• Journal of Physiology & Pathology in Korean Medicine
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• v.24 no.2
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• pp.228-235
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• 2010

This study was performed to investigate the memory enhancing effect of Poria cocos Wolf (Hoelen cum radix) against scopolamine-induced amnesia in Sprague-Dawley (SD) rats. To induce amnesia, scopolamine (0.75 mg/kg) was intraperitonically injected into SD rats 30 min before starting behavior tests. We have conducted Morris water-maze and Y-maze tests to monitor learning and memory functions. Poria cocos effectively reversed scopolamine-induced memory impairment in SD rats which was represented by an improvement of mean escape latency in water-maze test and spontaneous alterations in Y-maze test. To elucidate possible molecule mechanism, we have measured mRNA as well as protein expression of acetylcholine esterase (AchE), choline acetyltransferase (ChAT), muscarinic acetylcholine receptor (mAchR), and brain-derived neurotrophic factor (BDNF) using RT-PCR and Western blot analysis, respectively. Poria cocos increased mRNA levels of ChAT and mAchR in rat hippocampus compared with those in the scopolamine-injected amnesic group. In addition, protein expression of ChAT and BDNF was also elevated by Poria cocos intake. Furthermore, as an upstrem regulator, the activation of cAMP response element-binding protein (CREB) was assessed by immunohistochemistry. In this immunohistochemical analysis, the phosphorylation of CREB (p-CREB) was reduced by scopolamine injection, which was restored back to control levels by administration of Poria cocos. These results suggest that Poria cocos may improve memory and cognitive deficit in amnesia and have therapeutic potentials through up-regulation of ChAT, mAchR, and BDNF, which seemed to be mediated by activation of CREB.

• Microbiology and Biotechnology Letters
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• v.40 no.1
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• pp.50-56
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• 2012

The Wnt/${\beta}$-catenin signaling pathway regulates diverse developmental processes and adult tissue homeostasis. Inappropriate regulation of this pathway has been associated with human diseases, such as cancers, osteoporosis, and Alzheimer's disease. Using a cell-based chemical screening with natural compounds, we discovered silybin, a plant flavonoid isolated from the Silybum marianum, which activated the Wnt/${\beta}$-catenin signaling pathway in a synergy with Wnt3a-conditioned medium (Wnt3a-CM). In the presence of Wnt3a-CM, silybin up-regulated ${\beta}$-catenin response transcription (CRT) in HEK293-FL reporter cells and 3T3-L1 preadipocytes through stabilization of intracellular ${\beta}$-catenin protein. Silybin and Wnt3a-CM synergistically reduced expression of important adipocyte marker genes including peroxisome-proliferator-activated $receptor{\gamma}$ ($PPAR{\gamma}$) and CAATT enhancer-binding protein ${\alpha}$ (C/$EBP{\alpha}$) in 3T3-L1 preadipocytes, accompanied by the activation of Wnt/${\beta}$-catenin signaling pathway. Taken together, our findings indicate that silybin is a small-molecule synergist of the Wnt/${\beta}$-catenin signaling pathway and can be used as a controllable reagent for investigating biological processes that involve the Wnt/${\beta}$-catenin signaling pathway.

• Journal of Life Science
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• v.26 no.2
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• pp.265-274
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• 2016

Toxin-antitoxin (TA) systems are ubiquitous genetic modules that are evolutionally conserved in bacteria and archaea. TA systems composed of an intracellular toxin and its antidote (antitoxin) are currently classified into five types. Commonly, activation of toxins under stress conditions inhibits diverse cellular processes and consequently induces cell death or reversible growth inhibition. These effects of toxins play various physiological roles in such as regulation of gene expression, growth control (stress response), programmed cell arrest, persister cells, programmed cell death, phage protection, stabilization of mobile genetic elements or postsegregational killing of plasmid-free cells. Accordingly, bacterial TA systems are commonly considered as stress-responsive genetic modules. However, molecule screening for activation of toxin in TA system is available as development of antimicrobial agents. In addition, cytotoxic effect induced by toxin is used as effective cloning method with antitoxic effect of antitoxin; consequently cells containing cloning vector inserted a target gene can survive and false-positive transformants are removed. Also, TA system is applicable to efficient single protein production in biotechnology industry because toxins that are site-specific ribonuclease inhibit protein synthesis except for target protein. Furthermore, some TA systems that induce apoptosis in eukaryotic cells such as cancer cells or virus-infected cells would have a wide range of applications in eukaryotes, and it will lead to new ways of treating human disease. In this review, we summarize the current knowledge on bacterial TA systems and their applications.

