• Asian-Australasian Journal of Animal Sciences
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• v.28 no.4
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• pp.573-583
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• 2015

B-32 is one of a panel of monoclonal anti-idiotypic antibodies to growth hormone (GH) that we developed. To characterize and identify its potential role as a novel growth hormone receptor (GHR) agonist, we determined that B-32 behaved as a typical $Ab2{\beta}$ based on a series of enzyme-linked immunosorbent assay assays. The results of fluorescence-activated cell sorting, indirect immunofluorescence and competitive receptor binding assays demonstrated that B-32 specifically binds to the GHR expressed on target cells. Next, we examined the resulting signal transduction pathways triggered by this antibody in primary porcine hepatocytes. We found that B-32 can activate the GHR and Janus kinase (2)/signal transducers and activators of transcription (JAK2/STAT5) signalling pathways. The phosphorylation kinetics of JAK2/STAT5 induced by either GH or B-32 were analysed in dose-response and time course experiments. In addition, B32 could also stimulate porcine hepatocytes to secrete insulin-like growth factors-1. Our work indicates that a monoclonal anti-idiotypic antibody to GH (B-32) can serve as a GHR agonist or GH mimic and has application potential in domestic animal (pig) production.

• Asian-Australasian Journal of Animal Sciences
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• v.18 no.2
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• pp.165-169
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• 2005

This study was performed to offer effective basic data for selection and improvement of Korean dairy cattle through identifying distributional properties among candidate genes (bovine butyrophilin, signal transducers and activators of transcription 5a, and prolactin hormone). In this study, polymorphisms of candidate genes were identified and the relationships between loci and production traits of each gene were analyzed using frozen semen of Holstein bulls (19 proven and 77 candidates). In butyrophilin (BTN) locus, polymorphisms information contents (PIC) value of BTN2 (0.372) was higher than those of others (BTN1; 0.155, BTN3; 0.254, BTN4; 0.169). As a result of analysis of genotyping STAT5a, using single stranded conformational polymorphism (SSCP) method and microsatellite locus, PIC values were 0.189 and 0.457, respectively. And PIC value of prolactin hormone gene was 0.176. In the relationships between genotypes and production traits, BTN3 was associated with 305-day production traits (p<0.05). PTAs for B allele were such as 110.43, 88.28 and 75.25 in BTN1, 3, 4 and these values were higher than those of A allele, but in the case of BTN2, A allele with 154.19 was higher than that of B allele. The results obtained from using candidate genes may be used as an useful index for the genetic improvement of dairy cattle population in Korea, and further studies are needed.

• Asian-Australasian Journal of Animal Sciences
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• v.15 no.7
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• pp.938-943
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• 2002

This study was perfonned to detect polymorphisms of the two candidate genes, bovine BTN (Butyrophilin) and ST AT5a (Signal Transducers and Activators of Transcription) gene using 98 Holstein bulls' frozen semen, and to offer the basic information for QTL (Quantitative Trait Loci) analysis. Each BTN PCR product was digested with endonuclease restriction enzyme. The digested fragments of four BTN PCR products were observed as follows: 316,280, and 162 bp in BTN1, 568, 305 and 263 bp in BTN2, 576, 332, and 244 bp in BTN3, and 573, 291, and 282 bp in BTN4, respectively. The gene frequencies of A and B allele in four BTN loci were as follows: 0.8980 and 0.1020 in BTN1, 0.5510 and 0.4490 in BTN2, 0.8163 and 0.1837 in BTN3, and 0.8875 and 0.1122 in BTN4, respectively. And three genotypes (homotypel, heterotype, and homotype2) for STAT5a were observed by SSCP (single stranded conformational polymorphism) method and the genotype frequencies are 78.57%, 19.39%, and 2.04%, respectively. The PlC (Polymorphism Information Content) value and heterozygosity of four BTN loci were as follows: 0.1695 and 0.1870 in BTN1, 0.3713 and 0.4927 in BTN2, 0.2549 and 0.2999 in BTN3, and 0.1794 and 0.1992 in BTN4, respectively. Comparing with the reported data, PlC value of BTN2 might have the possibility to be useful marker. Other BTN loci indicated skewed allele distribution.

• Natural Product Sciences
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• v.23 no.1
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• pp.1-4
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• 2017

Sinensetin, a pentamethoxyflavone, is known to exert various pharmacological activities including anti-angiogenesis, anti-diabetic and anti-inflammatory activities. However, its effects on the human mast cell - 1 (HMC-1) mediated inflammatory mechanism remain unknown. To explore the mediator and cellular inflammatory response of sinensetin, we examined its influence on phorbol 12-myristate 13-acetate (PMA) plus A23187 induced inflammatory mediator production in a human mast cell line. In this study, interleukin (IL)-6 production was measured using the enzyme-linked immunosorbent assay and reverse transcription polymerase chain reaction. Sinensetin inhibited PMA plus A23187 induced IL-6 production in a dose-dependent manner as well as IL-4, IL-5 and IL-8 mRNA expression. Furthermore, sinensetin inhibited signal transducer and activator of transcription 3 (STAT3) phosphorylation, suggesting that sinensetin inhibits the production of inflammatory mediators by blocking STAT3 phosphorylation. Moreover, sinensetin was found to inhibit nuclear factor kappa B activation. These findings suggest that sinensetin may be involved in the regulation of mast cell-mediated inflammatory responses.

