• Journal of Life Science
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• v.32 no.11
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• pp.899-907
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• 2022

Quercetin is one of bio-flavonoids which are abundant in fruits and vegetables and has been reported to have various pharmacological potentials such as anti-oxidation, anti-inflammation, anti-cancer, and anti-virus effects. In the present study, the anti-inflammatory effects and its working molecular mecha- nism of quercetin were investigated in mouse macrophage RAW264.7 cells. Quercetin significantly inhibited nitric oxide (NO) production in a dose-dependent manner without affecting cell viability and decreased inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) expression in LPS-stimulated RAW264.7 cells. In addition, quercetin decreased phosphorylation of p38, JNK, and ERK, and inhibited phosphorylation of NF-κB p65 protein and its inhibitor IκBα indicating that quercetin has the anti-inflammatory effects via regulation of MAPKs and NF-κB signaling pathway. We also detected expression changes of four kinds of pro-inflammatory cytokine genes (CSF2, IL-1β, IL-6, and TNF-α) with quantitative real-time PCR. The results showed that quercetin decreased the expression of four pro-inflammatory genes in LPS-stimulated RAW264.7 cells. Overall, our results showed that quercetin effectively suppressed inflammation responses induced by LPS in RAW264.7 cells via regulating MAPK and NF-κB pathway and down-regulating the expression of pro-inflammatory cytokine genes.

• Nutrition Research and Practice
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• v.17 no.1
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• pp.164-173
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• 2023

BACKGROUND/OBJECTIVES: Hyperglycemia is a major cause of diabetes and diabetesrelated diseases. Sodium butyrate (NaB) is a short-chain fatty acid derivative that produces dietary fiber by anaerobic bacterial fermentation in the large intestine and occurs in foods, such as Parmesan cheese and butter. Butyrate has been shown to prevent obesity, improve insulin sensitivity, and ameliorate dyslipidemia in diet-induced obese mice. Therefore, this study examined the effects and mechanism of NaB on the secretion of inflammatory cytokines induced by high glucose (HG) in THP-1 cells. MATERIALS/METHODS: THP-1 cells were used as an in vitro model for HG-induced inflammation. The cells were cultured under normal glycemic or hyperglycemic conditions with or without NaB (0-25 μM). Western blotting and quantitative polymerase chain reaction were used to evaluate the protein and mRNA levels of nuclear factor-κB (NF-κB), interleukin-6, tumor necrosis factor-α, acetylated p65, acetyl CREB-binding protein/p300 (CBP/p300), and p300 using THP-1 cells. Histone acetyltransferase (HAT), histone deacetylase (HDAC), and pro-inflammatory cytokine secretion activity were analyzed using an enzyme-linked immunosorbent assay. RESULTS: HG significantly upregulated histone acetylation, acetylation levels of p300, NF-κB activation, and inflammatory cytokine release in THP-1 cells. Conversely, the NaB treatment reduced cytokine release and NF-κB activation in HG-treated cells. It also significantly reduced p65 acetylation, CBP/p300 HAT activity, and CBP/p300 gene expression. In addition, NaB decreased the interaction of p300 in acetylated NF-κB and TNF-α. CONCLUSIONS: These results suggest that NaB suppresses HG-induced inflammatory cytokine production through HAT/HDAC regulation in monocytes. NaB has the potential for preventing and treating diabetes and its related complications.

