• Journal of Life Science
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• v.17 no.2 s.82
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• pp.235-240
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• 2007

AvrRpt2 protein triggers hypersensitive response (HR) and strong disease resistance when it is translocated from a bacterial pathogen Pseudomonas sp. to host plant cells containing a cognate RPS2 resistance protein through Type III Secretion System (TTSS). However, AvrRpt2 protein can function as the effector that suppresses a basal defense and enhances the disease symptom when functional RPS2 resistance protein is absent in the infected plant cells. Using Affymetrix Arabidopsis DNA chip, we found that many genes were specifically regulated by AvrRpt2 protein in the rps2 Arabidopsis mutant. Here, we showed that expression of AtERF11 that is known as a member of B1a subcluster of AP2/ERF transcription factor family was down regulated specifically by AvrRpt2. To determine its function in plant resistance, we also generated the Arabidopsis thaliana transgenic plants constitutively overexpressing AtERF11 under CaMV 355 promoter, which conferred an enhanced resistance against a bacterial pathogen, Pseudomonas syringae pv. tomato DC3000. Thus, these results collectively suggest that AtERF11 plays a role as a positive regulator for disease resistance against biotrophic bacterial pathogen in plant.

• Journal of Life Science
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• v.28 no.2
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• pp.207-215
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• 2018

Inflammatory response and oxidative stress play critical roles in the development and progression of many human diseases. Therefore, a great deal of attention has been focused on finding functional materials that can control inflammation and oxidative stress simultaneously. The purpose of this study was to investigate the effects of Socheongja and Socheong 2, Korean black seed coat soybean varieties, on the inflammatory and oxidative stress induced by lipopolysaccharide (LPS) in RAW 264.7 macrophages. Our data indicated that the extracts of Socheongja (SCJ) and Socheong 2 (SC2) significantly suppressed LPS-induced production of nitrite oxide (NO) and prostaglandin $E_2$, key pro-inflammatory mediators, by suppressing the expression of inducible NO synthase and cyclooxygenase-2. It was also found that SCJ and SC2 reduced the LPS-induced secretion of pro-inflammatory cytokines, such as tumor necrosis $factor-{\alpha}$ and $interleukin-1{\beta}$, which was concomitant with a decrease in the protein levels. In addition, SCJ and SC2 markedly diminished LPS-stimulated intracellular reactive oxygen species accumulation, and effectively enhanced nuclear factor erythroid 2-related factor 2 (Nrf2) and heme oxygenase (HO)-1 expression. Furthermore, LPS-induced activation of mitogen-activated protein kinases (MAPKs) was abrogated by SCJ and SC2. Taken together, these data suggest that SCJ and SC2 may offer protective roles against LPS-induced inflammatory and oxidative responses in RAW 264.7 macrophages through attenuating MAPKs pathway, and these effects are mediated, at least in part, through activating Nrf2/HO-1 pathway. Given these results, we propose that SCJ and SC2 have therapeutic potential in the treatment of inflammatory and oxidative disorders caused by over-activation of macrophages.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.28 no.5
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• pp.375-395
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• 2006

