• The Korean Journal of Physiology and Pharmacology
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• v.19 no.1
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• pp.29-34
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• 2015

Fucoidan, a fucose-rich sulfated polysaccharide derived from brown seaweed in the class Phaeophyceae, has been widely studied for its possible health benefits. However, the potential of fucoidan as a possible treatment for hyperpigmentation is not fully understood. This study investigated the effects of fucoidan on melanogenesis and related signaling pathways using Mel-Ab cells. Fucoidan significantly decreased melanin content. While fucoidan treatment decreased tyrosinase activity, it did not do so directly. Western blot analysis indicated that fucoidan downregulated microphthalmia-associated transcription factor and reduced tyrosinase protein expression. Further investigation showed that fucoidan activated the extracellular signal-regulated kinase (ERK) pathway, suggesting a possible mechanism for the inhibition of melanin synthesis. Treatment with PD98059, a specific ERK inhibitor, resulted in the recovery of melanin production. Taken together, these findings suggest that fucoidan inhibits melanogenesis via ERK phosphorylation.

• The Plant Pathology Journal
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• v.17 no.2
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• pp.67-70
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• 2001

Medicago truncatula is a diploid legume plant related to the forage crop alfalfa. Recently, it has been chosen as a model species for genomic studies due to its small genome, self-fertility, short generation time, and high transformation efficiency. M. truncatula engages in symbiosis with nitrogen-fixing soil bacterium Rhizobium meliloti. M. truncatula mutants that are defective in nodulation and developmental processes have been generated. Some of these mutants exhibited altered phenotypes in symbiotic responses such as root hair deformation, expression of nodulin genes, and calcium spiking. Thus, the genes controlling these traits are likely to encode functions that are required for Nod-factor signal transduction pathways. To facilitate genome analysis and map-based cloning of symbiotic genes, a bacterial artificial chromosome library was constructed. An efficient polymerase chain reaction-based screening of the library was devised to fasten physical mapping of specific genomic regions. As a genomics approach, comparative mapping revealed high levels of macro- and microsynteny between M. truncatula and other legume genomes. Expressed sequence tags and microarray profiles reflecting the genetic and biochemical events associated with the development and environmental interactions of M. truncatula are assembled in the databases. Together, these genomics programs will help enrich our understanding of the legume biology.

• Archives of Pharmacal Research
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• v.22 no.2
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• pp.130-136
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• 1999

Mouse guanylate-binding protein 3 (mGBP3) is a 71-kDa GTPase which belongs to GTP-binding protein family. The present study showed that the expression of mGBP3 transcript was readily induced in a dose dependent fashion in the macrophage cell line RAW264.7 treated with either $interferon-{\gamma} (IFN-\gamma)$ or lipopolysaccaride (LPS). The expression of mGBP3 protein was also apparent by 4 and 6 h after the treatment of cells with IFN-\gamma (100 U/ml) or LPS ($1{\mu}g/ml$) , and remained at palteau for at least 24 h. Cycloheximide ($10{\mu}g/ml$) had no effect on the $IFN-\gamma-$ or LPS-induced mGBP3 expression, suggesting that the mGBP3 induction did not require further protein synthesis. Interestingly, a protein kinase C (PKC) inhibitor staurosporine (50 nM) abolished the induction of mGBP3 expression by LPS, but not by $IFN-{\gamma}$. These findings suggest that mGBP3 may be involved in the macrophage activation process and both IFN-\gamma and LS induce the mGBP3 expression through distinct signal transduction pathways.

• Journal of Plant Biotechnology
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• v.45 no.4
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• pp.315-321
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• 2018

Molecular and functional characterization of proteins and their levels is of great interest in understanding the mechanism of diverse cellular processes. In this study, we report on the convenient Escherichia coli-based protein expression system that allows recombinant of soluble proteins expression and cytosolic domain of membrane-localised kinases, followed by the detection of autophosphorylation activity in protein kinases. This approach is applied to regulatory proteins of Arabidopsis thaliana, including 14-3-3, calmodulin, calcium-dependent protein kinase, TERMINAL FLOWER 1(TFL1), FLOWERING LOCUS T (FT), receptor-like cytoplasmic kinase and cytoplasmic domain of leucine-rich repeat-receptor like kinase proteins. Our Western blot analysis which uses phospho-specific antibodies showed that five putative LRR-RLKs and two putative RLCKs have autophosphorylation activity in vitro on threonine and/or tyrosine residue(s), suggesting their potential role in signal transduction pathways. Our findings were also discussed in the broader context of recombinant expression and biochemical analysis of soluble and membrane-localised receptor kinases in microbial systems.

