• Biomolecules & Therapeutics
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• v.30 no.6
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• pp.570-575
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• 2022

Stress breaks body balance, which can cause diverse physiological disorders and worsen preexisting diseases. However, recent studies have reported that controllable stress and overcoming from stress reinforce resilience to resist against more intense stress afterwards. In this study, we investigated the protective effect of corticosterone (CORT), a representative stress hormone against hydrogen peroxide (H₂O₂)-induced neuronal cell death and its underlying molecular mechanism in SH-SY5Y cells, a human neuroblastoma cell line. The decreased cell viability by H₂O₂ was effectively restored by the pretreatment with low concentration of CORT (0.03 μM for 72 h) in the cells. H₂O₂-increased expression of apoptotic markers such as PUMA and Bim was decreased by CORT pretreatment. Furthermore, pretreatment of CORT attenuated H₂O₂-mediated oxidative damages by upregulation of antioxidant enzymes via activation of nuclear factor erythroid 2-related factor 2 (Nrf2). These findings suggest that low concentration of CORT with eustressed condition enhances intracellular self-defense against H₂O₂-mediated oxidative cell death, suggesting a role of low concentration of CORT as one of key molecules for resilience and neuronal cell survival.

• Journal of The Korean Society of Integrative Medicine
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• v.12 no.1
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• pp.1-10
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• 2024

Purpose: Lycopene is abundantly contained in Tomatoes and is known for diverse biological activities such as antioxidant, anti-inflammatory, and anticancer effects. In this study, the antioxidative potential of lycopene was investigated through the induction of hemeoxygenase (HO)-1 by nuclear factor-erythroid 2 p45-related factor2 (Nrf2) and upstream signaling molecules, mitogen-activated protein kinase (MAPK) and phosphoinositide 3-kinase (PI3K)/Aktin RAW 264.7 cells. Methods: The antioxidative potential of lycopene against oxidative stress and its molecular mechanisms were determined by the cell viability assay, intracellular reactive oxygen species (ROS) formation assay, and Western blot analysis in RAW 264.7 cells. Results: Lycopene treatment significantly attenuated tert-butyl hydroperoxide (t-BHP) induced intracellular ROS formation in a dose-dependent manner without any cytotoxicity. In addition, 50 µM of lycopene for 6 h treatment induced potent HO-1 expression and its transcription factor, Nrf2. MAPK and PI3K/Aktwere also analyzed due to their critical roles in the regulation of cellular redox homeostasis against oxidative damage. As a result, phosphorylation of extracellular regulated kinase (ERK) was significantly induced by lycopene treatment while the activated status of c-Jun NH2-terminal kinase (JNK), p38, and Akt, were not given any effect. To confirm the antioxidative mechanism of HO-1 mediated by ERK activation, each selective inhibitor was employed in a protection assay, in which oxidative damage occurred by t-BHP. Lycopene, SnPP, and CoPP treatments reflected accelerated HO-1 expression could be a protective role against oxidative damage-initiated cell death. A selective inhibitor for ERK significantly inhibited the lycopene-induced cytoprotective effect but selective inhibitors for other signaling molecules did not attenuate the rate of t-BHP-induced cell death. Conclusion: In conclusion, lycopene potently scavenged intracellular ROS formation and enhanced the HO-1 mediated antioxidative potential through the modulation of Nrf2, MAPK signaling pathway in RAW 264.7 cells.

• Journal of Life Science
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• v.28 no.2
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• pp.207-215
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• 2018

