• Journal of the Korean Society of Food Science and Nutrition
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• 제26권4호
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• pp.697-703
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• 1997

This study was planned to compare the effects of source of dietary n-3 fatty acids, i.e., tuna oil and perilla oil, on mitogenesis and production of prostaglandin E$_2$ and leukotriene B$_4$ in rats. Weaning male Sprague-Dawley rats were fed 3 different experimental diets for 4 weeks(Control: beef tallow 50% + sesame oil 50%, FO : beef tallow 50% + sesame oil 25% + tuna oil(27% docosahexaenoic acid) 25%, PO : beef tallow 50% + sesame oil 25% + perilla oil 25%). Food intakes were higher in FO group than in other groups, but body weight gains, food efficiency rates and weights of spleen were not different among groups. Proliferation of splenocyte to PWM(pokeweedmitogen) was higher in FO and PO group than control group. But there was no difference between FO and PO group. Response to ConA was not different among three groups. Serum PGE$_2$ levels were higher in control group than other groups. Serum LKB$_4$ levels were not different among groups. Therefore, it seemed that n-3 fatty acids increased the immune response by means of decreasing the PGE$_2$ production.

• The korean journal of orthodontics
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• 제24권4호
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• pp.871-883
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• 1994

This experiment was designed to study possible roles of $interleukin-1\beta$, interleukin-6 and tumor necrosis $factor-\alpha$ in bone remodeling by measuring their effects on $PGE_2,\; LTB_4$ and collagenase production when they were administered to human periodontal ligament fibroblasts. Human periodontal ligament fibroblasts were collected from first premolars extracted for orthodontic treatment. They were incubated in the environment of $37^{\circ}C,\;5\%\;Co^2,\;and\;100\%$ humidity. They were treated with $0.25\%$ trypsin-EDTA solution and centrifuged. PDL cells in the fifth to seventh passage were used for the experiment. Cells were seeded onto the culture dishes and when they were successfully attached, human recombinant $interleukin-1\beta$, interleukin-6, and tumor necrosis $factor-\alpha$ were administered, alone or in combination. They were incubated for 4, 8 and 24 hours and the levels of $PGE_2,\;LTB_4$ and collagenase released into the culture media were assessed by enzymeimmunoassay and collagenase activity assay. The conclusions are as follows: 1. $IL-1\beta\;and\;TNF-\alpha$ were very active in stimulating the production of $PGE_2$ and collagenase by human periodontal ligament fibroblasts, while IL-6 increased $LTB_4$ production. 2. $IL-1\beta$ significantly increased $PGE_2$, but $LTB_4$ Production was not increased. $IL-1\beta$ is thought to act mainly via the cyclooxygenase pathway of arachidonic acid metabolism. 3. IL-6 tended to inhibit $IL-1\beta$ in the production of $PGE_2$ and collagense whereas IL-6 and $TNF-\alpha$ showed auditive effect in the level of $PGE_2$. The above cytokines increased the release of at least one of $PGE_2,\;LTB_4$ and collagenase. It suggests that cytokines are involved in bone remodeling process by stimulating PDL fibroblasts to produce various bone-resorptive agents. The roles of cytokines in bone remodeling as a whole would need further study.

• The Korean Journal of Physiology and Pharmacology
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• 제22권4호
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• pp.379-389
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• 2018

