• Korean Journal of Fisheries and Aquatic Sciences
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• v.50 no.3
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• pp.302-310
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• 2017

Interferon regulatory factor 8 (IRF8) is essential for the development of B and T cells, as well as for the activity of dendritic cells and macrophages. We performed molecular characterization of IRF8 from rock fish, Sebastes schlegelii (Ss), and investigated the spatial and temporal profile of mRNA expression after challenge with lipopolysaccharide (LPS), polyinosinic:polycytidylic acid (poly I:C), or Streptococcus iniae. The full-length cDNA sequence of SsIRF8 was 1,657 bp, containing an ORF of 1,266 bp. The gene had a predicted molecular mass of 47.7 kDa and an isoelectric point of 5.99. The amino acid sequence coded by this gene showed the highest degree of identity (90.8%) and similarity (96.2%) with IRF8 from Oplegnathus fasciatus. The SsIRF8 mRNA was expressed ubiquitously, at varying levels, with the highest level of expression observed in the spleen. To confirm the role of SsIRF8 in mediating the immune response, we measured SsIRF8 mRNA expression in the splenic tissue at different time points after injection with LPS, poly I:C, or S. iniae. The qRT-PCR results showed that SsIRF8 mRNA expression in the poly I:C-injected group was highly upregulated 6 hr after exposure (P<0.05). Expression of SsIRF8 mRNA in the S. iniae-injected group peaked at 24 hr. These results suggest that SsIRF8 might be important in regulating the strength of the rockfish immune response to immunostimulatory agents.

• Journal of Life Science
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• v.27 no.8
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• pp.879-887
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• 2017

It is well established that brain-derived neurotrophic factor (BDNF) is expressed not only in the brain but also in skeletal muscle, and is required for normal neuromuscular system function. Histone deacetylases (HDACs) and insulin-like growth factor-I (IGF-I) are potent regulators of skeletal muscle myogenesis and muscle gene expression, but the mechanisms of HDAC and IGF-I in skeletal muscle-derived BDNF expression have not been examined. In this study, we examined the effect of IGF-I and suberoylanilide hydroxamic acid (SAHA), a pan-HDAC inhibitor, on BDNF induction. Proliferating or differentiating C2C12 skeletal muscle cells were treated with increasing concentrations (0-50 ng/ml) of IGF-I in the absence or presence of $5{\mu}M$ SAHA for various time periods (3-24 hr). Treatment of C2C12 cells with IGF-I resulted in a dose- and time-dependent decrease in BDNF mRNA expression. However, inhibition of HDAC led to a significant increase in the expression of BDNF mRNA levels. In addition, immunocytochemistry revealed high BDNF protein levels in undifferentiated C2C12 skeletal muscle cells, whether untreated, IGF-I-treated, or exposed to SAHA. These results represent the first evidence that IGF-I can suppress the mRNA and protein expression of BDNF; conversely, SAHA attenuates the effects of IGF-I. Consequently, SAHA upregulates BDNF expression in C2C12 skeletal muscle cells.

• KSBB Journal
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• v.18 no.4
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• pp.329-334
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• 2003

The present study was aimed at investigating the regulatory mechanism in tissue-specific expression of insulin-like growth factor-I (IGF-I) gene. The expression of IGF-I gene was determined by a solution hybridization/RNase protection assay using total RNA prepared from rat liver or brain of various ages. The levels of IGF-I transcripts were increased in liver gradually after birth, but decreased in brain. By using an oligonucleotide (FRE) corresponding to the C/EBP binding site of the rat IGF-I exon 1, multiple forms of C/EBP${\alpha}$ and C/EBP${\beta}$ proteins, which have DNA-binding activity, were detected in the rat liver or brain. Western immunoblot and southwestern analyses show that p42$\^$C/EBP${\alpha}$/, p38$\^$C/EBP${\alpha}$/, p35$\^$C/EBP${\alpha}$/, p38$\^$C/EBP${\beta}$/, and p35$\^$C/EBP${\beta}$ form specific complexes with the IGF-I exon 1 oligonucleotide in liver nuclear extract and that p42$\^$C/EBP${\alpha}$/ and p38$\^$C/EBP${\beta}$/ form complexes in brain. These data suggest that the formation of FRE-C/EBP isoform complexes may play important roles in the tissue-specific regulation of IGF-I gene expression.

