Protective effects of aminoethyl-chitooligosaccharides against oxidative stress in mouse macrophage RAW 264.7 cells

2012 ◽  
Vol 50 (3) ◽  
pp. 624-631 ◽  
Author(s):  
Dai-Nghiep Ngo ◽  
Moon-Moo Kim ◽  
Se-Kwon Kim
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.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Haidy A. Saleh ◽  
Eman Ramdan ◽  
Mohey M. Elmazar ◽  
Hassan M. E. Azzazy ◽  
Anwar Abdelnaser

AbstractDoxorubicin (DOX) chemotherapy is associated with the release of inflammatory cytokines from macrophages. This has been suggested to be, in part, due to DOX-mediated leakage of endotoxins from gut microflora, which activate Toll-like receptor 4 (TLR4) signaling in macrophages, causing severe inflammation. However, the direct function of DOX on macrophages is still unknown. In the present study, we tested the hypothesis that DOX alone is incapable of stimulating inflammatory response in macrophages. Then, we compared the anti-inflammatory effects of curcumin (CUR), resveratrol (RES) and sulforaphane (SFN) against lipopolysaccharide/interferon-gamma (LPS/IFN-γ)-mediated inflammation in the absence or presence of DOX. For this purpose, RAW 264.7 cells were stimulated with LPS/IFN-γ (10 ng/mL/10 U/mL) in the absence or presence of DOX (0.1 µM). Our results showed that DOX alone is incapable of stimulating an inflammatory response in RAW 264.7 macrophages. Furthermore, after 24 h of incubation with LPS/IFN-γ, a significant increase in tumor necrosis factor-alpha (TNF-α), interleukin-6 (IL-6), and inducible nitric oxide synthase (iNOS) mRNA levels was observed. Similarly, nitric oxide (NO) production and TNF-α and IL-6 protein levels were significantly upregulated. Moreover, in LPS/IFN-γ-treated macrophages, the microRNAs (miRNAs) miR-146a, miR-155, and miR-21 were significantly overexpressed. Interestingly, upon testing CUR, RES, and SFN against LPS/IFN-γ-mediated inflammation, only SFN was able to significantly reverse the LPS/IFN-γ-mediated induction of iNOS, TNF-α and IL-6 and attenuate miR-146a and miR-155 levels. In conclusion, SFN, at the transcriptional and posttranscriptional levels, exhibits potent immunomodulatory action against LPS/IFN-γ-stimulated macrophages, which may indicate SFN as a potential treatment for DOX-associated inflammation.


2021 ◽  
Vol 2021 ◽  
pp. 1-11
Author(s):  
Jinfang Deng ◽  
Zhenpeng He ◽  
Xiuru Li ◽  
Wei Chen ◽  
Ziwen Yu ◽  
...  

Background. Huangkui capsule (HKC) comprises the total flavonoid extract of flowers of Abelmoschus manihot (L.) Medicus. This study aimed to explore the effects of HKC on lipopolysaccharide- (LPS-) induced acute lung injury (ALI) in mice and LPS-stimulated RAW 264.7 cells. Methods. Enzyme-linked immunosorbent assay, histopathology, spectrophotometry, and quantitative real-time polymerase chain reaction were used for the assessments. Statistical analysis was performed using a one-way analysis of variance. Results. LPS significantly increased lung inflammation, neutrophil infiltration, and oxidative stress and downregulated lung miR-451 expression. Treatment with HKC dramatically attenuated the lung wet/dry weight ratio, reduced the total cell count in the bronchoalveolar lavage fluid (BALF), and inhibited myeloperoxidase activity in the lung tissues 24 h after LPS challenge. Histopathological analysis demonstrated that HKC attenuated LPS-induced tissue oedema and neutrophil infiltration in the lung tissues. Additionally, the concentrations of tumour necrosis factor- (TNF-) α and interleukin- (IL-) 6 in BALF and IL-6 in the plasma reduced after HKC administration. Moreover, HKC could enhance glutathione peroxidase and catalase activities and upregulate the expression of miR-451 in the lung tissues. In vitro experiments revealed that HKC inhibited the production of nitric oxide, TNF-α, and IL-6 in LPS-induced RAW 264.7 cells and mouse primary peritoneal macrophages. Additionally, HKC downregulated LPS-induced transcription of TNF-α and IL-6 in RAW 264.7 cells. Conclusions. These findings suggest that HKC has anti-inflammatory and antioxidative effects that may protect mice against LPS-induced ALI and macrophage activation.


2019 ◽  
Vol 49 (2) ◽  
pp. 93
Author(s):  
Yujin Jin ◽  
Naehwan Baek ◽  
Soyoung Back ◽  
Chang-Seon Myung ◽  
Kyung-Sun Heo

2020 ◽  
Vol 2020 ◽  
pp. 1-13
Author(s):  
Dong-Woo Lim ◽  
Hee-Jin Choi ◽  
Sun-Dong Park ◽  
Hyuck Kim ◽  
Ga-Ram Yu ◽  
...  