• Journal of Microbiology and Biotechnology
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• v.30 no.4
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• pp.490-496
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• 2020

Consumption of anti-inflammatory nutraceuticals may help treat or prevent inflammation-related illnesses such as diabetes, cardiovascular disease, and cancer. This study evaluated the effect of Croton hirtus L'Hér extract (CHE) on lipopolysaccharide (LPS)-induced nitric oxide (NO) production and nuclear factor kappa-B (NF-κB) signaling cascades. CHE significantly suppressed LPS-induced NO production and inducible nitric oxide synthase (iNOS) expression in RAW264.7 macrophages, although cyclooxygenase (COX)-2 expression was not affected. CHE also suppressed LPS-induced IκB kinase (IKK), IκB, and p65 phosphorylation in RAW264.7 cells. Western blot and immunofluorescence assays of cytosol and nuclear p65 and the catalytic subunit of NF-κB showed that CHE suppressed LPS-induced p65 translocation from the cytosol to the nucleus. CHE also suppressed LPS-induced Interleukin (IL)-6 and tumor necrosis factor (TNF)-α production in RAW264.7 cells. These results suggest that CHE prevents NO-mediated inflammation by suppressing NF-κB and inflammatory cytokines.

• Journal of Physiology & Pathology in Korean Medicine
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• v.30 no.4
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• pp.242-249
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• 2016

This study was to investigate the anti-inflammatory effects of Prunellae Herba(PH). The generation of superoxide anion radical (․O₂-), nitric oxide (NO), peroxynitrite (ONOO-) and Prostaglandin E₂(PGE₂) were measured in the H₂O₂-Treated renal epithelial cells(LLC-PK1 cell) of mouse. And the effects of Prunellae Spica on the expression of NF-κB (p50, p65), IKK-α, phospho-IκB-α and inflammation-related proteins, COX-2, iNOS, IL-1β and VCAM-1, were examined by western blot. The fluorescent probes, 2',7'-dichlorodihydrofluorescein diacetate (DCFDA), 4,5-diaminofluorescein (DAF-2) and dihyldrorhodamine 123 (DHR 123) were used to estimate the scavenging effect of Prunellae Spica on ․O₂-, NO, ONOO-. Western blot was conducted to assess the protein expression levels of NF-κB (p50, p65), IKK-α, phospho-IκB-α, inflammation-related proteins, COX-2, iNOS, IL-1β, VCAM-1. PH inhibited H₂O₂-treated cell death dose-dependently. It reduced the generation of ·O₂-, NO, ONOO- and PGE₂ in the H₂O₂-treated renal epitheial cells(LLC-PK₁ cell) of mouse in vitro. PH reduced the expression of NF-κB, IKK-α, phospho-IκB-α, COX-2, iNOS, IL-1β and VCAM-1 genes through means of decreasing activation of NF-κB signaling as well. According to these results, PH has an antioxidative activity and anti-inflammatory effect by regulating the NF-κB pathway. This suggest that PH is expected to be used to regulating inflammatory process and treating inflammation-related disease.

• Herbal Formula Science
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• v.31 no.2
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• pp.99-109
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• 2023

Objectives : Sihosogan-tang (SST) is one of the traditional herbal formula and also one of the Korean medical insurance medicines. It commonly used in the treatment of hepatitis, chronic gastritis, intercostal neuralgia, pleurisy, and depression in East Asia. In the present study, we have demonstrated the anti-inflammatory effects of SST in macrophage cell line. Methods : To investigate mechanism of the anti-inflammatory effect of SST, we examined the productions of nitric oxide (NO) and pro-inflammatory cytokines, and the expressions of inducible NO synthase (iNOS), nuclear factor-κ B (NF-κB) and mitogen-activated protein kinase (MAPK) on RAW 264.7 cells activated by LPS. Results : SST significantly inhibited the expression of iNOS increased by LPS, and also significantly inhibited the production of NO. In addition, SST significantly inhibited pro-inflammatory cytokines such as TNF- α and interleukines. SST inhibited the expression of NF-κB and MAPK activation. Conclusions : These results suggest that SST ameliorates inflammatory response in LPS-activated RAW 264.7 cells through the inhibition of the NF-κB and MAPK pathway. Therefore, this study supplies objective evidence for the anti-inflammatory effect of SST.

