scholarly journals Fucoxanthin Inhibits Lipopolysaccharide-Induced Inflammation and Oxidative Stress by Activating Nuclear Factor E2-Related Factor 2 in Macrophages

2020 ◽  
Vol 4 (Supplement_2) ◽  
pp. 116-116
Author(s):  
Mi-Bo Kim ◽  
Hyunju Kang ◽  
Ji-Young Lee

Abstract Objectives Anti-inflammatory and antioxidant effects of fucoxanthin (FCX), a carotenoid present in edible brown seaweeds, have been suggested. However, the underlying mechanisms have not been fully understood. The objectives of this study were to determine whether FCX can inhibit lipopolysaccharide (LPS)-induced inflammation and oxidative stress and to elucidate the underlying mechanisms in macrophages. Methods Cytotoxicity of FCX (0–15 μM) was measured in RAW 264.7 macrophage. The effects of the FCX on LPS-induced inflammatory cytokine and antioxidant gene expression were determined in RAW 264.7 macrophages by quantitative realtime PCR, Western blot, and enzyme-linked immunosorbent assays. Cellular reactive oxygen species (ROS) accumulation was measured in LPS-induced RAW 264.7 macrophage. The antioxidant capacity was also determined by 2,2′-azinobis (3-ethylbenzothiazoline 6-sulfonate) (ABTS) radical scavenging activity expressed by trolox equivalent antioxidant capacity (TEAC). Also, a potential role of phosphatidylinositol 3-kinase (PI3K)/nuclear factor E2-related factor 2 (NRF2) axis, a crucial pathway in endogenous antioxidant defense, in the FCX effects was evaluated. Results Cells treated with 5 μM FCX were 90%<viable. LPS significantly increased mRNA levels of interleukin (Il)-6, Il-1β, and tumor necrosis factor α (Tnf) as well as TNFα secretion, which were significantly decreased by FCX. Elevated levels of cellular ROS levels by LPS were abolished by FCX with a concomitant increase in the expression of antioxidant enzymes. ABTS assay demonstrated that FCX had a stronger free radical scavenging property (57.6 TEAC μM/100 μM). Also, FCX significantly increased Nrf2 and heme oxygenase 1 expression compared to LPS control. LPS increased the nuclear translocation of NRF2, which was further increased by FCX. Interestingly, LY294002, an inhibitor of PI3K, noticeably decreased the effect of FCX on NRF2 nuclear translocation. Conclusions FCX exerts anti-inflammatory and antioxidant effects by the activation of NRF2 in LPS-induced macrophages. The increase in NRF2 nuclear translocation is mediated, at least in part, through the PI3K pathway. Funding Sources This study was supported by National Research Foundation of Korea (2019R1A6A3A03032678).

2021 ◽  
pp. 096032712110361
Author(s):  
Hai-Tao Zhang ◽  
Xi-Zeng Wang ◽  
Qing-Mei Zhang ◽  
Han Zhao

Objective To explore the mechanism of chromobox 7 (CBX7)-mediated nuclear factor E2-related factor 2 (Nrf2)/hemeoxygenase-1 (HO-1) signaling pathway in the cerebral ischemia/reperfusion (I/R) injury. Methods The experimental wild-type (WT) and CBX7-/- mice were used to establish cerebral I/R models using the middle cerebral artery occlusion (MCAO) surgery to determine CBX7 levels at different time points after MCAO injury. For all mice, neurological behavior, infarct size, water content, and oxidative stress–related indicators were determined, and transferase (TdT)-mediated dUTP-biotin nick-end labeling (terminal deoxynucleotidyl transferase (TdT)-mediated dUTP nick-end labeling (TUNEL)) staining method was employed to observe cell apoptosis, while Western blot to measure the expression of CBX7 and Nrf/HO-1 pathway-related proteins. Results At 6 h, 12 h, 24 h, 3 days, and 7 days after mice with MCAO, CBX7 expression was gradually up-regulated and the peak level was reached at 24 h. Mice in the WT + MCAO group had increased infarct size, with significant increases in the modified neurological severity scores and water content in the brain, as well as the quantity of TUNEL-positive cells. For the oxidative stress-indicators, an increase was seen in the content of MDA (malondial dehyde), but the activity of SOD (superoxide dismutase) and content of GSH-PX (glutathione peroxidase) and CAT (catalase) were decreased; meanwhile, the protein expression of CBX7, HO-1, and nuclear Nrf2 was up-regulated, while the cytoplasmic Nrf2 was down-regulated. Moreover, CBX7 knockout attenuated I/R injury in mice. Conclusion Knockout of CBX7 may protect mice from cerebral I/R injury by reducing cell apoptosis and oxidative stress, possibly via activating the Nrf2/HO-1 pathway.


