• Biomedical Science Letters
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• v.27 no.4
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• pp.223-230
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• 2021

Tumor necrosis factor alpha (TNF-α) is a principal regulator of inflammation and immunity. The proinflammatory properties of TNF-α can be attributed to its ability to activate the enzyme cytosolic phospholipase A₂ (cPLA₂), which generates potent inflammatory lipid mediators, eicosanoids. L-glutamine (Gln) plays physiologically important roles in various metabolic processes. We have reported that Gln has a potent anti-inflammatory activity via rapid upregulation of mitogen-activated protein kinases (MAPKs) phosphatase (MKP)-1, which preferentially dephosphorylates the key proinflammatory enzymes, p38 MAPK and cytosolic phospholipase A₂ (cPLA₂). In this study, we have investigated whether Gln could inhibit TNF-α-induced cPLA₂ activation. Gln inhibited TNF-α-induced increases in cPLA₂ phosphorylation in the lungs and blood levels of the cPLA₂ metabolites, leukotrine B4 (LTB4) (lipoxygenase metabolite) and prostaglandin E2 (PGE2) (cyclooxygenase metabolite). TNF-α increased p38 and cPLA₂ phosphorylation and blood levels of LTB4 and PGE2, which were blocked by the p38 inhibitor SB202190. Gln inhibited TNF-α-induced p38 and cPLA₂ phosphorylation and production of the cPLA₂ metabolites. Such inhibitory activity of Gln was no longer observed in MKP-1 small interfering RNA-pretreated animals. Our data indicate that Gln inhibited TNF-α-induced cPLA₂ phosphorylation through MKP-1 induction/p38 inhibition, and suggest that the utility of Gln in inflammatory diseases in which TNF-α plays a major role in their pathogenesis.

• Biomolecules & Therapeutics
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• v.24 no.2
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• pp.184-190
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• 2016

Rosa rugosa Thunb, a deciduous shrub of the genus Rosa, has been widely used to treat stomach aches, diarrhoea, pain, and chronic inflammatory disease in eastern Asia. In recent years, our research team has extensively studied the Rosa rugosa flower extract, and specifically undertook pharmacological experiments which have optimized the extraction process. Our methods have yielded a standard extract enriched in phenolic compounds, named PRE. Herein, we expand our efforts and evaluated the anti-inflammatory activity of PRE on lipopolysaccharide (LPS)-induced inflammation in RAW 264.7 macrophages. PRE significantly inhibited production of nitric oxide (NO), prostaglandin $E_2(PGE_2)$, tumor necrosis factor (TNF)-${\alpha}$, interleukin (IL)-6, and interleukin $1{\beta}$ (IL-$1{\beta}$), as well as expression of their synthesizing enzymes, inducible nitric oxide synthase (iNOS) and cyclooxygenase2 (COX-2). Furthermore, PRE inhibited activity of mitogen-activated protein kinases (MAPK) as well as nuclear factor-kappa B (NF-${\kappa}B$) signaling pathway. Our findings are the first to explain the anti-inflammatory mechanism by PRE in LPS-stimulated macrophages. Given these results, we propose that PRE has therapeutic potential in the prevention of inflammatory disorders.

• Nutrition Research and Practice
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• v.12 no.2
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• pp.101-109
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• 2018

BACKGROUD/OBJECTIVES: The objective of this study was to investigate the effects of vitamin C on inflammation, tumor development, and dysbiosis of intestinal microbiota in an azoxymethane (AOM)/dextran sulfate sodium (DSS)-induced inflammation-associated early colon cancer mouse model. MATERIALS/METHODS: Male BALB/c mice were injected intraperitoneally with AOM [10 mg/kg body weight (b.w)] and given two 7-d cycles of 2% DSS drinking water with a 14 d inter-cycle interval. Vitamin C (60 mg/kg b.w. and 120 mg/kg b.w.) was supplemented by gavage for 5 weeks starting 2 d after the AOM injection. RESULTS: The vitamin C treatment suppressed inflammatory morbidity, as reflected by disease activity index (DAI) in recovery phase and inhibited shortening of the colon, and reduced histological damage. In addition, vitamin C supplementation suppressed mRNA levels of pro-inflammatory mediators and cytokines, including cyclooxygenase-2, microsomal prostaglandin E synthase-2, tumor necrosis $factor-{\alpha}$, Interleukin $(IL)-1{\beta}$, and IL-6, and reduced expression of the proliferation marker, proliferating cell nuclear antigen, compared to observations of AOM/DSS animals. Although the microbial composition did not differ significantly between the groups, administration of vitamin C improved the level of inflammation-related Lactococcus and JQ084893 to control levels. CONCLUSION: Vitamin C treatment provided moderate suppression of inflammation, proliferation, and certain inflammation-related dysbiosis in a murine model of colitis associated-early colon cancer. These findings support that vitamin C supplementation can benefit colonic health. Long-term clinical studies with various doses of vitamin C are warranted.