• Journal of Life Science
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• v.33 no.6
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• pp.463-470
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• 2023

Desmarestia tabacoides Okamura is a brown macroalgae that is found worldwide. Although several genera of Desmarestia have been reported as having anti-tumorigenic, anti-melanogenic, and photoprotective properties, the anti-inflammatory activity of D. tabacoides Okamura has not yet been evaluated. In this study, we analyzed the anti-inflammatory mechanisms of D. tabacoides Okamura ethanol extract (DTEE) via the inhibition of nitric oxide (NO) and prostaglandin (PG) E₂ production and the expression of their corresponding enzymes, inducible NO synthase (iNOS), and cyclooxygenase (COX)-2. In addition, their upstream signaling molecules were evaluated by Western blot analysis, such as nuclear factor (NF)-κB, mitogen-activated protein kinase (MAPK), and phosphoinositide-3-kinase (PI3K)/Akt, in lipopolysaccharide (LPS)-stimulated RAW 264.7 cells. The DTEE treatment significantly inhibited LPS-induced NO and PGE₂ production as well as the expression of their corresponding enzymes, iNOS, and COX-2 without cytotoxicity. The stimulated transcription factor NF-κB and upstream signaling molecules extracellular signal-regulated kinase (ERK), c-Jun NH₂-terminal kinase (JNK), and p38 were attenuated by the DTEE treatment, which was statistically significant, while Akt did not provide any inhibitory effect. Moreover, the DTEE treatment significantly mitigated the LPS-activated adaptor molecules, toll-like receptor 4 (TLR4), and myeloid differentiation primary response 88 (MyD88) in the RAW 264.7 cells. These results suggest that DTEE attenuates TLR4-mediated inflammatory responses by inhibiting NF-κB activation and suppressing MAPK phosphorylation in LPS-stimulated RAW 264.7 cells.

• Nutrition Research and Practice
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• v.14 no.5
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• pp.453-462
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• 2020

BACKGROUND/OBJECTIVES: Platycodon grandiflorum (PG), an oriental herbal medicine, has been known to improve liver function, and has both anti-inflammatory and antimicrobial properties. However, little is known about the immune-enhancing effects of PG and its mechanism. In this study, we aimed to investigate whether fermented PG extract (FPGE), which has increased platycodin D content, activates the immune response in a murine macrophage cell line, RAW 264.7. MATERIALS/METHODS: Cell viability was determined by Cell Counting Kit-8 assay and the nitric oxide (NO) levels were measured using Griess reagent. Cytokine messenger RNA levels of were monitored by quantitative reverse transcription polymerase chain reaction. To investigate the molecular mechanisms underlying immunomodulatory actions of FPGE in RAW 264.7 cells, we have conducted luciferase reporter gene assay and western blotting. RESULTS: We found that FPGE treatment induced macrophage cell proliferation in a dose-dependent manner. FPGE also modulated the expression of NO and pro-inflammatory cytokines, such as tumor necrosis factor-α, interleukin (IL)-1β, and IL-6. The activation and phosphorylation levels of nuclear factor kappa B (NF-κB) were increased by FPGE treatment. Moreover, 5-aminoimidazole-4-carboxamide ribonucleotide, an activator of AMP-activated kinase (AMPK), significantly reduced both lipopolysaccharides- and FPGE-induced NF-κB reporter gene activity. CONCLUSIONS: Taken together, our findings suggest that FPGE may be a novel immune-enhancing agent acting via AMPK-NF-κB signaling pathway.

• Biomedical Science Letters
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• v.29 no.3
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• pp.137-143
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• 2023

Inflammation plays an important role in immune system's response to tissue injury and biological stimuli. However, excessive inflammation can cause tissue damage. Therefore, the development of naturally derived anti-inflammatory agents have received broad attention. In this study, we investigated the anti-inflammatory mechanism of Rubi Fructus (RF) extract on the mast cell-mediated inflammatory response. To determine the regulatory mechanism of RF in inflammatory reaction, we evaluated the effects of RF on secretion of interleukin (IL)-8, IL-6 and tumor necrosis factor (TNF)-α and activation of nuclear factor-κB (NF-κB) and caspase-1 in activated human mast cells-1 (HMC-1). The results showed that RF attenuated IL-8, IL-6 and TNF-α secretion in a concentration-dependent manner. Moreover, RF significantly attenuated caspase-1and NF-κB activation in activated HMC-1. Conclusively, the present results provide evidence that RF may be a promising agent for anti-inflammatory therapy.