• Korean Journal of Food Science and Technology
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• v.51 no.1
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• pp.70-80
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• 2019

The aim of this study was to investigate the effects of red ginseng-derived non-saponin fraction (NSF) on inflammatory responses and monocyte-to-macrophage differentiation in RAW264.7 and THP-1. NSF effectively inhibited inflammatory responses by downregulating nitric oxide (NO) production and protein levels of inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2). NSF ($2000{\mu}g/mL$) decreased the levels of NO, iNOS, and COX-2 by 33, 83, and 64%, respectively. NSF inhibited the differentiation of monocyte-to-macrophage by decreasing cell adherence along with downregulation of the cluster of differentiation molecule $11{\beta}$ ($CD11{\beta}$) and CD36. In addition, pro-inflammatory cytokines, such as tumor necrosis factor-alpha, interleukin 6, and monocyte chemoattractant protein 1 (MCP-1), were significantly reduced with NSF treatment. The NSF-mediated inhibition of inflammatory responses was due to the regulation of nuclear factor kappa-light-chain-enhancer of activated B cells ($NF-{\kappa}B$) and nuclear factor (erythroid-derived 2)-like 2 (Nrf2). NSF effectively suppressed the translocation of $NF-{\kappa}B$ into the nucleus, while nuclear Nrf2 and its target protein, heme oxygenase-1, levels were significantly increased.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.47 no.2
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• pp.107-121
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• 2021

Skin hypopigmentation, which is observed in albinism or vitiligo, occurs when melanin synthesis is decreased by genetic, epigenetic, and other factors. To identify drug candidates that can promote melanin synthesis in cells, we screened an epigenetic modulator library consisting of 141 cell-permeable, small molecule drugs. B16/F10 murine melanoma cells were treated with each drug at 0.1 𝜇M and melanin synthesis and cell viability were subsequently monitored. As a result, (-)-neplanocin A, 3-deazaneplanocin A (DZNep), and DZNep hydrochloride were found to increase cellular melanin synthesis without causing cytotoxicity. Because these three structurally related drugs exhibited similar dose-dependent effects on melanin synthesis and cell viability, DZNep was selected as a representative drug for additional experiments. DZNep increased intracellular melanin content and tyrosinase (TYR) activity. DZNep also induced the expression of TYR, tyrosinase-related protein 1 (TYRP1), and dopachrome tautomerase (DCT) at the mRNA and protein levels. DZNep also induced the mRNA and protein expression of microphthalmia-associated transcription factor (MITF), a key regulator of melanin synthesis. DZNep is a specific inhibitor of S-adenosylhomocysteine hydrolase and it caused the accumulation of S-adenosylhomocysteine that inhibits histone methyltransferases in cells. This study suggests that melanogenesis can be modulated by targeting S-adenosylhomocysteine hydrolase in certain cellular contexts.

• Journal of Life Science
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• v.33 no.6
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• pp.463-470
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• 2023

Desmarestia tabacoides Okamura is a brown macroalgae that is found worldwide. Although several genera of Desmarestia have been reported as having anti-tumorigenic, anti-melanogenic, and photoprotective properties, the anti-inflammatory activity of D. tabacoides Okamura has not yet been evaluated. In this study, we analyzed the anti-inflammatory mechanisms of D. tabacoides Okamura ethanol extract (DTEE) via the inhibition of nitric oxide (NO) and prostaglandin (PG) E₂ production and the expression of their corresponding enzymes, inducible NO synthase (iNOS), and cyclooxygenase (COX)-2. In addition, their upstream signaling molecules were evaluated by Western blot analysis, such as nuclear factor (NF)-κB, mitogen-activated protein kinase (MAPK), and phosphoinositide-3-kinase (PI3K)/Akt, in lipopolysaccharide (LPS)-stimulated RAW 264.7 cells. The DTEE treatment significantly inhibited LPS-induced NO and PGE₂ production as well as the expression of their corresponding enzymes, iNOS, and COX-2 without cytotoxicity. The stimulated transcription factor NF-κB and upstream signaling molecules extracellular signal-regulated kinase (ERK), c-Jun NH₂-terminal kinase (JNK), and p38 were attenuated by the DTEE treatment, which was statistically significant, while Akt did not provide any inhibitory effect. Moreover, the DTEE treatment significantly mitigated the LPS-activated adaptor molecules, toll-like receptor 4 (TLR4), and myeloid differentiation primary response 88 (MyD88) in the RAW 264.7 cells. These results suggest that DTEE attenuates TLR4-mediated inflammatory responses by inhibiting NF-κB activation and suppressing MAPK phosphorylation in LPS-stimulated RAW 264.7 cells.

• Journal of Life Science
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• v.33 no.10
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• pp.776-782
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• 2023