Despite its deleterious effects on living cells, oxidative stress plays essential roles in normal physiological processes and provides signaling molecules for cell growth, differentiation, and inflammation. Macrophages are equipped with antioxidant mechanisms to cope with intracellular ROS produced during immune response, and Nrf2 (NF-E2-related factor 2)/HO-1 (heme oxygenase-1) pathway is an attractive target due to its protective effect against ROS-induced cell damage in inflamed macrophages. We investigated the effects of ethanol extract of A. villosum (AVEE) on lipopolysaccharide- (LPS-) stimulated inflammatory responses generated via the Nrf2/HO-1 signaling pathway in murine peritoneal macrophages and RAW 264.7 cells. AVEE was found to suppress the NF-κB signaling pathway, thus, to reduce proinflammatory cytokine, nitric oxide, and prostaglandin levels in peritoneal macrophages and Raw 264.7 cells treated with LPS, and to enhance HO-1 expression by activating Nrf2 signaling. Furthermore, these anti-inflammatory effects of AVEE were diminished when cells were pretreated with SnPP (a HO-1 inhibitor). HPLC analysis revealed AVEE contained quercetin, a possible activator of the Nrf2/HO-1 pathway. These results show A. villosum ethanol extract exerts anti-inflammatory effects by activating the Nrf2/HO-1 pathway in LPS-stimulated macrophages.


2001 ◽  
Vol 69 (5) ◽  
pp. 3214-3223 ◽  
Author(s):  
Xiaohan Du ◽  
Martin G. Low

ABSTRACT Serum glycosylphosphatidylinositol-specific phospholipase D (GPI-PLD) activity is reduced over 75% in systemic inflammatory response syndrome. To investigate the mechanism of this response, expression of the GPI-PLD gene was studied in the mouse monocyte-macrophage cell line RAW 264.7 stimulated with lipopolysaccharide (LPS; 0.5 to 50 ng/ml). GPI-PLD mRNA was reduced approximately 60% in a time- and dose-dependent manner. Oxidative stress induced by 0.5 mM H2O2 or 50 μM menadione also caused a greater than 50% reduction in GPI-PLD mRNA. The antioxidant N-acetyl-l-cysteine attenuated the down-regulatory effect of H2O2but not of LPS. Cotreatment of the cells with actinomycin D inhibited down-regulation induced by either LPS or H2O2. The half-life of GPI-PLD mRNA was not affected by LPS, or decreased slightly with H2O2, indicating that the reduction in GPI-PLD mRNA is due primarily to transcriptional regulation. Stimulation with tumor necrosis factor alpha (TNF-α) resulted in ∼40% reduction in GPI-PLD mRNA in human A549 alveolar carcinoma cells but not RAW 264.7 cells, suggesting that alternative pathways could exist in different cell types for down-regulating GPI-PLD expression during an inflammatory response and the TNF-α autocrine signaling mechanism alone is not sufficient to recapitulate the LPS-induced reduction of GPI-PLD in macrophages. Sublines of RAW 264.7 cells with reduced GPI-PLD expression exhibited increased cell sensitivity to LPS stimulation and membrane-anchored CD14 expression on the cell surface. Our data suggest that down-regulation of GPI-PLD could play an important role in the control of proinflammatory responses.


Separations ◽  
2021 ◽  
Vol 8 (9) ◽  
pp. 129
Author(s):  
Uoorakkottil Ilyas ◽  
Deepshikha P. Katare ◽  
Punnoth Poonkuzhi Naseef ◽  
Mohamed Saheer Kuruniyan ◽  
Muhammed Elayadeth-Meethal ◽  
...  

Phyllanthus species (Family Euphorbiaceae) has been used in traditional medicine of several countries as a cure for numerous diseases, including jaundice and hepatitis. This study is an attempt to evaluate the immunomodulatory activity of various fractions, column eluents of ethyl acetate fraction, and their polyphenols. Phyllanthus maderaspatensis were standardized using high-performance liquid chromatography to identify and quantify polyphenols, and purification of polyphenols was carried out using vacuum liquid chromatography. Subsequently, we tested various fractions, column eluents of ethyl acetate fraction, and polyphenols in vitro to assess their impact on nitric oxide (NO) production in LPS-stimulated mouse macrophage RAW 264.7 cells. The ethyl acetate fraction (100 μg mL−1) had a more significant stimulatory effect on LPS-stimulated NO production by the RAW 264.7 cells. We found that the ethyl acetate fraction contains a high amount of catechin, quercetin, ellagic acid kaempferol, and rutin, which are responsible for immunomodulation. The ethyl acetate fraction at concentrations of 25 and 50 μg mL−1 had a significant inhibitory effect and 100 μg mL−1 had a more significant stimulatory effect when compared with the LPS control. The percentage of inhibition by LPS control ranged from zero percentage, kaempferol ranged from 45.4% at 50 μg mL−1 to 41.88% at 100 μg mL−1, catechin ranged from 50% at 50 μg mL−1 to 35.28% at 100 μg mL−1, rutin ranged from 36.2% at 50 μg mL−1 to 47.44% at 100 μg mL−1, gallic acid ranged from 28.4% at 50 μg mL−1 to 50.9% at 100 μg mL−1, ellagic acid ranged from 45.12% at 50 μg mL−1 to 38.64% at 100 μg mL−1, and purified quercetin ranged from 26.2% at 50 μg mL−1to 45.48% at 100 μg mL−1. As NO plays an important role in the immune function, polyphenols’ treatment could modulate several aspects of host defense mechanisms owing to the stimulation of the inducible nitric oxide synthase.


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