• YAKHAK HOEJI
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• v.46 no.4
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• pp.258-264
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• 2002

Zinc plays an important role in immunobiological responses, while excessive zinc attenuates immune functions in a dose-dependent manner. Zinc excess has been reported to increase levels of plasma prostaglandin E$_2$ (PGE$_2$), which is known to inhibit production of Th (helper T) 1-associated cytokines and to induce inflammatory responses. Thus, this study was investigated the effects of indomethacin, a potent inhibitor of PGE$_2$ synthesis, on the proinflammatory cytokine and lymphokine production in ICR mice exposed to excessive zinc. Indomethacin at doses of 5 mg/kg was administered i.p. 30 minutes before zinc chloride (Zn) 30 mg/kg orally daily for 10 days. Excessive Zn remarkedly increased tumor necrosis factor (TNF)-$\alpha$ and interleukin (IL)-1$\beta$ levels in both serum and splenic supernatants compared with those in controls, while indomethacin significantly reduced the excessive Zn-induced levels of IL-1$\beta$. In serum, excessive Zn significantly decreased the levels of IL-2 and interferon (IFN)-${\gamma}$ compared with those in controls, whereas indomethacin significantly enhanced the excessive Zn-decreased levels of IFN-${\gamma}$ but did not affect the Zn-decreased levels of serum IL-2. In splenic supernatants, All of excessive Zn, indomethacin, and combination of Zn and indomethacin significantly enhanced IL-2 levels compared with those in controls, but indomethacin didn't affect the Zn-induced production of IL-2. These data, therefore, suggest that indomethacin significantly attenuated the in vivo and ex vivo IL-1$\beta$ production increased by excessive zinc and remarkedly enhanced the in vivo excessive zinc-suppressed production of IFN-${\gamma}$ but not IL-2.

• Biomolecules & Therapeutics
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• v.25 no.5
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• pp.519-527
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• 2017

Excessive activation of microglia causes the continuous production of neurotoxic mediators, which further causes neuron degeneration. Therefore, inhibition of microglial activation is a possible target for the treatment of neurodegenerative disorders. Balanophonin, a natural neolignoid from Firmiana simplex, has been reported to have anti-inflammatory and anti-cancer effects. In this study, we aimed to evaluate the anti-neuroinflammatory effects and mechanism of balanophonin in lipopolysaccharide (LPS)-stimulated BV2 microglia cells. BV2 microglia cells were stimulated with LPS in the presence or absence of balanophonin. The results indicated that balanophonin reduced not only the LPS-mediated TLR4 activation but also the production of inflammatory mediators, such as nitric oxide (NO), prostaglandin E2 (PGE2), $Interleukin-1{\beta}$ ($IL-1{\beta}$), and tumor necrosis $factor-{\alpha}$ ($TNF-{\alpha}$), in BV2 cells. Balanophonin also inhibited LPS-induced inducible nitric oxide synthase (iNOS), and cyclooxygenase-2 (COX2) protein expression and mitogen activated protein kinases (MAPKs), including extracellular signal-regulated kinase (ERK1/2), c-Jun N-terminal kinase (JNK), and p38 MAPK. Interestingly, it also inhibited neuronal cell death resulting from LPS-activated microglia by regulating cleaved caspase-3 and poly ADP ribose polymerase (PARP) cleavage in N2a cells. In conclusion, our data indicated that balanophonin may delay the progression of neuronal cell death by inhibiting microglial activation.

