scholarly journals A pro-resolving phenotype underpins the anti-inflammatory effects of inorganic nitrate

2021 ◽  
Vol 42 (Supplement_1) ◽  
Author(s):  
C Primus ◽  
M Masucci ◽  
C Whitear ◽  
S A Montalvo Moreira ◽  
N Ajit Kumar ◽  
...  

Abstract Introduction Increasing evidence highlights the critical role of chronic inflammation in cardiovascular disease (CVD). Targeting inflammatory pathways in patients with CVD has been associated with improved CV function in pre-clinical (Gee, 2017), early clinical (Yndestad, 2006; Velmurugan 2013; Jones, 2016) and large phase III studies (Ridker, 2017). The resolution of inflammation is an active process and its failure has also been proposed to contribute to CVD progression. At least one mechanism thought to underlie this failure is dysfunction of the canonical pathway for anti-inflammatory nitric oxide (NO) production. Restoring NO through provision of inorganic nitrate (NO3-) and subsequent bioactivation via the non-canonical pathway may offer therapeutic benefit. Aim To test whether dietary NO3–derived NO accelerates resolution of inflammation. Methods Randomised, double-blind, placebo-controlled, parallel limb study of 8–10mmol dietary NO3- supplementation versus NO3–deplete placebo beetroot juice in 36 healthy male volunteers (NCT03183830). Using a cantharadin-induced skin blister model (Day, 2001), acute (24h) and chronic (72h)-phase blisters were harvested pre- and post-treatment. Blister exudate was analysed for leucocyte activation state (CD11b, CD62L, CD162) by flow cytometry and cytokine/chemokine composition by ELISA. Ozone chemiluminescence established NO3-/NO2- levels in key biological matrices: plasma, urine and saliva. Results 9.3mmol inorganic NO3- led to a significant rise (versus placebo, p<0.001) of NO3-/NO2- in plasma, saliva and urine NO2- (p<0.02). No differences were seen in blister volumes, cell counts or markers of systemic inflammation. Whilst no differences were seen in the proportions of cellular infiltrate in 24h blisters, there were significant reductions of neutrophil (p=0.017) and intermediate monocyte proportions (p=0.001) and cellular adhesion molecules across inflammatory, intermediate and resolving monocytes at 72h (Figure 1). Generally, no differences in blister cytokine/chemokine profile was evident except for borderline significant suppression of TNFα at 24hrs with dietary NO3- treatment (P=0.057). Conclusion Whilst dietary inorganic NO3- does not impair the essential host defence response it does accelerate resolution: enhanced pro- to anti-inflammatory monocyte subtype switching and curtailed neutrophil recruitment, likely via attenuated TNFα production. These actions offer a novel, easy to administer, approach to influence inflammatory responses without impairing host defence. FUNDunding Acknowledgement Type of funding sources: Public Institution(s). Main funding source(s): Derek Willoughby Trust and British Heart Foundation

Planta Medica ◽  
2010 ◽  
Vol 76 (12) ◽  
Author(s):  
V Francisco ◽  
A Figueirinha ◽  
B Neves ◽  
C Garcia-Rodriguez ◽  
M Lopes ◽  
...  

Author(s):  
Mona Aslani ◽  
Arman Ahmadzadeh ◽  
Zahra Aghazadeh ◽  
Majid Zaki-Dizaji ◽  
Laleh Sharifi ◽  
...  

Background: : Based on the encouraging results of phase III clinical trial of β-D-mannuronic acid (M2000) (as a new anti-inflammatory drug) in patients with RA, in this study, we aimed to evaluate the effects of this drug on the expression of chemokines and their receptors in PBMCs of RA patients. Methods:: PBMCs of RA patients and healthy controls were separated and the patients' cells were treated with low, moderate and high doses (5, 25 and 50 μg/mL) of M2000 and optimum dose (1 μg/mL) of diclofenac, as a control in RPMI-1640 medium. Real-time PCR was used for evaluating the mRNA expression of CXCR3, CXCR4, CCR2, CCR5 and CCL2/MCP-1. Cell surface expression of CCR2 was investigated using flow cytometry. Results:: CCR5 mRNA expression reduced significantly, after treatment of the patients' cells with all three doses of M2000 and optimum dose of diclofenac. CXCR3 mRNA expression down-regulated significantly followed by treatment of these cells with moderate and high doses of M2000 and optimum dose of diclofenac. CXCR4 mRNA expression declined significantly after treatment of these cells with moderate and high doses of M2000. CCL2 mRNA expression significantly reduced only followed by treatment of these cells with high dose of M2000, whereas, mRNA and cell surface expressions of CCR2 diminished significantly followed by treatment of these cells with high dose of M2000 and optimum dose of diclofenac. Conclusion:: According to our results, M2000 through the down-regulation of chemokines and their receptors may restrict the infiltration of immune cells into the synovium.