Inflammatory response and oxidative stress play critical roles in the development and progression of many human diseases. Therefore, a great deal of attention has been focused on finding functional materials that can control inflammation and oxidative stress simultaneously. The purpose of this study was to investigate the effects of Socheongja and Socheong 2, Korean black seed coat soybean varieties, on the inflammatory and oxidative stress induced by lipopolysaccharide (LPS) in RAW 264.7 macrophages. Our data indicated that the extracts of Socheongja (SCJ) and Socheong 2 (SC2) significantly suppressed LPS-induced production of nitrite oxide (NO) and prostaglandin $E_2$, key pro-inflammatory mediators, by suppressing the expression of inducible NO synthase and cyclooxygenase-2. It was also found that SCJ and SC2 reduced the LPS-induced secretion of pro-inflammatory cytokines, such as tumor necrosis $factor-{\alpha}$ and $interleukin-1{\beta}$, which was concomitant with a decrease in the protein levels. In addition, SCJ and SC2 markedly diminished LPS-stimulated intracellular reactive oxygen species accumulation, and effectively enhanced nuclear factor erythroid 2-related factor 2 (Nrf2) and heme oxygenase (HO)-1 expression. Furthermore, LPS-induced activation of mitogen-activated protein kinases (MAPKs) was abrogated by SCJ and SC2. Taken together, these data suggest that SCJ and SC2 may offer protective roles against LPS-induced inflammatory and oxidative responses in RAW 264.7 macrophages through attenuating MAPKs pathway, and these effects are mediated, at least in part, through activating Nrf2/HO-1 pathway. Given these results, we propose that SCJ and SC2 have therapeutic potential in the treatment of inflammatory and oxidative disorders caused by over-activation of macrophages.

• Tuberculosis and Respiratory Diseases
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• v.62 no.1
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• pp.33-42
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• 2007

Background: Heme oxygenase-1 (HO-1) is known to modulates the cellular functions, including cell proliferation and apoptosis. It is known that a high level of HO-1 expression is found in many tumors, and HO-1 plays an important role in rapid tumor growth on account of its antioxidant and antiapoptotic effects. Cisplatin is a widely used anti-cancer agent for the treatment of lung cancer. However, the development of resistance to cisplatin is a major obstacle to its use in clinical treatment. We previously demonstrated that inhibiting HO-1 expression through the transcriptional activation of Nrf2 induces apoptosis in A549 cells. The aim of this study was to determine of the inhibiting HO-1 enhance the chemosensitivity of A549 cells to cisplatin. Materials and Methods: The human lung cancer cell line, A549, was treated cisplatin, and the cell viability was measured by a MTT assay. The change in HO-1, Nrf2, and MAPK expression after the cisplatin treatment was examined by Western blotting. HO-1 inhibition was suppressed by ZnPP, which is a specific pharmacologic inhibitor of HO activity, and small interfering RNA (siRNA). Flow cytometry analysis and Western blot were performed in to determine the level of apoptosis. The level of hydrogen peroxide ($H_2O_2$) generation was monitored fluoimetrically using 2',7'-dichlorofluorescein diacetate. Results: The A549 cells showed more resistance to the cisplatin treatment than the other cell lines examined, whereas cisplatin increased the expression of HO-1 and Nrf2, as well as the phosphorylation of MAPK in a time-dependent fashion. Inhibitors of the MAPK pathway blocked the induction of HO-1 and Nrf2 by the cisplatin treatment in A549 cells. In addition, the cisplatin-treated A549 cells transfected with dither the HO-1 small interfering RNA (siRNA) or ZnPP, specific HO-1 inhibitor, showed in a more significantly decrease in viability than the cisplatin-only-treated group. The combination treatment of ZnPP and cisplatin caused in a marked increase in the ROS generation and a decrease in the HO-1 expression. Conclusion: Cisplatin increases the expression of HO-1, probably through the MAPK-Nrf2 pathway, and the inhibition of HO-1 enhances the chemosensitivity of A549 cells to cisplatin.

• Biomolecules & Therapeutics
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• v.20 no.6
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• pp.499-505
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• 2012