• Journal of Life Science
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• v.26 no.7
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• pp.758-763
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• 2016

Fatty acid transporters are key mediators of skeletal muscle lipid metabolism. Several protein groups have been implicated in cellular long-chain fatty acid uptake or oxidation, including fatty acid transporter proteins (FATPs), the plasma membrane fatty acid-binding protein (FABPpm), and the fatty acid translocase (FAT/CD36). FAT/CD36 is highly expressed in skeletal muscle and known to be regulated by various factors such as exercise and hormones. Insulin-like growth factor-I (IGF-I) is a well-known regulator of skeletal muscle cells. However, it has not been studied whether there is any interaction between IGF-I and FAT/CD36 in skeletal muscle cells. In this study, the effects of IGF-I treatment on FAT/CD36 induction were examined. Differentiated C2C12 cells were treated with 20 ng/ml of IGF-I at different time points. Treatment of C2C12 cells with IGF-I resulted in increased FAT/CD36 mRNA and protein expression. After 24 and 48 hr of IGF-I treatment, FAT/CD36 mRNA increased 89% and 24% respectively. The increase of both proteins returned to the control level after 72 hr of IGF-I treatment, suggesting that the FAT/CD36 gene is regulated pretranslationally by IGF-I in skeletal muscle cells. These results suggest that IGF-I can regulate the expression of FAT/CD36 in skeletal muscle cells. In conclusion, IGF-I induces a rapid transcriptional modification of the FAT/CD36 gene in C2C12 skeletal muscle cells and has modulating effects on fatty acid uptake proteins as well as oxidative proteins.

• Journal of Life Science
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• v.19 no.3
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• pp.305-310
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• 2009

Plasmid pGKV21 contains a 229-nucleotide (nt) single-strand DNA initiation (ssi) signal. Using asymmetric PCR, we prepared a small single-stranded (ss) DNA fragment of the ssi signal and, using the 229-nt ssDNA fragment, determined the requirements of RNA polymerase for priming and DNA-protein interaction. The ssi fragment prepared was able to generate primer RNAs with almost the same efficiency as the $M13{\Delta}lac182/229$ phage DNA. However, the cssi (complementary strand of the ssi signal) fragment could not synthesize primer RNAs. This result suggests that the 229-nt ssi signal functions in a strand specific manner. Gel retardation and DNase I footprinting demonstrated that the synthesized ssi fragment could interact with both E. coli RNA polymerase and SSB protein to synthesize primer RNA. In Escherichia coli [pWVAp], an addition of rifampicin resulted in an accumulation of ssDNA, indicating that the host-encoded RNA polymerase is involved in the conversion of ssDNA to double-stranded plasmid DNA.

• Biomolecules & Therapeutics
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• v.28 no.3
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• pp.272-281
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• 2020

Environmental agents, including viral and bacterial infectious agents, are involved in the alteration of physicochemical and biological parameters in the nasal epithelium. Hyaluronan (HA) has an important role in the regulation of tissue healing properties. High molecular weight HA (HMW-HA) shows greater anti-inflammatory responses than medium molecular weight HA (MMW-HA) and low molecular weight HA (LMW-HA). We investigated the effect of HMW-HA, MMW-HA and LMW-HA on the regulation of physicochemical and biological parameters in an "in vitro" model that might mimic viral infections of the nasal epithelium. Human nasal epithelial cell line RPMI2650 was stimulated with double-stranded RNA (dsRNA) Poly(I:C) for 5 days in air-liquid-interface (ALI) culture (3D model of airway tissue). dsRNA Poly(I:C) treatment significantly decreased transepithelial electrical resistance (TEER) in the stratified nasal epithelium of RPMI2650 and increased pH values, rheological parameters (elastic G' and viscous G''), and Muc5AC and Muc5B production in the apical wash of ALI culture of RPMI2650 in comparison to untreated cells. RPMI2650 treated with dsRNA Poly(I:C) in the presence of HMW-HA showed lower pH values, Muc5AC and Muc5B production, and rheological parameters, as well as increased TEER values in ALI culture, compared to cells treated with Poly(I:C) alone or pretreated with LMW-HA and MMW-HA. Our 3D "in vitro" model of epithelium suggests that HMW-HA might be a coadjuvant in the pharmacological treatment of viral infections, allowing for the control of some physicochemical and biological properties affecting the epithelial barrier of the nose during infection.

• The Korean Journal of Mycology
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• v.12 no.3
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• pp.111-116
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• 1984

Ribonucleic acid contents and mononucleotides distribution from the mycelium and fruit bodies of Ganoderma lucidum were studied. P.E.I. cellulose TLC and HPLC were applied in this study. The obtained results are as follows; The levels of ribonucleic acids from the young basidiocarp mycelium were higher than those of mature basidiocarp. Guanosine 5'-monophosphate and xanthosine 5'-monophosphate were found in both young basidiocarp mycelium and mature basidiocarp. The levels of guanosine 5'-monophosphate and xanthosine 5'-monophosphate from the young basidiocarp were higher than those of the mature basidiocarp. However, inosine 5'-mono­phosphate was not detected.