2021 ◽  
Vol 11 (10) ◽  
pp. 4711
Author(s):  
Woo Jin Lee ◽  
Wan Yi Li ◽  
Sang Woo Lee ◽  
Sung Keun Jung

Until now, the physiological effects of Soroseris hirsuta were primarily unknown. Here we have evaluated the anti-inflammatory and antioxidant effects of Soroseris hirsuta extract (SHE) on lipopolysaccharide (LPS)-activated murine macrophages RAW 264.7 cells. SHE inhibited nitric oxide expression and inducible nitric oxide synthase expression in RAW 264.7 cells treated with LPS. Moreover, SHE suppressed LPS-induced phosphorylation of IκB kinase, inhibitor of kappa B, p65, p38, and c-JUN N-terminal kinase. Western blot and immunofluorescence analyses showed that SHE suppressed p65 nuclear translocation induced by LPS. Furthermore, SHE inhibited the reactive oxygen species in LPS-treated RAW 264.7 cells. SHE significantly increased heme oxygenase-1 expression and the nuclear translocation of nuclear factor erythroid 2-related factor 2. SHE suppressed LPS-induced interleukin-1β mRNA expression in RAW 264.7 cells. Thus, SHE is a promising nutraceutical as it displays anti-inflammatory and antioxidant properties.


2019 ◽  
Vol 2019 ◽  
pp. 1-18 ◽  
Author(s):  
Rong Wang ◽  
Yongzheng Luo ◽  
Yadong Lu ◽  
Daojuan Wang ◽  
Tingyu Wang ◽  
...  

Ulcerative colitis (UC) is a common chronic remitting disease driven through altered immune responses with production of inflammatory cytokines. Oxidant/antioxidant balance is also suggested to be an important factor for the recurrence and progression of UC. Maggots are known as a traditional Chinese medicine also known as “wu gu chong.” NF-E2-related factor-2 (Nrf2) transcription factor regulates the oxidative stress response and also represses inflammation. The aim of this study was to investigate the effects of maggot extracts on the amelioration of inflammation and oxidative stress in a mouse model of dextran sulfate sodium- (DSS-) induced colitis and evaluate if the maggot extracts could repress inflammation and oxidative stress using RAW 264.7 macrophages stimulated by lipopolysaccharide (LPS). In the present study, we found that the maggot extracts significantly prevented the loss of body weight and shortening of colon length in UC induced by DSS. Furthermore, DSS-induced expression of proinflammatory cytokines at both mRNA and protein levels in the colon was also attenuated by the maggot extracts. In addition, the maggot extracts could significantly suppress the expression of interleukin- (IL-) 1β, IL-6, TNF-α, NFκB p65, p-IκB, p22-phox, and gp91-phox in LPS-stimulated RAW 264.7 cells and colonic tissues. The maggot extracts increased the level of Nrf2 and prevented the degradation of Nrf2 through downregulating the expression of Keap1, which resulted in augmented levels of HO-1, SOD, and GSH-Px and reduced levels of MPO and MDA. However, after administering an Nrf2 inhibitor (ML385) to block the Nrf2/HO-1 pathway, we failed to observe the protective effects of the maggot extracts in mice with colitis and RAW 264.7 cells. Taken together, our data for the first time confirmed that the maggot extracts ameliorated inflammation and oxidative stress in experimental colitis via modulation of the Nrf2/HO-1 pathway. This study sheds light on the possible development of an effective therapeutic strategy for inflammatory bowel diseases.


Nutrients ◽  
2020 ◽  
Vol 12 (4) ◽  
pp. 1089 ◽  
Author(s):  
Sang Gil Lee ◽  
Cindi R. Brownmiller ◽  
Sun-Ok Lee ◽  
Hye Won Kang