Purpose: Lingual nerve (LN) damage may be caused by either tumor resection or injury such as wisdom tooth extraction, Although autologous nerve graft is sometimes used to repair the damaged nerve, it has the disadvantage of necessity of another operation for nerve harvesting. Moreover, the results of nerve grafting is not satisfactory. The nerve growth factor (NGF) is well-known to play a critical role in peripheral nerve regeneration and its local delivery to the injured nerve has been continuously tried to enhance nerve regeneration. However, its application has limitations like repeated administration due to short half life of 30 minutes and an in vivo delivery model must allow for direct and local delivery. The aim of this study was to construct a well-functioning $rhNGF-{\beta}$ adenovirus for the ultimate development of improved method to promote peripheral nerve regeneration with enhanced and extended secretion of hNGF from the injured nerve by injecting $rhNGF-{\beta}$ gene directly into crush-injured LN in rat model. Materials and Methods: $hNGF-{\beta}$ gene was prepared from fetal brain cDNA library and cloned into E1/E3 deleted adenoviral vector which contains green fluorescence protein (GFP) gene as a reporter. After large scale production and purification of $rhNGF-{\beta}$ adenovirus, transfection efficiency and its expression at various cells (primary cultured Schwann cells, HEK293 cells, Schwann cell lines, NIH3T3 and CRH cells) were evaluated by fluorescent microscopy, RT-PCR, ELISA, immunocytochemistry. Furthermore, the function of rhNGF-beta, which was secreted from various cells infected with $rhNGF-{\beta}$ adenovirus, was evaluated using neuritogenesis of PC-12 cells. For in vivo evaluation of efficacy of $rhNGF-{\beta}$ adenovirus, the LNs of 8-week old rats were exposed and crush-injured with a small hemostat for 10 seconds. After the injury, $rhNGF-{\beta}$ adenovirus($2{\mu}l,\;1.5{\times}10^{11}pfu$) or saline was administered into the crushed site in the experimental (n=24) and the control group (n=24), respectively. Sham operation of another group of rats (n=9) was performed without administration of either saline or adenovirus. The taste recovery and the change of fungiform papilla were studied at 1, 2, 3 and 4 weeks. Each of the 6 animals was tested with different solutions (0.1M NaCl, 0.1M sucrose, 0.01M QHCl, or 0.01M HCl) by two-bottle test paradigm and the number of papilla was counted using SEM picture of tongue dorsum. LN was explored at the same interval as taste study and evaluated electro-physiologically (peak voltage and nerve conduction velocity) and histomorphometrically (axon count, myelin thickness). Results: The recombinant adenovirus vector carrying $rhNGF-{\beta}$ was constructed and confirmed by restriction endonuclease analysis and DNA sequence analysis. GFP expression was observed in 90% of $rhNGF-{\beta}$ adenovirus infected cells compared with uninfected cells. Total mRNA isolated from $rhNGF-{\beta}$ adenovirus infected cells showed strong RT-PCR band, however uninfected or LacZ recombinant adenovirus infected cells did not. NGF quantification by ELISA showed a maximal release of $18865.4{\pm}310.9pg/ml$ NGF at the 4th day and stably continued till 14 days by $rhNGF-{\beta}$ adenovirus infected Schwann cells. PC-12 cells exposed to media with $rhNGF-{\beta}$ adenovirus infected Schwann cell revealed at the same level of neurite-extension as the commercial NGF did. $rhNGF-{\beta}$ adenovirus injected experimental groups in comparison to the control group exhibited different taste preference ratio. Salty, sweet and sour taste preference ratio were significantly different after 2 weeks from the beginning of the experiment, which were similar to the sham group, but not to the control group.

• Development and Reproduction
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• v.13 no.4
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• pp.207-215
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• 2009

Numerous factors can affect the activities of hypothalamus-pituitary-gonad (HPG) hormonal axis, resulting in alteration of reproductive capacity or status such as onset of puberty and menopause. Soon after the finding of leptin, a multifunctional hormone secreted from adipocytes, a close relationship between reproduction and body energy balance have been manifested. Ghrelin, another multifunctional hormone from gastrointestinal tract, is an endogenous ligand of growth hormone secretagogue receptor (GHSR), and is thought to be a counterpart of leptin in the regulation of energy homeostasis. As expected, ghrelin can also modulate the reproductive capacity through the modulation of activities of HPG axis. This paper summarizes the current knowledge on the discovery, gene structures, tissue distribution and roles of ghrelin and GHSRs in mammalian reproduction in particular modulation of reproductive hormone secretion in HPG axis. Like POMC gene expression in pituitary gland, preproghrelin gene can generate a complex repertoire of transcripts which further undergo alternative splicing and posttranslational modifications. Concerning the roles of preproghrelin gene products in the control of body physiology except energy homeostasis, limited knowledge is available so far. Several lines of evidence, however, show the interplay of ghrelin between metabolism and reproduction. In rat and human, the distribution of ghrelin receptor GHSRs (GHSR1a and GHSR1b) has been confirmed not only in the hypothalamus and pituitary which were originally postulated as target of ghrelin but also in the testis and ovary. Expression of the preproghrelin gene in the brain and gonads was also verified, suggesting the local role (s) of ghrelin in HPG axis. Ghrelin might play a negative modulator in the secretions of hypothalamic GnRH, pituitary gonadotropins and gonadal steroids though the action on pituitary is still questionable. Recent studies suggest the involvement of ghrelin in regulation of puberty onset and possibly of menopause entry. It is now evident that ghrelin is a crucial hormomal component in 'brain-gut' axis, and is a strong candidate links between metabolism and reproduction. Opposite to that for leptin, ghrelin signaling is likely representing the 'hunger' state of body energy balance and is necessary to avoid the energy investment into reproduction which has not a top priority in maintaining homeostasis. Further researches are needed to gain a deep insight into the more precise action mechanism and role of ghrelin in reproduction, and to guarantee the successful biomedical applications.