• Korean Journal of Food Science and Technology
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• v.36 no.6
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• pp.986-990
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• 2004

The immunomodulatory effect of Codonopsis lanceolata based on the production of cytokines and the activation of macrophage was studied. The mRNA expression of nitric oxide synthase (iNOS) was gradually induced after 24 hr treatment of Codonopsis lanceolata, and NO production was a maximum after 24 hr treatment with 1 mg/mL. RAW 264.7 cell on in vitro treatment with Codonopsis lanceolata induced mRNA of cytokines such as interleukin-1(IL-1)${\beta}$, interleukin-6(IL-6), tumor necrosis $factor(TNF)-{\alpha}\;and\;interferon(IFN)-{\gamma}$; $IL-1{\beta}$ and IL-6 mRNA were gradually induced up to 24 hr, $TNF-{\alpha}\;mRNA$ was regularly induced up to 24 hr, and $IFN-{\gamma}\;mRNA$ level was a maximum within 1 hr. These results suggest that Codonopsis lanceolata exerts as an effective immunomodulator and enhances antitumor activity of macrophages.

• The Journal of Korean Obstetrics and Gynecology
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• v.26 no.2
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• pp.17-32
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• 2013

Objectives: The purpose of this study was to investigate whether Lonicera japonica(LJ) could inhibit LPS-induced type I IFN production. Methods: To evaluate inhibitory effect of LJ on type I IFN, we examined type I IFN, IRF-1, 7 and IL-10 production on LPS-induced macrophages using real time RT-PCR. Next, we observed the interaction of type I IFN, IRF-1, 7 and IL-10 using IL-10 neutralizing antibody. Finally we examined the activation of STAT-1, 3 using western blot. Results: LJ inhibited Type I IFN expression of mRNA and increased IL-10 expression of mRNA. Also LJ inhibited the level of IRF-1, 7 mRNA and the nuclear translocation of IRF-3. Further more, LJ reduced the activation of STAT-1, 3 which are involved in continuous secretion of immune cytokines. Blockade of IL-10 action caused a significant reduction of type I IFN and IRF-1, 7 than LPS-induced LJ pretreatment. Conclusions: LJ inhibits LPS-induced production of type I IFN by IL-10. This study may provide a clinical basis for anti-inflammatory properties of LJ.

• Nutritional Sciences
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• v.3 no.2
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• pp.57-65
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• 2000

Partial enteral nutrition (PEN) supplemented with insulin-like growth factor-I (IGF-I) to neonatal piglets receiving parenteral nutrition increases lactase-phlorizin hydrolase (LPH) activity, but not LPH mRNA. The goal of the current study was to investigate the mechanism by which IGF-I up-regulates LPH activity. We hypothesized that IGF-I regulates LPH synthesis post-transcriptionally. Methods: Newborn piglets (n=15) received 100% parenteral nutrition (TPN), 80% parenteral nutrition + 20% PEN (PEN), or PEN + IGF-I (1.0mg/kg/d). On day 7, two stable isotopes of leucine, [$^2 H_3$]-leucine and [$^{13}C_1$]-L-leucine were intravenously administered to measure mucosal protein and brush LPH (BB LPH) synthesis. Results: Weight gain, nutrient intake and jejunal weight and length were similar among the treatment groups. PEN increased mucosal weight, villus width and cross-sectional area, LPH activity, mRNA expression and the abundance of proLPHh compared to 100% TPN (p<0.05). IGF-I further increased mucosal weight, LPH activity and LPH activity per unit BB LPH ~2-fold over PEN alone (p<0.05), but did not affect LPH mRNA or the abundance of proLPHh or mature LPH. Isotopic enrichment of [$^2 H_3$]-leucine and [$^{13}C_1$]-L-leucine in plasma, mucosal protein and LPH precursors, and the fractional and absolute synthesis rates of mucosal protein and LPH were similar among the treatment groups. Total mucosal protein synthesis was increased 60% (p<0.05) and LPH synthesis tended (p=0.14) to be greater in the IGF-I treated animals compared to the other two groups. Conclusions: The primary mechanism by which IGF-I up-regulates LPH may be post-translational, either via reducing LPH turnover, or by specifically altering LPH activity.