• Biomolecules & Therapeutics
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• v.29 no.6
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• pp.685-696
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• 2021

In this study, we investigated the inhibitory effect of 5-aminolevulinic acid (ALA), a heme precursor, on inflammatory and oxidative stress activated by lipopolysaccharide (LPS) in RAW 264.7 macrophages by estimating nitric oxide (NO), prostaglandin E2 (PGE2), cytokines, and reactive oxygen species (ROS). We also evaluated the molecular mechanisms through analysis of the expression of their regulatory genes, and further evaluated the anti-inflammatory and antioxidant efficacy of ALA against LPS in the zebrafish model. Our results indicated that ALA treatment significantly attenuated the LPS-induced release of pro-inflammatory mediators including NO and PGE2, which was associated with decreased inducible NO synthase and cyclooxygenase-2 expression. ALA also inhibited the LPS-induced expression of pro-inflammatory cytokines, such as tumor necrosis factor (TNF)-α, interleukin (IL)-1β, and IL-6, reducing their extracellular secretion. Additionally, ALA abolished ROS generation, improved the mitochondrial mass, and enhanced the expression of heme oxygenase-1 (HO-1) and the activation of nuclear translocation of nuclear factor-E2-related factor 2 (Nrf2) in LPS-stimulated RAW 264.7 macrophages. However, zinc protoporphyrin, a specific inhibitor of HO-1, reversed the ALA-mediated inhibition of pro-inflammatory cytokines production and activation of mitochondrial function in LPS-treated RAW 264.7 macrophages. Furthermore, ALA significantly abolished the expression of LPS-induced pro-inflammatory mediators and cytokines, and showed strong protective effects against NO and ROS production in zebrafish larvae. In conclusion, our findings suggest that ALA exerts LPS-induced anti-inflammatory and antioxidant effects by upregulating the Nrf2/HO-1 signaling pathway, and that ALA can be a potential functional agent to prevent inflammatory and oxidative damage.

• Journal of Life Science
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• v.29 no.4
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• pp.402-409
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• 2019

Korean red ginseng made from steaming and drying fresh ginseng has long been used as a traditional herbal medicine due to its effects on the immune, endocrine, and central nerve systems and its anti-inflammatory activity. In this study, we investigated the molecular mechanism responsible for the anti-inflammatory effects of a formulated Korean red ginseng extract (RGE) in response to lipoteichoic acid (LTA), a cell wall component of gram-positive bacteria. RGE inhibited LTA-induced nitric oxide (NO) secretion and inducible nitric oxide synthase (iNOS) expression in BV-2 microglial cells, without affecting cell viability. RGE also inhibited nuclear translocation of nuclear factor kappa B ($NF-{\kappa}B$) p65 and degradation of $I{\kappa}B-{\alpha}$. In addition, RGE increased the expression of heme oxygenase-1 (HO-1) in a dose-dependent manner, and the inhibitory effect of RGE on iNOS expression was abrogated by small interfering RNA-mediated knockdown of HO-1. Moreover, RGE induced nuclear translocation of nuclear factor E2-related factor 2 (Nrf2), a transcription factor that regulates HO-1 expression. Furthermore, the phosphoinositide-3-kinase (PI-3K) inhibitor and mitogen-activated protein kinase (MAPK) inhibitors suppressed RGE-mediated expression of HO-1, and RGE enhanced the phosphorylation of Akt, extracellular signal-regulated kinases (ERKs), p38, and c-JUN N-terminal kinases (JNKs). These results suggested that RGE suppressed the production of NO, a proinflammatory mediator, by inducing HO-1 expression via PI-3K/Akt- and MAPK-dependent signaling in LTA-stimulated microglia. The findings indicate that RGE could be used for the treatment of neuroinflammation induced by grampositive bacteria and that it may have therapeutic potential for various neuroinflammation-associated disorders.

• Food Science and Preservation
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• v.22 no.5
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• pp.735-743
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• 2015

This study investigated the anti-inflammatory activity of barley leaf extract in lipopolysaccharide (LPS)-stimulated RAW264.7 cells and hairless mice. Pre-treatment with barley leaf extract significantly inhibited the protein expression of inducible nitric oxide synthase (iNOS) and cyclooxygenase-II (COX-II) in a dose-dependent manner in LPS-stimulated RAW264.7 cells. Barley leaf extract also significantly inhibited the secretion of inflammatory cytokines, such as tumor necrosis factor-${\alpha}$ (TNF-${\alpha}$), interleukin-$1{\beta}$ (IL-$1{\beta}$), and interleukin-6 (IL-6). Moreover, phosphorylation of mitogen-activated protein kinases (MAPKs) and nuclear translocation of nuclear factor-kappa B (NF-${\kappa}B$) were strongly suppressed by barley leaf extract in LPS-stimulated cells. In hairless mice, barley extract significantly decreased the pathological phenotypes of contact dermatitis, such as erythema, edema, and scabs. These results indicate that barley leaf extract has an anti-inflammatory effect and therefore a possible role in the treatment of inflammatory diseases or in functional cosmetics.