• Journal of Microbiology and Biotechnology
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• v.28 no.12
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• pp.2121-2132
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• 2018

Abnormal melanin synthesis results in several hyperpigmentary disorders such as freckles, melanoderma, age spots, and other related conditions. In this study, we investigated the anti-melanogenic effects of an extract from the microalgae Chlamydomonas reinhardtii (CE) and potential mechanisms responsible for its inhibitory effect in B16F10, normal human epidermal melanocyte cells, and human skin-equivalent models. The CE extract showed significant dose-dependent inhibitory effects on ${\alpha}$-melanocyte-stimulating, hormone-induced melanin synthesis in cells. Additionally, the CE extract exhibited suppressive effects on the mRNA and protein expression of microphthalmia-associated transcription factor, tyrosinase, tyrosinase-related protein-1, and tyrosinase-related protein-2. The CE extract also inhibited the phosphorylation of protein kinase A and extracellular signal-related kinase, which function as upstream regulators of melanogenesis. Using a three-dimensional, reconstructed pigmented epidermis model, the CE-mediated, anti-pigmentation effects were confirmed by Fontana-Masson staining and melanin content assays. Taken together, CE extract can be used as an anti-pigmentation agent.

• Asian-Australasian Journal of Animal Sciences
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• v.32 no.3
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• pp.309-319
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• 2019

Phytochemicals which exist in various plants and fungi are non-nutritive compounds that exert numerous beneficial bioactive actions for animals. In recent years following the restriction of antibiotics, phytochemicals have been regarded as a primal selection when dealing with the challenges during the producing process in the poultry industry. The selected fast-growing broiler breed was more fragile when confronting the stressors in their growing environments. The disruption of oxidative balance that impairs the production performance in birds may somehow be linked to the immune system since oxidative stress and inflammatory damage are multi-stage processes. This review firstly discusses the individual influence of oxidative stress and inflammation on the poultry industry. Next, studies related to the application of phytochemicals or botanical compounds with the significance of their antioxidant and immunomodulatory abilities are reviewed. Furthermore, we bring up nuclear factor (erythroid-derived 2)-like 2 (Nrf2) and nuclear factor kappa B ($NF-{\kappa}B$) for they are respectively the key transcription factors involved in oxidative stress and inflammation for elucidating the underlying signal transduction pathways. Finally, by the discussion about several reports using phytochemicals to regulate these transcription factors leading to the improvement of oxidative status, heme oxygenase-1 gene is found crucial for Nrf2-mediated $NF-{\kappa}B$ inhibition.

• Journal of Pharmacopuncture
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• v.22 no.2
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• pp.55-67
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• 2019

The incidences of cancer are continuously increasing worldwide, affecting life of millions of people. Several factors associated with the internal and external environment are responsible for this deadly disease. The key internal determinants like abnormal hormonal regulation, genetic mutations and external determinants such as lifestyle and occupational factors enhances onset of cancer. From the ancient time, plants were remained as the most trusted source of medicine for the treatment of diverse disease conditions. Extensive studies have been performed for the discovery of effective anticancer agent from the plant and still it is going on. Pentacyclic triterpenoids are biologically active phytochemicals having a different range of activities such as anti-inflammatory, hepatoprotective, anti-hypertensive, antiulcerogenic and anti-tumor. These compounds generally contain ursane, oleanane, lupane and friedelane as a chief skeleton of pentacyclic triterpenoids which are generally present in higher plants. Isoprene unit, phytochemical, with good antitumor/anticancer activity is required for the biosynthesis of pentacyclic triterpenoids. Mechanisms such as cytotoxicity, DNA polymerase inhibition, regulation of apoptosis, change in signal transductions, interfere with angiogenesis and dedifferentiation, antiproliferative activity and metastasis inhibition are might be responsible for their anticancer effect. Present review spotlights diverse targets, mechanisms and pathways of pentacyclic triterpenoids responsible for anticancer effect.