• Korean Journal of Pharmacognosy
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• v.45 no.1
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• pp.17-22
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• 2014

Grapes has long been used for food, and reported as containing polyphenol which has antioxidant and anti-cancer effects. Neuroinflammation is chronic inflammation at the brain, lead to neurodegenerative diseases. In this study, quercetin-3-O-glucuronide (QG) isolated from the leaf of Vitis labruscana has anti-neuroinflammatory effects. QG were investigated using MTT assay, western blot, nitric oxide (NO) assay, prostaglandin $E_2$ ($PGE_2$) assay, cytokine assay in lipopolysaccharide (LPS)-induced inflammation in BV2 cells. QG dose-dependently attenuated the expression of inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2), accordingly inhibited the production of NO and $PGE_2$. QG decreases the levels of proinflammatory cytokine such as tumor necrosis factor-${\alpha}$ (TNF-${\alpha}$), interlukin-$1{\beta}$ (IL-$1{\beta}$). Thereby, QG may offer therapeutic potential for treatment of neurodegenerative disease related to neuroinflammation.

• Journal of Periodontal and Implant Science
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• v.35 no.3
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• pp.675-685
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• 2005

Bone resorption involves sequential stages of osteoclast precursor migration and differentiation of osteoclast precursors into multinucleated osteoclasts. Stromal cell derived factor (SDF)-1 is a chemotactic factor for osteoclast precursor migration. Matrix metalloproteinase (MMP)-9 is involved in migration of osteoclast precursors and activation of $interleukin(IL)-1{\beta}$. Alveolar bone destruction is a characteristic feature of periodontal disease. Treponema lecithinolyticum is a oral spirochete isolated from the periodontal lesions. The effect of lipopolysaccharide(LPS) from T. lecithinolyticum on expression of SDF-1 and MMP-9 was examined in cocultures of bone marrow cells and osteblasts derived from mouse calvariae. T. lecithinolyticum LPS increased expression of MMP-9 in the coculture. Polymyxin B, an inhibitor of LPS, abolished the increase of MMP-9 mRNA expression by LPS. LPS did not increase the expression of SDF-1, $IL-1{\beta}$ and tumor necrosis $factor(TNF)-{\alpha}$ mRNA in cocultures. Prostaglandin $E_2(PGE_2)$ up-regulated the expression of MMP-9 and NS398, an inhibitor of $PGE_2$ synthesis, down-regulated the induction of MMP-9 expression by T. lecitbinolyticm LPS. These results suggest that T. lecitbinolyticm LPS increases MMP-9 expression in bone cells via $PGE_2$ and that the induction of MMP-9 expression by T. lecitbinolyticm LPS is involved in alveolar bone destruction of periodontitis patients by the increase of osteoclast precursor migration and the activation of bone resorption-inducing cytokine.

• Food Science and Preservation
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• v.25 no.1
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• pp.107-116
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• 2018

The aim of this study is to investigate the antioxidant and intracellular anti-inflammatory efficacy of blueberry leaf extracted with hot water (BLW), 70% ethanol (BLE), and 70% acetone (BLA) in RAW 264.7 macrophages. In order to evaluate the anti-inflammatory effect of blueberry leaf extracts, RAW 264.7 macrophages were stimulated with lipopolysaccharide (LPS) to induce the production of inflammation-related factors, which were measure by Western blotting and real-time PCR methods. i-NOS, COX-2 protein, and mRNA expression showed concentration-dependent decrease. The decreases in the mRNA expression levels of interleukin-$1{\beta}$ (IL-$1{\beta}$), interleukin-6 (IL-6), tumor necrosis factor-${\alpha}$ (TNF-${\alpha}$), and prostaglandin $E_2$ ($PGE_2$) were concentration-dependent. Further, the antioxidant effects of blueberry leaf on total polyphenol contents, electron donating ability and $ABTS^+$ radical scavenging activity were evaluated. The total polyphenol contents of BLW, BLE, and BLA were $217.04{\pm}2.98$, $156.72{\pm}3.90$, and $182.88{\pm}3.02mg\;TAE/g$, respectively, while the electron donating abilities at $1,000{\mu}g/mL$ of BLW, BLE, and BLA were 81.7, 79.6, and 79.3%, respectively. The $ABTS^+$ radical scavenging activity was fond to be concentration dependent. The nitric oxide (NO) production inhibition activities at $50{\mu}g/mL$ of BLW, BLE, and BLA were 35.1, 42.4 and 42.7%, respectively. In conclusion, the antioxidant and anti-inflammatory test results indicate that blueberry leaf extracts (BLW, BLE, and BLA) can be used as potential anti-inflammatory agents.