Silymarin, which is derived from dried Silybum marianum (milk thistle) seeds and fruits, possesses various beneficial properties, such as hepatoprotective, antioxidative, anti-inflammatory, and anticancer activity. This research aimed to explore the antioxidative activity of silymarin against oxidative stress and understand its molecular mechanism in RAW 264.7 cells. The study employed cell viability and reactive oxygen species (ROS) formation assays and western blot analysis. The results demonstrated that silymarin effectively reduced intracellular ROS levels induced by lipopolysaccharide (LPS) in a dose-dependent manner without causing any cytotoxic effects. Moreover, silymarin treatment significantly upregulated the expression of heme oxygenase (HO)-1, a phase II enzyme known for its potent antioxidative activity. Additionally, silymarin treatment significantly induced the expression of nuclear factor-erythroid 2 p45-related factor (Nrf) 2, a transcription factor responsible for regulating antioxidative enzymes, which was consistent with the upregulated HO-1 expression. To investigate the involvement of key signaling pathways in maintaining cellular redox homeostasis against oxidative stress, the phosphorylation status of mitogen-activated protein kinase (MAPK) and phosphoinositide 3-kinase (PI3K) was estimated by western blot analysis. The results showed that silymarin potently induced HO-1 expression, which was mediated by the phosphorylation of p38 MAPK. To further validate the antioxidative potential of silymarin-induced HO-1 expression, tert-butyl hydroperoxide (t-BHP)-induced oxidative damage was employed and attenuated by silymarin treatment, as identified by a selective inhibitor for each signaling molecule. In conclusion, silymarin robustly enhanced antioxidative activity by inducing HO-1 via the Nrf2/p38 MAPK signaling pathway in RAW 264.7 cells.

• Archives of Pharmacal Research
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• v.25 no.6
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• pp.895-902
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• 2002

Monocytes and macrophages playa major role in defense mechanism of the host response to tumor, in part through the secretion of several potent products and macrophage cytokines. Monocytes and tissue macro phages produce at least two groups of protein mediators of inflammation, interleukin 1 (IL-1) and tumor necrosis factor (TNF). Recent studies emphasizes that TNF and IL-1 modulate the inflammatory function of endothelial cells, leukocytes, and fibroblasts. In this study, our work is directed toward studying the in vitro effects of Korean propolis on the ability to induce cellular and secretory responses in murine macrophage cell line, RAW 264.7. It was found that Water Extract of Korean Propolis (WEP) could activate macro phages by producing cytokines. The production of the macrophage cytokines, IL-1 and TNF-$\alpha$, by RAW 264.7 treated with WEP was examined from 2.5 $\mu\textrm{g}$/ml up to 25 $\mu\textrm{g}$/ml with dose dependent manner. Nitric oxide (NO) production was also increased when cells were exposed to combination of LPS and WEP from 2.5 $\mu\textrm{g}$/ml up to 25 $\mu\textrm{g}$/ml. At high dose of WEP (50 to 100 $\mu\textrm{g}$/ml) used to prescribe for anti-inflammatory and analgesic medicine showed inhibition of NO production in LPS-stimulated macrophage. Besides cytokine production, NO release, surface molecule expression and cell morphologic antigen expression were increased in response to the stimulation by WEP. These results suggested WEP may function through macrophage activation.

• Food Science of Animal Resources
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• v.34 no.5
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• pp.570-575
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• 2014

This study was conducted to compare the effects of two forms of radiation (electron and X-ray; generated by an electron beam accelerator) on the conformation and antigenic properties of hen's egg albumin, ovalbumin (OVA), which was used as a model protein. OVA solutions (2.0 mg/mL) were individually irradiated by electron beam or X-ray at the absorbed doses of 0 (control), 2, 4, 6, 8, and 10 kGy. No differences between the two forms of radiation on the structural properties of OVA were shown by spectrometric and electrophoretic analyses. The turbidity of OVA solution increased and the main OVA bands on polyacrylamide gels disappeared after irradiation, regardless of the radiation source. In competitive indirect enzyme-linked immunosorbent assay, OVA samples irradiated by electron beam or X-ray showed different immunological responses in reactions with monoclonal and polyclonal antibodies (immunoglobulin G) produced against non-irradiated OVA. The results indicate that electron beam irradiation and X-ray irradiation produced different patterns of structural changes to the OVA molecule.

• The Korea Journal of Herbology
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• v.23 no.2
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• pp.169-178
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• 2008

Objectives : Inflammation is important event in the development of vascular diseases including hypertension, atherosclerosis, and restenosis. Injinho-tang(IJHT) has been used as a traditional Korean herbal medicine since ancient times, and today it is widely used as a medication for jaundice associated with inflammation of the liver. The aim of this study was to determine whether IJHT and its components inhibit production of nitrite, an index of NO, and proinflammatory cytokines in lipopolysaccharide (LPS)-treated RAW 264.7 macrophages. Methods : Cytotoxic activity of IJHT and its components on RAW 264.7 cells was using 5-(3-caroboxymeth-oxyphenyl)-2H-tetra-zolium inner salt (MTS) assay. The nitric oxide (NO) production was measured by Griess reagent system. And proinflammatory cytokines were measured by ELISA kit. The levels of inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) expression were detected by western blot. Results : IJHT and its components significantly inhibited the LPS-induced NO production and iNOS expression accompanied by an attenuation of tumor necrosis factor-alpha (TNF-${\alpha}$), interleukin-6 (1L-6), IL-$1{\beta}$ and monocyte chemoattractant protein-1 (MCP-1) formation in macrophages. Conclusions : IJHT and its components inhibit LPS-induced inflammation via decreasing cytokines production. These results indicate that IJHT and its components have potential as an anti-inflammation and anti-artherosclerosis agent.