Red clover (Trifolium pratense) possesses various dietary compounds that improve human health. However, the functions of anthocyanins in red clover remain unclear. Here we examined anti-inflammatory and antioxidant effects of red clover extract (RC) and red clover anthocyanins fraction (RCA) using lipopolysaccharide (LPS)-treated RAW 264.7 macrophages and identified dietary compounds. RC and RCA suppressed LPS-induced expression of genes such as tumor necrosis factor (TNF)α, interleukin (IL)1β, inducible nitric oxide synthase (iNOS), monocyte chemoattractant protein (MCP)1, and cyclooxygenase (COX)2. LPS-stimulated intracellular reactive oxygen species (ROS) production also was prevented by both RC and RCA. NADPH oxidase 1 (NOX1) gene and phosphorylation of p47phox of NOX1 that were increased by LPS were inhibited in the cells treated with RCA. LPS-stimulated nuclear factor erythroid 2-related factor 2 (NRF2) gene expression and nuclear translocation of nuclear factor kappa B (NF-kB) subunit p65 were suppressed together with reduced iNOS and COX2 proteins by RCA. Additionally, 27 polyphenols and 7 anthocyanins from RC were identified and quantified. In conclusion, RC, especially RCA, exerted anti-inflammatory and anti-oxidative activities in vitro by regulating NF-κB and NRF2 signaling pathways, suggesting that anthocyanins in red clover are the potential candidates to reduce inflammation and oxidative stress.


Antioxidants ◽  
2021 ◽  
Vol 10 (8) ◽  
pp. 1314
Author(s):  
Seung-Cheol Lee ◽  
Seung-Cheol Jee ◽  
Min Kim ◽  
Soee Kim ◽  
Min Kyoung Shin ◽  
...  

Benzo[a]pyrene (B[a]P) is a potentially hepatotoxic group-1 carcinogen taken up by the body through ingestion of daily foods. B[a]P is widely known to cause DNA and protein damages, which are closely related to cell transformation. Accordingly, studies on natural bioactive compounds that attenuate such chemical-induced toxicities have significant impacts on public health. This study aimed to uncover the mechanism of curcumin, the major curcuminoid in turmeric (Curcuma longa), in modulating the lipid accumulation and oxidative stress mediated by B[a]P cytotoxicity in HepG2 cells. Curcumin treatment reduced the B[a]P-induced lipid accumulation and reactive oxygen spicies (ROS) upregulation and recovered the cell viability. Cytochrome P450 family 1 subfamily A polypeptide 1 (CYP1A1) and Cytochrome P450 subfamily B polypeptide 1 (CYP1B1) downregulation resulting from decreased aryl hydrocarbon receptor (AhR) translocation into nuclei attenuated the effects of B[a]P-induced lipid accumulation and repressed cell viability, respectively. Moreover, the curcumin-induced reduction in ROS generation decreased the nuclear translocation of Nuclear factor erythroid-2-related factor 2 (Nrf2) and the expression of phase-II detoxifying enzymes. These results indicate that curcumin suppresses B[a]P-induced lipid accumulation and ROS generation which can potentially induce nonalcoholic fatty liver disease (NAFLD) and can shed a light on the detoxifying effect of curcumin.


2021 ◽  
Vol 15 ◽  
Author(s):  
Yue Fu ◽  
Jianping Jia

BackgroundNeuroinflammation and oxidative stress are two major pathological characteristics of Alzheimer’s disease (AD). Amyloid-β oligomers (AβO), a toxic form of Aβ, promote the neuroinflammation and oxidative stress in the development of AD. Isoliquiritigenin (ISL), a natural flavonoid isolated from the root of liquorice, has been shown to exert inhibitory effects on inflammatory response and oxidative stress.ObjectivesThe main purpose of this study is to assess the influence of ISL on inflammatory response and oxidative stress in BV2 cells stimulated with AβO, and to explore the underlying molecular mechanisms.Methods3-(4,5-dimethyl-2-thiazolyl)-2, 5-diphenyl-2-H- tetrazolium bromide (MTT) and lactate dehydrogenase (LDH) cytotoxicity assays were used to assess the toxic or protective effects of ISL. The expression levels of interleukin-1β, interleukin-6, and tumor necrosis factor-α were assessed by quantitative real-time polymerase chain reaction (qRT-PCR) and enzyme-linked immunosorbent assays. Morphological changes in BV2 cells were assessed by immunofluorescence method. Nitric oxide (NO) assay kit was used to determinate the NO production. Western blot, qRT-PCR and immunofluorescence were used to explore the underlying molecular mechanisms.ResultsISL treatment reduced the production of inflammatory cytokines and NO, and alleviated the morphological changes in BV2 cells induced by AβO. ISL treatment further protected N2a cells from the toxic medium of AβO-stimulated BV2 cells. ISL activated nuclear factor erythroid-2 related factor 2 (Nrf2) signaling and suppressed nuclear factor-κB (NF-κB) signaling in BV2 cells.ConclusionISL suppresses AβO-induced inflammation and oxidative stress in BV2 cells via the regulation of Nrf2/NF-κB signaling. Therefore, ISL indirectly protects neurons from the damage of toxic conditioned media.