• Tuberculosis and Respiratory Diseases
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• v.44 no.3
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• pp.601-610
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• 1997

Background : Monocytes/macrophages play a central role in determining the host response during Gram-negative infection through secretion of a variety of mediators after stimulation of LPS. Even though cytokine production has been shown to play an important role in host defense during sepsis, cytokine release may also lead to tissue injury. Thus, regulation of macrophage response to LPS is critical for host survival during Gram-negative sepsis. In animals exposed to nonlethal doses of endotoxin, a characteristic hyporesponsiveness to subsequent administration of endotoxin has been observed. This phenomenon was known as 'LPS tolerance'. However, little information is available regarding the underlying mechanism of LPS tolerance. Method : Peripheral blood monocyte(PBMC) was isolated from peripheral blood of normal volunteers by adhesion purification method. To evaluate the conditions to obtain LPS tolerance, preculture was carried out with LPS at 10ng/ml for 24 hours. For stimulation, culture plates were washed two times and were stimulated with LPS at $1{\mu}g/ml$ for 4, 6 and 26 hours. To assess the underlying mechanisms of LPS tolerance, autologous serum, PMA, anti-CD14 Ab, Indomethacin or $PGF_2$ were added to preculture solution respectively. Cytokine concentrations in culture supernatants were measured using ELISA for TNF-$\alpha$ and IL-8 and mRNA of TNF-$\alpha$ and IL-8 were determined by Northern blot analysis. Results : The exposure of PBMC to low dose of LPS suppressed the cytokine production and mRNA expression of TNF-$\alpha$, but not IL-8. Anti-CD14 Ab partially recovered production of TNF-$\alpha$ which was suppressed by preculture with low dose LPS. The preculture with PMA induces LPS tolerance, as preculture with low dose LPS. Conclusion : LPS tolerance to TNF-$\alpha$ is regulated pretranslationally and is influenced by protein kinase C pathway and CD14.

• Microbiology and Biotechnology Letters
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• v.44 no.3
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• pp.236-245
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• 2016

This study investigated the anti-inflammatory effects of wheat germ oil (WGO) on RAW 264.7 cells. It was shown that WGO had no cytotoxicity against the treated cells or negative effect on their proliferation. WGO suppressed nitric oxide (NO) secretion considerably and had inhibitory effects on the production of LPS-induced NO and pro-inflammatory cytokines (IL-6, TNF-α, and IL-1β). In particular, the IL-6 and TNF-α inhibition activities were over 90% at 100 μg/ml concentration of the oil. WGO also inhibited the LPS-induced expression of cyclooxygenase-2, inducible nitric oxide synthase, and nuclear factor-kappa B (NF-κB), and reduced the expression of phosphorylated ERK and JNK. Moreover, the croton-oil-induced edema in mouse ears was reduced by WGO, and no mortalities occurred in mice administered 5,000 mg/kg body weight of WGO over a 2-week observation period. In conclusion, these results provide evidence for the anti-inflammatory effect of WGO that likely occurs via modulation of NF-κB and the JNK/ERK MAPK signaling pathway.

• Journal of the Korean Society of Food Science and Nutrition
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• v.42 no.5
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• pp.690-696
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• 2013

The objective of this study was to investigate the protective effect of extracts from Canavalia gladiata (CGE) on gastric inflammation induced by alcohol treatment in SD rats. Rats were divided into four groups: G1 (normal group), G2 (gastric inflammation induced by alcohol), G3 (gastric inflammation induced by alcohol with lansoprazole pretreatment), G4 (gastric inflammation induced by alcohol with 250 mg/kg b.w. CGE pretreatment), G5 (gastric inflammation induced by alcohol with 500 mg/kg b.w. CGE pretreatment). After the oral administration of 40% alcohol and samples for seven days, acute gastritis was induced with 70% alcohol and 0.15 M HCl. After 1 h of alcohol administration, the animals were sacrificed. Groups pretreated with lansoprazole or CGE showed an attenuation of gastric mucosal injury, including decreases in sub-epithelial loss, hemorrhages, and gastric juice secretion induced by administration of alcohol. The oral administration of CGE (500 mg/kg b.w.) significantly decreased the levels of TBARS. To examine molecular factors that regulate inflammation, the protein expression of NF-${\kappa}B$ and COX-2 were measured through immuno-histochemistry. Compared with the normal group (G1), the expression of NF-${\kappa}B$ and COX-2 were clearly increased in G2. COX-2 and NF-${\kappa}B$ were expressed even higher in groups pretreated with CGE compared to G2. In conclusion, our data show that Canavalia gladiata has inhibitory and protective effects on gastric inflammation induced by alcohol treatment in SD rats.