A nucleobase adenine is a fundamental component of nucleic acids and adenine nucleotides. Various biological roles of adenine have been discovered. It is not produced from degradation of adenine nucleotides in mammals but produced mainly during polyamine synthesis by dividing cells. Anti-inflammatory roles of adenine have been supported in IgE-mediated allergic reactions, immunological functions of lymphocytes and dextran sodium sulfate-induced colitis. However adenine effects on Toll-like receptor 4 (TLR4)-mediated inflammation by lipopolysaccharide (LPS), a cell wall component of Gram negative bacteria, is not examined. Here we investigated anti-inflammatory roles of adenine in LPS-stimulated immune cells, including a macrophage cell line RAW264.7 and bone marrow derived mast cells (BMMCs) and peritoneal cells in mice. In RAW264.7 cells stimulated with LPS, adenine inhibited production of pro-inflammatory cytokines $TNF-{\alpha}$ and IL-6 and inflammatory lipid mediators, prostaglandin $E_2$ and leukotriene $B_4$. Adenine impeded signaling pathways eliciting production of these inflammatory mediators. It suppressed $I{\kappa}B$ phosphorylation, nuclear translocation of nuclear factor ${\kappa}B$ ($NF-{\kappa}B$), phosphorylation of Akt and mitogen activated protein kinases (MAPKs) JNK and ERK. Although adenine raised cellular AMP which could activate AMP-dependent protein kinase (AMPK), the enzyme activity was not enhanced. In BMMCs, adenine inhibited the LPS-induced production of $TNF-{\alpha}$, IL-6 and IL-13 and also hindered phosphorylation of $NF-{\kappa}B$ and Akt. In peritoneal cavity, adenine suppressed the LPS-induced production of $TNF-{\alpha}$ and IL-6 by peritoneal cells in mice. These results show that adenine attenuates the LPS-induced inflammatory reactions.

• YAKHAK HOEJI
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• 제42권2호
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• pp.205-213
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• 1998

The efficacy of DA-6034, a new flavonoid derivative, was investigated in comparison with sulfasalazine in a trinitrobenzene sulfonic acid (TNBS)-induced rat colitis. Under light anaesthesia with ether, rats were subjected to intracolonic administration of 30mg TNBS in 50% ethanol (0.5ml) and were then sacrificed at 7 or 21 days after colitis induction. The TNBS control group (the saline treated colitic rat) exhibited ulceration and inflammation of the distal colon with formation of granuloma and pathologic connections. Moreover, an increase in colonic myeloperoxidase (MPO) activity (investigated as an index of leukocyte adhesion and accumulation) and an elevated colonic leukotriene $B_4$ ($LTB_4$) level were observed. The colitic rats received DA6034 (0.3-30mg/kg) or sulfasalazine (50-100mg/kg), prednisolone (0.3-3mg/kg) after the induction of colitis until they were sacrificed. Oral treatment with DA-6034 resulted in significant reductions of macroscopic colonic damage, colonic inflammation. DA6034 had a more potent effect than sulfasalazine and prednisolone on macroscopic colonic damage, while it has similar effect with prednisolone on the reduction of colonic $LTB_4$ synthesis and MPO activity. This study show, therefore, that DA-6034 is effective m attenuating the colonic lesion in an TNBS-induced colitis model. Furthermore, the results suggest that the effect of DA-6034 is partially related to its action on $LTB_4$ synthesis and MPO inhibition.

• Archives of Pharmacal Research
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• 제21권6호
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• pp.664-670
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• 1998

The role of intracellular $Ca^{2+}$, in the regulation of tumor cell proliferation by products of arachidonic acid (AA) metabolism was investigated using U-373 MG human as trocytoma cells. Treatment with nordihydroguaiaretic acid (NDGA), a lipoxygenase (LOX) inhibitor, or caffeic acid (CA), a specific 5-LOX inhibitor, suppressed proliferation of the tumor cells in a dose-dependent manner. However, indomethacin (indo), a cyclooxygenase (COX) inhibitor, did not significantly alter proliferation of the tumor cells. At anti-proliferative concentrations, NDGA and CA significantly inhibited intracellular $Ca^{2+}$ release induced by carbachol, a known intracelluar $Ca^{2+}$ agonist in the tumor cells. Exogenous administration of leukotriene $B_4(LTB_4)$, an AA metabolite of LOX pathway, enhanced proliferation of the tumor cells in a concentration-dependent fashion. In addition, $LTB_4$, induced intracelluar $Ca^{2+}$ release. Intracellular $Ca^{2+}$-inhibitors, such as an intracellular $Ca^{2+}$ chelator (BAPTA) and intracellular $Ca^{2+}$-release inhibitors (dantrolene and TMB-8), significantly blocked the LTB4-induced enhancement of cell proliferation and intracellular $Ca^{2+}$ release. These results suggest that LOX activity may be critical for cell proliferation of the human astrocytoma cells and that intracelluar $Ca^{2+}$ may play a major role in the mechanism of action of LOX.