• Toxicological Research
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• v.34 no.1
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• pp.65-73
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• 2018

Pretreatment of low-dose lipopolysaccharide (LPS) induces a hyporesponsive state to subsequent secondary challenge with high-dose LPS in innate immune cells, whereas super-low-dose LPS results in augmented expression of pro-inflammatory cytokines. However, little is known about the difference between super-low-dose and low-dose LPS pretreatments on immune cell-mediated inflammatory and hepatic acute-phase responses to secondary LPS. In the present study, RAW 264.7 cells, EL4 cells, and Hepa-1c1c7 cells were pretreated with super-low-dose LPS (SL-LPS: 50 pg/mL) or low-dose LPS (L-LPS: 50 ng/mL) in fresh complete medium once a day for 2~3 days and then cultured in fresh complete medium for 24 hr or 48 hr in the presence or absence of LPS ($1{\sim}10{\mu}g/mL$) or concanavalin A (Con A). SL-LPS pretreatment strongly enhanced the LPS-induced production of tumor necrosis factor (TNF)-${\alpha}$, interleukin (IL)-6, TNF-${\alpha}$/IL-10, prostaglandin E2 ($PGE_2$), and nitric oxide (NO) by RAW 264.7 cells compared to the control, whereas L-LPS increased IL-6 and NO production only. SL-LPS strongly augmented the Con A-induced ratios of interferon (IFN)-${\gamma}$/IL-10 in EL4 cells but decreased the LPS-induced ratios of IFN-${\gamma}$/IL-10 compared to the control, while L-LPS decreased the Con A- and LPS-induced ratios of IFN-${\gamma}$/IL-10. SL-LPS enhanced the LPS-induced production of IL-6 by Hepa1c1c-7 cells compared to the control, while L-LPS increased IL-6 but decreased IL-$1{\beta}$ and C reactive protein (CRP) levels. SL-LPS pretreatment strongly enhanced the LPS-induced production of TNF-${\alpha}$, IL-6, IL-10, $PGE_2$, and NO in RAW 264.7 cells, and the IL-6, IL-$1{\beta}$, and CRP levels in Hepa1c1c-7 cells, as well as the ratios of IFN-${\gamma}$/IL-10 in LPS- and Con A-stimulated EL4 cells compared to L-LPS. These findings suggest that pre-conditioning of SL-LPS may contribute to the mortality to secondary infection in sepsis rather than pre-conditioning of L-LPS.

• Journal of dental hygiene science
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• v.19 no.1
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• pp.39-47
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• 2019

Background: Light-emitting diodes curing unit (LCU), which emit blue light, is used for polymerization of composite resins in many dentistry. Although the use of LCU for light-cured composite resin polymerization is considered safe, it is still controversial whether it can directly or indirectly have harmful biological influences on oral tissues. The aim of this study was to elucidate the biological effects of LCU in wavelengths ranging from 440 to 490 nm, on the cell viability and secretion of inflammatory cytokines in MDPC-23 odontoblastic cells and inflammatory-induced MDPC-23 cells by lipopolysaccharide (LPS). Methods: The MTT assay and observation using microscope were performed on MDPC-23 cells to investigate the cell viability and cytotoxic effects on LCU irradiation. Results: MDPC-23 cells and LPS stimulated MDPC-23 cells were found to have no effects on cell viability and cell morphology in the LCU irradiation. Nitric oxide (NO) and prostaglandin $E_2$ which are the pro-inflammatory mediators, and interleukin-$1{\beta}$ and tumor necrosis factor-${\alpha}$ (TNF-${\alpha}$) which are the proinflammatory cytokines were significantly increased in MCPD-23 cells after LCU irradiation as time increased in comparison with the control. LCU irradiation has the potential to induce inflammation or biological damages in normal dental tissues, including MDPC-23 cells. Conclusion: Therefore, it is necessary to limit the use of LCU except for the appropriate dose and irradiation time. In addition, LCU irradiation of inflammatory-induced MDPC-23 cells by LPS was reduced the secretion of NO compared to the LPS alone treatment group and was significantly reduced the secretion of TNF-${\alpha}$ in all the time groups. Therefore, LCU application in LPS stimulated MDPC-23 odontoblastic cells has a photodynamic therapy like effect as well as inflammation relief.