• Tuberculosis and Respiratory Diseases
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• v.49 no.6
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• pp.703-714
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• 2000

Background : Surfactant protein A (SP-A) is important in the regulation of surfactant secretion, synthesis and recycling. SP-A has important roles in regulating surfactant metabolism as well as in determining surfactant's physical properties. Since systemic sepsis is one of the common causes of acute respiratory distress syndrome (ARDS) and abnormalities in surfactant function have been described in ARDS, the authors investigated the effects of endotoxemia on the accumulation of mRNA encoding SP-A and SP-A protein content. Methods : Adult rats were given various doses of intraperitoneal endotoxin from Salmonella enteritidis and sacrificed at different times. SP-A mRNA was measured by filter hybridization method. Lung SP-A protein content was determined by double sandwich ELISA assay using a polyclonal antiserum raised in rabbits against purified rat SP-A. Results : 1) The accumulation of SP-A mRNA in the endotoxin treated group 24 hours after 2mg/kg and 5mg/kg endotoxin treatments was significantly increased 50.9% and 27.3%, respectively, compared to the control group (P<0.001, P<0.025). 2) The accumulation of SP-A mRNA 24 hours in the 5mg/kg endotoxin treated group was significantly increased by 26.5% compared to the control group (P<0.01). 3) Total amount of lung SP-A was not altered at 24 hours by various doses of treatment. Total lung SP-A content 144 hours after endotoxin administration was significantly decreased by 51.4% compared to the control group (P<0.01). Conclusions : The specific regulation of SP-A by various time course in vivo is evident. The late decline in SP-A protein content was unexpected and suggests that SP-A may be differentially regulated during lung inflammation. The functional significance of these alterations remains to be clarified.

• Journal of Life Science
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• v.28 no.12
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• pp.1416-1423
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• 2018

With strong biotin binding affinity ($K_D=10^{-14}M$), the tetrameric feature of streptavidin could be used to increase the antigen binding activity of a camel heavy chain (VHH) antibody through their fusion, here stained with biotinylated horseradish peroxidase and subsequent immunoassays ELISA and Western blot analysis. For this application, we cloned the streptavidin gene amplified from the Streptomyces avidinii chromosome by PCR, and this was fused to the gene of the 8B9 VHH antibody which is specific to green fluorescent protein (GFP) antigens. To express a soluble fusion protein in Escherichia coli, we used the pUC119 plasmid-based expression system which uses the lacZ promoter for induction by IPTG, the pelB leader sequence at the N-terminus for secretion into the periplasmic space, and six polyhistidine tags at the C-terminus for purification of the expressed proteins using an $Ni^+$-NTA-agarose column. Although streptavidin is toxic to E. coli because of its strong biotin binding property, this soluble fusion protein was expressed successfully. In SDS-PAGE, the size of the purified fusion protein was 122.4 kDa in its native condition and 30.6 kDa once denatured by boiling, suggesting the tetramerization of the monomeric subunit by non-covalent association through the streptavidin moiety fusing to the 8B9 VHH antibody. In addition, this fusion protein showed biotin binding activity similar to streptavidin as well as GFP antigen binding activity through both ELISA and Western blot analysis. In conclusion, the protein resulting from the fusion of an 8B9 VHH antibody with streptavidin was successfully expressed and purified as a soluble tetramer in E. coli; it showed both biotin and GFP antigen binding activity suggesting the possible production of a tetrameric and bifunctional VHH antibody.

• Journal of Life Science
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• v.31 no.11
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• pp.987-994
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• 2021

Our previous studies have reported that antimicrobial peptides (AMPs) derived from the larvae of white-spotted flower chafer (Protaetia brevitarsis seulensis) exert anti-inflammatory and neuroprotective activities. This study explored the anti-inflammatory effects of protaetiamycine 9 (CVLKKAYFLTNLKLRG-NH₂), a novel AMP, derived from P. b. seulensis against lipopolysaccharide (LPS)-mediated inflammatory response in RAW264.7 macrophage cells. Protaetiamycine 9 (25, 50, 75, and 100 ㎍/ml) did not cause cytotoxic effects against RAW264.7 cells. The RAW264.7 cells were pre-treated with various concentrations of protaetiamycine 9 (25-100 ㎍/ml) for 1 hr and then exposed to LPS (100 ng/ml) for 24 hr. Protaetiamycine 9 treatments decreased the LPS-induced secretion of inflammatory mediators, such as nitric oxide (NO), in a dose-dependent manner. Protaetiamycine 9 (25-100 ㎍/ml) effectively downregulated the LPS-induced increase in mRNA and the protein expression of inducible NO synthase (iNOS) and cyclooxygenase-2 (COX-2), which are involved in the production of inflammatory mediators. Protaetiamycine 9 also suppressed the production and gene expression of pro-inflammatory cytokines, including interleukin (IL)-6 and IL-1β, compared to the presence of LPS alone. Furthermore, protaetiamycine 9 inhibited the degradation of inhibitory kappa B alpha (IκB-α) and the phosphorylation of mitogen-activated protein kinases (MAPKs), such as extracellular signal-regulated kinase (ERK), c-Jun N-terminal kinase (JNK), and p38. In conclusion, these results suggest that protaetiamycine 9 exhibits LPS-mediated inflammatory responses by blocking IκB-α degradation and MAPK phosphorylation.