• BMB Reports
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• 제49권4호
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• pp.232-237
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• 2016

Mulberry tree twigs (Ramulus mori) contain large amounts of oxyresveratrols and have traditionally been used as herbal medicines because of their anti-inflammatory properties. However, the signaling mechanism by which R. mori exerts its anti-inflammatory action remains to be elucidated. In this study, we observed that R. mori ethanol extracts (RME) exerted an inhibitory effect on the lipopolysaccharide (LPS)-induced production of the pro-inflammatory cytokine interleukin-6 (IL-6) in Raw264.7 macrophage cells. Additionally, RME inhibited IL-6 production by blocking the leukotriene B₄ receptor-2 (BLT2)-dependent-NADPH oxidase 1 (NOX1)-reactive oxygen species (ROS) cascade, leading to anti-inflammatory activity. Finally, RME suppressed the production of the BLT2 ligands LTB4 and 12(S)-HETE by inhibiting the p38 kinase-cytosolic phospholipase A₂-5-/12-lipoxygenase cascade in LPS-stimulated Raw264.7 cells. Overall, our results suggest that RME inhibits the 'BLT2 ligand-BLT2'-linked autocrine inflammatory axis, and that this BLT2-linked cascade is one of the targets of the anti-inflammatory action of R. mori.

• The Journal of Korean Medicine
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• 제33권4호
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• pp.26-36
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• 2012

Objectives: To establish scientific and objective evidence for the use of a Korean medicine, articles regarding Hwangryeonhaedok-tang (HRHDT), a herbal medicine frequently used in Korean medical clinics and hospitals, were gathered and analyzed. Methods: The articles were classified as being from domestic or international journals, and by their year of publication. The mechanisms of the anti-inflammatory and antipyretic effects of HRHDT were investigated. Results: Of the 25 articles analyzed, 7 were published from Korea, 7 were from China, and 11 were from Japan. HRHDT showed anti-inflammatory and antipyretic effects through the regulation of the expression of Th1 cytokines including interleukin-2 (IL-2), IL-8, interferon-${\gamma}$ (IFN-${\gamma}$), and tumor necrosis factor-${\alpha}$ (TNF-${\alpha}$); and Th2 cytokines including IL-4, IL-6, and IL-12, which inhibit leukotriene B4 (LTB4), cyclooxygenase-2 (COX-2), prostaglandin E2 (PGE2), and inflammatory cells. It also lowered preprodynorphin (PPD), and corticotropin-releasing factor (CRF) in the peripheral nerve system and hypothalamus. Conclusions: We speculate that the anti-inflammatory and antipyretic effects could be related to the therapeutic efficacy of HRHDT in removing pathogenic fire and heat.

• Journal of Microbiology and Biotechnology
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• 제31권9호
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• pp.1295-1304
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• 2021