• The Korea Journal of Herbology
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• v.34 no.6
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• pp.117-124
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• 2019

Objective : Broccoli is edible green plant that has a wide variety of health benefits including cancer prevention and cholesterol reduction. However, leaves of broccoli are not eaten and are mostly left as waste. This study was conducted to evaluate the effects of the broccoli leaf extract (BLE) on prostaglandin E₂ (PGE₂) production related to nuclear factor kappa B (NF-κB) signaling in lipopolysaccharide (LPS)-activated macrophages. Methods : BLE was prepared by extracting dried leaf with ethanol. Cell viability was determined by 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. PGE₂ and inflammatory cytokines were detected by enzyme-linked immunosorbent assay (ELISA). Expression level of each protein was monitored by Western blot analysis. Results : In LPS-activated Raw264.7 cells, PGE₂ release into culture medium was dramatically enhanced compared to control cells. However, increased PGE₂ was attenuated dose-dependently by treatment with BLE. Inhibition of PGE₂ production by BLE was due to the suppression of cyclooxygenase-2 (COX-2) expression determined by Western blot analysis. BLE also inhibited the production of inflammatory cytokines such as interleukin-6 (IL-6) and tumor necrosis factor-alpha (TNF-α). Inhibition at PGE₂ and cytokine was mediated from inhibition of nuclear translocation of NF-κB due to the repression of inhibitory kappa B alpha (IκBα) phosphorylation and degradation. Conclusion : This study showed that BLE exerted inhibitory activities against PGE₂, which is critical for the initiation and resolution of inflammatory responses, and that inhibition of PGE₂ was mediated by suppression of NF-κB signaling. These results suggest that the waste broccoli leaves could be used for controlling inflammation.

• Journal of Applied Biological Chemistry
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• v.66
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• pp.447-454
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• 2023

In the environment in which humans live, there are various antigens that invade the human body and interfere with humans leading a healthy life, so the immune system recognizes the antigen then removes them through a complex mechanism. Macrophages are widely distributed immune cells involved in the innate immune system, and produce various immune modulators such as inducible nitric oxide synthase-induced nitric oxide, cyclooxygenase-2 induced prostaglandin E2 and proinflammatory cytokines such as tumor necrosis factor-alpha. On the other hand, Protaetia brevitarsis seulensis larvae are a type of edible insect that have emerged as an alternative to the future food supply problem. The immuno-modulatory effect through the activation of murine macrophage RAW264.7 cell via mitogen-activated protein kinases (MAPKs)/nuclear factor-kappa B (NF-κB) signaling pathways has been reported. Based on this report, in this study, we confirmed how the expression of immune modulators induced by Protaetia brevitarsis seulensis larvae extracts in RAW264.7 cells was changed by treatment with pharmacological inhibitors of toll-like receptor 4 (TLR4), MAPKs and NF-κB signaling pathways. As a result, reduction of immune modulators was confirmed in the c-Jun N-terminal kinase (JNK) inhibitor treatment group and NF-κB inhibitor treatment group among the Protaetia brevitarsis seulensis larvae-treated RAW264.7 cell. Furthermore, in the TLR4 inhibitor-treated group, decreases in phosphorylation of JNK and NF-κB factors were confirmed in Protaetia brevitarsis seulensis larvae-treated RAW264.7 cell, as well as decreases in immune modulators. This results suggest that Protaetia brevitarsis seulensis larvae activates RAW264.7 cells by the engagement of TLR4-JNK/NF-κB signaling pathway.