• Journal of Microbiology and Biotechnology
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• v.32 no.2
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• pp.205-211
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• 2022

Probiotics can effectively modulate host immune responses and prevent gastrointestinal diseases. The objective of this study was to investigate the probiotic characteristics of Lactobacillus brevis KU15152 isolated from kimchi and its protective potential against intestinal inflammation induced by Staphylococcus aureus lipoteichoic acid (aLTA). L. brevis KU15152 exhibited a high survival rate in artificial gastric and bile environments. Additionally, the adhesion capability of the strain to HT-29 cells was higher than that of L. rhamnosus GG. L. brevis KU15152 did not produce harmful enzymes, such as β-glucuronidase, indicating that it could be used as a potential probiotic. The anti-inflammatory potential of L. brevis KU15152 was determined in HT-29 cells. Treatment with L. brevis KU15152 suppressed the production of interleukin-8 without inducing significant cytotoxicity. The downregulatory effects of L. brevis KU15152 were involved in the suppression of nuclear factor-kappa B activation mediated by the extracellular signal-regulated kinase and Akt signaling pathways. Collectively, these data suggest that L. brevis KU15152 can be used in developing therapeutic and prophylactic products to manage and treat aLTA-induced intestinal damage.

• Biomolecules & Therapeutics
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• v.31 no.1
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• pp.48-58
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• 2023

Interferon regulatory factor 3 (IRF3) integrates both immunological and non-immunological inputs to control cell survival and death. Small GTPases are versatile functional switches that lie on the very upstream in signal transduction pathways, of which duration of activation is very transient. The large number of homologous proteins and the requirement for site-directed mutagenesis have hindered attempts to investigate the link between small GTPases and IRF3. Here, we constructed a constitutively active mutant expression library for small GTPase expression using Gibson assembly cloning. Small-scale screening identified multiple GTPases capable of promoting IRF3 phosphorylation. Intriguingly, 27 of 152 GTPases, including ARF1, RHEB, RHEBL1, and RAN, were found to increase IRF3 phosphorylation. Unbiased screening enabled us to investigate the sequence-activity relationship between the GTPases and IRF3. We found that the regulation of IRF3 by small GTPases was dependent on TBK1. Our work reveals the significant contribution of GTPases in IRF3 signaling and the potential role of IRF3 in GTPase function, providing a novel therapeutic approach against diseases with GTPase overexpression or active mutations, such as cancer.

• CELLMED
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• v.13 no.6
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• pp.7.1-7.6
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• 2023

Raphanus sativus L. has been reported to have anti-inflammatory and anti-tumor activity. However, the anti-inflammatory effect and mechanism of action of the Raphanus sativus L. seeds (RSS) with or without oil are still unknown. This study was undertaken to investigate the in-vitro anti-inflammatory effect with or without oil in the RSS on RAW 264.7 cells stimulated by lipopolysaccharide (LPS). Results showed the suppressed LPS-induced secretion of pro-inflammatory mediators such as nitric oxide (NO), inflammatory cytokine (IL-6, TNF-α). Additionally, a decrease in protein expression of iNOS was observed, but nuclear translocation of NF-κB p65 was not inhibited. To elucidate the underlying mechanism of the anti-inflammatory effect of RSS, the involvement of mitogen-activated protein kinase (MAPK) signaling pathways was examined. We also found that RSS blocked LPS-induced phosphorylation of c-Jun N-terminal kinase/stress-activated protein kinase (JNK) signaling but did not affect the phosphorylation of p38 MAPK and extracellular signal-regulated kinase (ERK) 1/2. These results suggest that RSS may have potential as an anti-inflammatory agent through the inhibition of LPS-induced inflammatory cytokine production via regulation of the JNK pathway.