Modified Renshen Wumei decoction (MRWD), a famous traditional Chinese medicine, is widely used for treating persistent diarrhea. However, as the mechanism by which MRWD regulates diarrhea remains unknown, we examined the protective effects of MRWD on intestinal barrier integrity in a diarrhea model. In total, 48 male rats were randomly distributed to four treatment groups: the blank group (CK group), model group (MC group), Medilac-Vita group (MV group) and Chinese herb group (MRWD group). After a 21-day experiment, serum and colon samples were assessed. The diarrhea index, pathological examination findings and change in ᴅ-lactate and diamine oxidase (DAO) contents illustrated that the induction of diarrhea caused intestinal injury, which was ameliorated by MV and MRWD infusion. Metabolomics analysis identified several metabolites in the serum. Some critical metabolites, such as phosphoric acid, taurine, cortisone, leukotriene B4 and calcitriol, were found to be significantly elevated by MRWD infusion. Importantly, these differences correlated with mineral absorption and metabolism and peroxisome proliferator-activated receptor (PPAR) pathways. Moreover, it significantly increased the expression levels of TLR4, MyD88 and p-NF-κB p65 proteins and the contents of IL-1 and TNF-α, while the expression levels of occludin, claudin-1 and ZO-1 proteins decreased. These deleterious effects were significantly alleviated by MV and MRWD infusion. Our findings indicate that MRWD infusion helps alleviate diarrhea, possibly by maintaining electrolyte homeostasis, improving the intestinal barrier integrity, and inhibiting the TLR4/NF-κB axis.

• Journal of the Society of Cosmetic Scientists of Korea
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• 제24권3호
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• pp.134-145
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• 1998

Facial hyperpigmentation in women, which is considered to be a serious cosmetic disability and a cause of mental distress, requires proper management. Melanocyte dendricity is a crucial factor affecting epidermal pigmentation. We found that BQ-788, the endothelin-B (ETB) receptor antagonist, blocks the formation of multi-dendricity which is induced by cocultured keratinocytes. Melanocytes in vivo show numerous dendrites which are in close contact with multiple keratinocytes, forming the epidermal-melanin unit. While melanocytes transfer their melanosomes into the neighboring keratinocytes via dendrites, keratinocytes secrete many growth factors and cytokines that influence viability, morphology, and melanin formation of melanocytes. Endothelin-1 (ET-1), prostaglandin E2(PGE2), and leukotriene-C4 (LT-C4) have been suggested as the candidates for increasing dendricity. Other reports suggested that ET-1 has stimulatory effects on proliferation and melanin formation of melanocytes in vitro. In the present study, using type-specific ET receptor antagonists, we observed how the morphology of melanocytes could be modulated in a coculture system. In addition, the roles of ET-1 for morphology and proliferation on melanocytes were evaluated in different culture media. We suggest that ET-1 increases dendricity and proliferation of melanocytes, and that its dendrite-inducing effect and mitogenic effect are regulated independently.

• Tuberculosis and Respiratory Diseases
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• 제45권2호
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• pp.369-379
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• 1998

Background: Platelet-activating factor(PAF) might play an important role in the development of acute respiratory distress syndrome. Since PAF induced lung injury is similar to changes of acute respiratory distress gyndrome, and abnormalities in surfactant function have been described in acute respiratory distress syndrome, the authors investigated the effects of PAF on the regulation of surfactant protein A, B and C mRNA accumulation Method: The effects of PAF on gene expression of surfactant protein A, B and C in 24 hours after intratracheal injection of PAF in rats. Surfactant protein A, B and C mRNAs were measured by filter hybridization. Results: The accumulation of SP-A mRNA in PAF treated group was significantly decreased by 37.1 % and 41.6%, respectively compared to the control group and the group treated with Lyso-PAF(p<0.025, p<0.01). The accumulation of SP-B mRNA in PAF treated group was decreased by 18.7% and 32.2 %, respectively compared to the control group and the group treated with Lyso-PAF but statistically not significant. The accumulation of SP-C mRNA in PAF treated group was significantly decreased by 30.7% and 38.5%, respectively compared to the control group and the group treated with Lyso-PAF(p<0.l, p<0.01). Conclusion: These findings represent a marked inhibitory effects of platelet-activating factor on surfactant proteins expression in vivo. This supports, in turn, 'platelet-activating factor might be related to pathogenesis of acute respiratory distress syndrome.