Antioxidants ◽  
2020 ◽  
Vol 9 (3) ◽  
pp. 198 ◽  
Author(s):  
Ba-Wool Lee ◽  
Ji-Hye Ha ◽  
Han-Gyo Shin ◽  
Seong-Hun Jeong ◽  
Da-Bin Jeon ◽  
...  

Spiraea prunifolia var. simpliciflora (SP) is traditionally used as an herbal remedy to treat fever, malaria, and emesis. This study aimed to evaluate the anti-oxidative and anti-inflammatory properties of the methanol extract of SP leaves in tumor necrosis factor (TNF)-α-stimulated NCI-H292 cells and in a lipopolysaccharide (LPS)-induced acute lung injury (ALI) mouse model. SP decreased the number of inflammatory cells and the levels of TNF-α, interleukin (IL)-1β, and IL-6 in the bronchoalveolar lavage fluid, and inflammatory cell infiltration in the lung tissues of SP-treated mice. In addition, SP significantly suppressed the mRNA and protein levels of TNF-α, IL-1β, and IL-6 in TNF-α-stimulated NCI-H292 cells. SP significantly suppressed the phosphorylation of the mitogen-activated protein kinases (MAPKs) and p65-nuclear factor-kappa B (NF-κB) in LPS-induced ALI mice and TNF-α-stimulated NCI-H292 cells. SP treatment enhanced the nuclear translocation of nuclear factor erythroid 2-related factor (Nrf2) with upregulated antioxidant enzymes and suppressed reactive oxygen species (ROS)-mediated oxidative stress in the lung tissues of LPS-induced ALI model and TNF-α-stimulated NCI-H292 cells. Collectively, SP effectively inhibited airway inflammation and ROS-mediated oxidative stress, which was closely related to its ability to induce activation of Nrf2 and inhibit the phosphorylation of MAPKs and NF-κB. These findings suggest that SP has therapeutic potential for the treatment of ALI.


2020 ◽  
Vol 9 (4) ◽  
pp. 996
Author(s):  
Chih-Hsuan Hsia ◽  
Thanasekaran Jayakumar ◽  
Joen-Rong Sheu ◽  
Chih-Wei Hsia ◽  
Wei-Chieh Huang ◽  
...  

Activated microglia are crucial in the regulation of neuronal homeostasis and neuroinflammation. They also contribute to neuropathological processes after ischemic stroke. Thus, finding new approaches for reducing neuroinflammation has gained considerable attention. The metal ruthenium has gained notable attention because of its ability to form new complexes that can be used in disease treatment. [Ru(η6-cymene)2-(1H-benzoimidazol-2-yl)-quinoline Cl]BF4 (TQ-6), a potent ruthenium (II)-derived compound, was used in this study to investigate its neuroprotective action against microglia activation, middle cerebral artery occlusion (MCAO)-induced embolic stroke, and platelet activation, respectively. TQ-6 (2 μM) potently diminished inflammatory mediators (nitric oxide/inducible nitric oxide synthase (iNOS) and cyclooxygenase 2 (COX-2)) expression, nuclear factor kappa B (NF-κB) p65 phosphorylation, nuclear translocation, and hydroxyl radical (OH•) formation in LPS-stimulated microglia. Conversely, TQ-6 increased the expression of nuclear factor erythroid 2-related factor 2 (Nrf2) and heme oxygenase-1 (HO-1). Moreover, it significantly reduced brain infarct volume and edema in MCAO mice. Additionally, it drastically inhibited platelet aggregation and OH• production in mice platelets. This study confirmed that TQ-6 exerts an anti-neuroinflammatory effect on microglia activation through neuroprotection, antiplatelet activation, and free radical scavenging. The authors propose that TQ-6 might mitigate neurodegenerative pathology by inhibiting the NF-κB-mediated downstream pathway (iNOS and COX-2) and enhancing Nrf2/HO-1 signaling molecules in microglia.


2016 ◽  
Vol 130 (15) ◽  
pp. 1375-1387 ◽  
Author(s):  
Devy Deliyanti ◽  
Jae Young Lee ◽  
Steven Petratos ◽  
Colin J. Meyer ◽  
Keith W. Ward ◽  
...  

A novel and potent nuclear factor erythroid-2 related factor 2 (Nrf2) activator, dh404, attenuates retinal vasculopathy by reducing oxidative stress-mediated damage to glia. Nrf2 agonists represent an effective strategy to improve vision-threatening glial and vascular cell pathology in ischaemic retinopathies.


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