Chemoprevention represents a strategy designed to protect cells or tissues against various carcinogens and carcinogenic metabolites derived from exogenous or endogenous sources. Recent studies indicate that plant-derived triterpenoids, like oleanolic acid, may exert cytoprotective functions via regulation of the activity of different transcription factors. The chemopreventive effects may be mediated through induction of the nuclear factor erythroid 2-related factor 2 (Nrf2) transcription factor. Activation of Nrf2 by triterpenoids induces the expression of phase 2 detoxifying and antioxidant enzymes such as NAD(P)H quinone oxidoreductase 1 (NQO1) and heme oxygenase-1 (HO-1) - proteins which can protect cells or tissues against various toxic metabolites. On the other hand, inhibition of other transcription factors, like NF-${\kappa}B$ leads to the decrease in the pro-inflammatory gene expression. Moreover, the modulation of microRNAs activity may constitute a new mechanism responsible for valuable effects of triterpenoids. Recently, based on the structure of naturally occurring triterpenoids and with involvement of bioinformatics and computational chemistry, many synthetic analogs with improved biological properties have been obtained. Data from in vitro and in vivo experiments strongly suggest synthetic derivatives as promising candidates in the chemopreventive and chemotherapeutic strategies.

• Biomolecules & Therapeutics
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• v.27 no.1
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• pp.92-100
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• 2019

Ginger, one of worldwide consumed dietary spice, is not only famous as food supplements, but also believed to exert a variety of remarkable pharmacological activity as herbal remedies. In this study, a ginger constituent, 12-dehydrogingerdione (DHGD) was proven that has comparable anti-inflammatory activity with positive control 6-shogaol in inhibiting LPS-induced interleukin (IL)-6, tumor necrosis factor $(TNF)-{\alpha}$, prostaglandin (PG) $E_2$, nitric oxide (NO), inducible NO synthase (iNOS) and cyclooxygenase (COX)-2, without interfering with COX-1 in cultured microglial cells. Subsequent mechanistic studies indicate that 12-DHGD may inhibit neuro-inflammation through suppressing the LPS-activated $Akt/IKK/NF-{\kappa}B$ pathway. Furthermore, 12-DHGD markedly promoted the activation of NF-E2-related factor (Nrf)-2 and heme oxygenase (HO)-1, and we demonstrated that the involvement of HO-1 on the production of pro-inflammatory mediators such as NO and $TNF-{\alpha}$ by using a HO-1 inhibitor, Zinc protoporphyrin (Znpp). These results indicate that 12-DHGD may protect against neuro-inflammation by inhibiting $Akt/IKK/I{\kappa}B/NF-{\kappa}B$ pathway and promoting Nrf-2/HO-1 pathway.

• The Journal of Internal Korean Medicine
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• v.43 no.4
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• pp.643-655
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• 2022

Objective: To investigate the protective effects of Haeganjeon on a thioacetamide (TAA)-induced liver fibrosis mouse model and to determine the Haegan-jeon signaling pathway. Methods: Mice were randomly divided into 4 groups: Normal group (Nor), TAA-induced liver fibrosis group (Con), TAA-induced liver fibrosis group administered 50 mg/kg silymarin (S50), TAA-induced liver fibrosis group administered 200 mg/kg Haegan-jeon (H200). The liver fibrosis mouse model was established by intraperitoneal injection with TAA three times a week for 8 weeks. During the 8 weeks, mice were orally administered silymarin and Haegan-jeon every day. At the end of the study, serum was collected to measure the levels of AST, ALT, ammonia, and myeloperoxidase (MPO). Liver tissue was harvested and analyzed by western blotting and Masson's trichrome staining. Results: Administration of Haegan-jeon suppressed the increase in serum levels of AST, ALT, ammonia, and MPO due to TAA-induced liver fibrosis. Compared to the Con group, the H200 group showed increases in antioxidant-related factors (Nrf2, HO-1, catalase, and GPx-1/2) and decreases in inflammatory-related factors (NF-κB p65, p-IκB-α, Cox-2, iNOS, TNF-α, and IL-1β) in western blots. The H200 treatment inhibited the expression of α-SMA and Collagen I. Conclusions: Haegan-jeon showed a hepatoprotective effect induced by activation of antioxidant-related factors, such as Nrf2, and it regulated the inflammation response by suppression of NF-κB.