• BMB Reports
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• v.34 no.5
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• pp.484-488
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• 2001

STATs are proteins with a dual function: signal transducers in the cytoplasm and transcriptional activators in the nucleus. Among the six known major STATs (STAT1-6), STAT3 has been implicated in the widest range of signaling pathways that regulate cell growth and differentiation. As a part of our on-going investigation on the pleiotropic functions of STAT proteins, we examined the role of STAT3 as a molecular adaptor that links diverse cell growth signaling pathways. We observed that STAT3 can be specifically activated by multiple cytokines, such as IL-3, in transformed fibroblasts and IL-4 or IFN-$\gamma$ in primary immune cells, respectively. The selective activation of STAT3 in H-ras-transformed NIH3T3 cells is associated with an increased expression of phosphoserioe STAT3 in these cells, compared to the parental cells. Notably phosphoresine-STAT3 interacts with oncogenic ras, shown by immunoprecipitation and Western blots. The results suggest the role of STAT3 in rasinduced cellular transformation as a molecular adaptor linking the Jak/STAT and Ras/MAPK pathways. In primary immune cells, IL-4 and IFN-$\gamma$ each induced (in addition to the characteristic STAT6 and STAT1 homodimers) the formation of STAT3-containing complexes that bind to GAS probes, which correspond to the $Fe{\varepsilon}$ Rll and $Fe{\gamma}$ RI promoter sequences, respectively. Since IL-4 and IFN-$\gamma$ are known to counter-regulate the expression of these genes, the ability of STAT3 to form heterodimeric complexes with STAT6 or STAT1 implies its role in the fine-tuned control of genes that are regulated by IL-4 and IFN-$\gamma$.

• Biomolecules & Therapeutics
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• v.23 no.3
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• pp.238-244
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• 2015

Macrophage-derived chemokine, C-C motif chemokine 22 (MDC/CCL22), is one of the inflammatory chemokines that controls the movement of monocytes, monocyte-derived dendritic cells, and natural killer cells. Serum and skin MDC/CCL22 levels are elevated in atopic dermatitis, which suggests that the chemokines produced from keratinocytes are responsible for attracting inflammatory lymphocytes to the skin. A major signaling pathway in the interferon-${\gamma}$ (IFN-${\gamma}$)-stimulated inflammation response involves the signal transducers and activators of transcription 1 (STAT1). In the present study, we investigated the anti-inflammatory effect of dieckol and its possible action mechanisms in the category of skin inflammation including atopic dermatitis. Dieckol inhibited MDC/CCL22 production induced by IFN-${\gamma}$ (10 ng/mL) in a dose dependent manner. Dieckol (5 and $10{\mu}M$) suppressed the phosphorylation and the nuclear translocation of STAT1. These results suggest that dieckol exhibits anti-inflammatory effect via the down-regulation of STAT1 activation.

• Journal of Life Science
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• v.21 no.1
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• pp.141-145
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• 2011

Actinomycin D is a natural antibiotic that is used in anti-cancer chemotherapy and is known as a transcription inhibitor. Interestingly, actinomycin D induces phosphorylation of signal transducers and activators of transcription 3 (STAT3) in renal cancer Caki cells. In this study, we examined the molecular mechanism of actinomycin D-induced STAT3 phosphorylation. Treatment with actinomycin D induced phosphorylation of STAT3 (Tyr705) in a dose- and time-dependent manner. However, actinomycin D did not induce phosphorylation of STAT3 (Ser727), STAT1 (Tyr701) and STAT1 (Ser727). Moreover, actinomycin D-induced STAT3 phosphorylation was caused by decreased protein and mRNA levels of SOCS3, but not by JAK2 and SHP-1. In addition, other transcription inhibitor (5,6-dichloro-1-b-D-ribofuranosyl benzimidazole; DRB) also induced phosphorylation of STAT3 (Tyr705). Taken together, the present study demonstrates that transcriptional inhibitors (actinomycin D and DRB) induce phosphorylation of STAT3 (Tyr705) in Caki cells by down-regulation of SOCS3.

• Journal of Physiology & Pathology in Korean Medicine
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• v.23 no.5
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• pp.986-992
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• 2009

Type I interferons (IFNs) are critical mediators of the innate immune system to defend viral infection. Interferon regulatory factor (IRF) and signal transducer and activator of transcription (STAT) play critical roles in type I IFN production in response to viral infection. Luteolin is natural polyphenolic compounds that have anti-inflammatory, cytoprotective and anti-carcinogenic effects. However, the mechanism of action and impact of luteolin on innate immunity is still unknown. In this study, we examined the effects of luteolin on the lipopolysacchride (LPS)-induced inflammatory responses. Luteolin inhibited Type I IFNs expression of mRNA and increased interleukin(IL)-10 expression of mRNA. Next, we examined the protective effects of IL-10 using IL-10 neutralizing antibody (IL-10NA). Blockade of IL-10 action didn't cause a significant reduction of Type I IFNs than LPS-induced luteolin pretreatment. Pretreatment of luteolin inhibited the level of IRF-1, and IRF-7 mRNA and the nuclear translocation of IRF-3. Also, luteolin reduced the activation of STAT - 1, 3. Theses results suggest that luteolin inhibits LPS-induced the production of Type I IFNS by both IRFs and STATs not IL-10 and may be a beneficial drug for the treatment of inflammatory disease.