants culture of the sciatic nerves. Collectively, the results of this study show that ERK may be an upstream kinase for the serine phosphorylation of STAT3 induced by multiple stimuli in Schwann cells after peripheral nerve injury.

• Nutrition Research and Practice
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• v.12 no.2
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• pp.110-117
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• 2018

BACKGROUND/OBJECTIVES: Non-alcoholic fatty liver disease (NAFLD) is a leading cause of chronic liver disease and is closely associated with metabolic syndrome. In the present study, we observed the effect of ethanol extract of Allium fistulosum (EAF) on NAFLD and have suggested the possibility of using EAF as a natural product for application in the development of a treatment for NAFLD. MATERIALS/METHODS: The preventive effect on hepatic lipid accumulation was estimated by using an oleic acid (OA)-induced NAFLD model in vitro and a Western diet (high-fat high-sucrose; WD)-induced obese mouse model. Animals were divided into three groups (n = 7): normal diet group (ND), WD group, and WD plus 1% EAF group. RESULTS: EAF reduced OA-stimulated lipid accumulation in HepG2 cells in the absence of cellular cytotoxicity and significantly blocked transcriptional activation of sterol regulatory element-binding protein 1 and fatty acid synthase genes. Subsequently, we investigated these effects in vivo in mice fed either ND or WD in the presence or absence of EAF supplementation. In comparison to the ND controls, the WD-fed mice exhibited increases in body weight, liver weight, epididymal fat weight, and accumulation of fat in hepatocytes, and these effects were significantly attenuated by EAF supplementation. CONCLUSIONS: Allium fistulosum attenuates the development of NAFLD, and EAF elicits anti-lipogenic activity in liver. Therefore, EAF represents a promising candidate for use in the development of novel therapeutic drugs or drug combinations for the prevention and treatment of NAFLD.