• 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 Ginseng Research
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• v.45 no.3
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• pp.408-419
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• 2021

Background: The decreased renal function is known to be associated with biological aging, of which the main pathological features are chronic inflammation and renal interstitial fibrosis. In previous studies, we reported that total saponins from Panax japonicus (SPJs) can availably protect acute myocardial ischemia. We proposed that SPJs might have similar protective effects for aging-associated renal interstitial fibrosis. Thus, in the present study, we evaluated the overall effect of SPJs on renal fibrosis. Methods: Sprague-Dawley (SD) aging rats were given SPJs by gavage beginning from 18 months old, at 10 mg/kg/d and 60 mg/kg/d, up to 24 months old. After the experiment, changes in morphology, function and fibrosis of their kidneys were detected. The levels of serum uric acid (UA), β2-microglobulin (β2-MG) and cystatin C (Cys C) were assayed with ELISA kits. The levels of extracellular matrix (ECM), matrix metalloproteinases (MMPs), tissue inhibitors of metalloproteinases (TIMPs), inflammatory factors and changes of oxidative stress parameters were examined. Results: After SPJs treatment, SD rats showed significantly histopathological changes in kidneys accompanied by decreased renal fibrosis and increased renal function; As compared with those in 3-month group, the levels of serum UA, Cys C and β2-MG in 24-month group were significantly increased (p < 0.05). Compared with those in the 24-month group, the levels of serum UA, Cys C and β2-MG in the SPJ-H group were significantly decreased. While ECM was reduced and the levels of MMP-2 and MMP-9 were increased, the levels of TIMP-1, TIMP-2 and transforming growth factor-β1 (TGF-β1)/Smad signaling were decreased; the expression level of phosphorylated nuclear factor kappa-B (NF-κB) was down-regulated with reduced inflammatory factors; meanwhile, the expression of nuclear factor erythroid 2-related factor 2-antioxidant response element (Nrf2-ARE) signaling was aggrandized. Conclusion: These results suggest that SPJs treatment can improve age-associated renal fibrosis by inhibiting TGF-β1/Smad, NFκB signaling pathways and activating Nrf2-ARE signaling pathways and that SPJs can be a potentially valuable anti-renal fibrosis drug.

• Journal of Nutrition and Health
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• v.56 no.5
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• pp.455-468
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• 2023

Purpose: Abeliophyllum distichum (A.distichum) is a plant native to Korea. In this study, we investigated the mechanism of antioxidant and anti-inflammatory effects of the leaf extract of A.distichum. Methods: The antioxidant capacity of the A.distichum leaf extract was determined based on the total polyphenol content, 2,2-diphenyl-1-picrylhydrazyl (DPPH) assay, 2,2'-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) assay, and the ferric reducing antioxidant power (FRAP) assay. The anti-inflammatory effects of the A.distichum leaf extract were evaluated by measuring the production of nitric oxide (NO) and the expression levels of proinflammatory cytokines including tumor necrosis factor (TNF)-α, interleukin (IL)-1β, and IL-6 using the enzyme-linked immunosorbent assay (ELISA) and reverse transcription quantitative real-time PCR (RT-qPCR). In addition, the expression of heme oxygenase-1 (HO-1), nuclear transcription factor-erythroid 2 related factor (Nrf2), inducible nitric oxide synthase (iNOS), and cyclooxygenase 2 (COX-2), as well as the activation of nuclear factorkappa B (NF-ĸB) were examined using the western blot analysis. Results: The total polyphenol content of the A.distichum leaf extract was 329.89 ± 30.17 gallic acid equivalents mg/g and the DPPH and ABTS scavenging activities were 55% and 70%, respectively. Additionally, the FRAP value of the extract was 743.68 ± 116.59 mg/mL. After 12-hour treatment with the A.distichum leaf extract, there was a tendency for the Nrf2 expression to increase, and the expression of HO-1 was significantly elevated in the RAW264.7 cells. The A.distichum leaf extract treatment resulted in decreased levels of NO, TNF-α, IL-6, and IL-1β, as well as reduced expression of iNOS and COX-2, along with inhibition of NF-κB activation in lipopolysaccharide-stimulated RAW264.7 cells. Conclusion: These results suggest that the A.distichum leaf extract exerts antioxidative and anti-inflammatory effects by upregulating the expression of HO-1 and downregulating NF-κB activation.