• The Korean Journal of Physiology
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• v.24 no.2
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• pp.363-375
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• 1990

The present investigation was performed to purify bombesin-like immunoreactivity (BBS-LI) from the skin of frogs, B. orientalis inhabiting Korea. For extraction of BBS-LI, the fresh skin of 360 g from frogs was immersed in 1,800 ml of 100% methanol and then kept at $4^{\circ}C$ for 5 days. BBS-LI was partially purified by liquid chromatography using an alkaline alumina column followed by a Sephadex G-10 column. BBS-LI was further purified by using sequential HPLC of reversed phase C18 preparation, gel permeation, SP-ion exchange and reversed phase C18 analysis. BBS-LI in fractions of each step was monitored by radioimmunoassay for which bombesin antiserum with a titer of 1 : 188,800 was raised in a guinea pig. Eventually, two different BBS-LI were successfully purified and each BBS-LI showed the following character. 1) BBS-LI was well separated into two peaks in SP-ion exchange HPLC. One (BBS-LI-K1) bound to the column while the other (BBS-LI-K2) did not. 2) BBS-LI-K1, 73.8% of total BBS-LI, was not differentiated from synthetic bombesin in reversed phase C18 analytical and gel permeation HPLC. 3) BBS-LI-K2, 26.2% of total BBS-LI, eluted later than synthetic bombesin in reversed phase C18 analytical HPLC, but it eluted with a retention time identical to that of synthetic bombesin in gel permeation HPLC. 4) The two forms of BBS-LI and synthetic bombesin identically stimulated gastrin release and pancreatic exocrine secretion including volume, protein output and amylase output in anesthetized rats. It is concluded from the above results that the skin of B. orientalis contains two different forms of BBS-LI which are very identical to bombesin immunologically and biologically. In comparison with synthetic bombesin containing 14 amino acid residues, the major form shows quite similar pattern in all HPLC used in the present study, but the minor form exhibits quite different pattern in SP-ion exchange and reversed phase C18 analytical HPLG.

• Journal of Food Hygiene and Safety
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• v.22 no.3
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• pp.223-230
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• 2007

We have previously reported that green tea catechins(GTC) displayed potent antithrombotic effect, which was due to the antiplatelet activity. In the present study, the antiplatelet activity of each green tea catechin components was compared in vitro. Galloylated catechins including (-)-epigallocatechin gallate (EGCG), (-)-gallocatechin gallate (GCG), (-)-epicatechin gallate (ECG) and (-)-catechin gallate (CG), significantly inhibited collagen $(5{\mu}g/mL)-induced$ rabbit platelet aggregation with $IC_{50}$ values of 79.8, 63.0, 168.2 and $67.3{\mu}M$, respectively. EGCC GCG and CG also significantly inhibited arachidonic acid (AA, $100{\mu}M$)-induced rabbit platelet aggregation with $IC_{50}$ values of 98.9, 200.0 and $174.3{\mu}M$, respectively. However catechins without gallate moiety showed little inhibitory effects against rabbit platelet aggregation induced by collagen or AA compared with galloylated catechins. These observations suggest that the presence of gallate moiety at C-3 position may be essential to the antiplatelet activity of catechins and the presence of B ring galloyl structure may also contribute to the antiplatelet activity of GTC. In line with the inhibition of collagen-induced platelet aggregation, EGCG caused concentration-dependent decreases of cytosolic calcium mobilization, AA liberation and serotonin secretion. In contrast, epigallocatechin (EGC), a structural analogue of EGCG lacking a galloyl group in the 3' position, although slightly inhibited collagen-stimulated cytosolic calcium mobilization, failed to affect other signal transductions as EGCG in activated platelets. Taken together, these observations suggest that the antiplatelet activity of EGCG may be due to inhibition of arachidonic acid liberation and inhibition of $Ca^{2+}$ mobilization and that the antiplatelet of EGCG is enhanced by the presence of a gallate moiety esterified at carbon 3 on the C ring.

• Korean Journal of Poultry Science
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• v.34 no.2
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• pp.151-156
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• 2007

The Function of the calcium sensing receptor (CaSR) is to control calcium levels by altering PTH (parathyroid hormone) secretion and renal calcium resorption. The influence of calcium on the basal and stimulated release of several hormones from chicken pituitary glands has been determined in vitro. The objective of this study was to identify SNP in chicken CaSR gene and to investigate the effect of the SNP on economic traits. The sequencing analysis method was used to identify nucleotide polymorphisms within chicken CaSR gene. This study identified SNP at position 1949 bp(Genebank accession No : XM_416491) in the exon 1. The SNP changed the amino acid to alanine(GCC) from serine(TCC). This SNP showed three genotypes, AA, AS and SS by digestion with the restriction enzyme NcoⅠ using the PCR-RFLP method. The A963S showed significant effect only on the first lay day (P<0.05) in Leghorn population. Leghorn with the genotype AA had significantly faster the first lay day(137.6) than the genotype AS(143.0, P<0.05). Also, the A963S showed significant effect only on the first lay day(P<0.05) and mean of egg weight(P<0.05) in KNC population. KNC with the genotypes AA ans AS had significantly faster the first lay day (151.0 and 152.6, respectively) than the genotype SS(159.4, P<0.05). And the genotypes SS had significantly heavier the mean of egg weight(50.4 kg, P<0.05) than the genotype AA ans AS (47.5 and 47.8 kg, respectively). According to result of this study, an a allele of the A963S was found to have a significant effect on the first lay day. It will be possible to use this SNP marker on selecting chicken to improve the first lay day.