Author(s):  
Ozkan Karatas ◽  
Fikret Gevrek

Background: 3,4,5-Trihydroxybenzoic acid, which is also known as gallic acid, is an anti-inflammatory agent who could provide beneficial effects in preventing periodontal inflammation. The present study aimed to evaluate the anti-inflammatory effects of gallic acid on experimental periodontitis in Wistar rats. Alveolar bone loss, osteoclastic activity, osteoblastic activity, and collagenase activity were also determined. Methods: 32 Wistar rats were used in the present study. Study groups were created as following: Healthy control (C,n=8) group; periodontitis (P,n=8) group; periodontitis and 30 mg/kg gallic acid administered group (G30,n=8); periodontitis and 60 mg/kg gallic acid administered group (G60,n=8). Experimental periodontitis was created by placing 4-0 silk sutures around the mandibular right first molar tooth. Morphological changes in alveolar bone were determined by stereomicroscopic evaluation. Mandibles were undergone histological evaluation. Matrix metalloproteinase (MMP)-8, tissue inhibitor of MMPs (TIMP)-1, bone morphogenetic protein (BMP)-2 expressions, tartrate-resistant acid phosphatase (TRAP) positive osteoclast cells, osteoblast, and inflammatory cell counts were determined. Results: Highest alveolar bone loss was observed in the periodontitis group. Both doses of gallic acid decreased alveolar bone loss compared to the P group. TRAP-positive osteoclast cell counts were higher in the P group, and gallic acid successfully lowered these counts. Osteoblast cells also increased in gallic acid administered groups. Inflammation in the P group was also higher than those of C, G30, and G60 groups supporting the role of gallic acid in preventing inflammation. 30 and 60 mg/kg doses of gallic acid decreased MMP-8 levels and increased TIMP-1 levels. BMP levels increased in gallic acid administered groups, similar to several osteoblasts. Conclusion: Present results revealed an anti-inflammatory effect of gallic acid, which was indicated by decreased alveolar bone loss and collagenase activity and increased osteoblastic activity.


Molecules ◽  
2021 ◽  
Vol 26 (13) ◽  
pp. 3913
Author(s):  
Rui-Jie He ◽  
Jun Li ◽  
Yong-Lin Huang ◽  
Ya-Feng Wang ◽  
Bing-Yuan Yang ◽  
...  

Polyphenols, widely distributed in the genus Melastoma plants, possess extensive cellular protective effects such as anti-inflammatory, anti-tyrosinase, and anti-obesity, which makes it a potential anti-inflammatory drug or enzyme inhibitor. Therefore, the aim of this study is to screen for the anti-inflammatory and enzyme inhibitory activities of compounds from title plant. Using silica gel, MCI, ODS C18, and Sephadex LH-20 column chromatography, as well as semipreparative HPLC, the extract of Melastoma normale roots was separated. Four new ellagitannins, Whiskey tannin C (1), 1-O-(4-methoxygalloyl)-6-O-galloyl-2,3-O-(S)-hexahydroxydiphenoyl-β-d-glucose (2), 1-O-galloyl-6-O-(3-methoxygalloyl)-2,3-O-(S)-hexahydroxydiphenoyl-β-d-glucose (3), and 1-O-galloyl-6-O-vanilloyl-2,3-O-(S)-hexahydroxydiphenoyl-β-d-glucose (4), along with eight known polyphenols were firstly obtained from this plant. The structures of all isolates were elucidated by HRMS, NMR, and CD analyses. Using lipopolysaccharide (LPS)-stimulated RAW2 64.7 cells, we investigated the anti-inflammatory activities of compounds 1–4, unfortunately, none of them exhibit inhibit nitric oxide (NO) production, their IC50 values are all > 50 μM. Anti-tyrosinase activity assays was done by tyrosinase inhibition activity screening model. Compound 1 showed weak tyrosinase inhibitory activity with IC50 values of 426.02 ± 11.31 μM. Compounds 2–4 displayed moderate tyrosinase inhibitory activities with IC50 values in the range of 124.74 ± 3.12–241.41 ± 6.23 μM. The structure–activity relationships indicate that hydroxylation at C-3′, C-4′, and C-3 in the flavones were key to their anti-tyrosinase activities. The successful isolation and structure identification of ellagitannin provide materials for the screening of anti-inflammatory drugs and enzyme inhibitors, and also contribute to the development and utilization of M. normale.


Plants ◽  
2021 ◽  
Vol 10 (8) ◽  
pp. 1545
Author(s):  
Hwa-Young Song ◽  
Da-Eun Jeong ◽  
Mina Lee

The aim of this study was to identify the optimal extraction conditions for leaves of Osmanthus fragrans var. aurantiacus. Inhibitory effects of various extracts on NO production were compared. Antioxidant evaluations for total phenol and flavonoid contents were carried out using various extracts of O. fragrans var. aurantiacus leaves obtained under optimal extraction conditions that showed the greatest effect on NO production. The optimal method for extracting O. fragrans var. aurantiacus leaves resulted in an extract named OP OFLE. OP OFLE showed DPPH and ABTS radical scavenging activities in a concentration-dependent manner. Phillyrin (PH) was isolated as a major compound from OP OFLE by HPLC/DAD analysis. OP OFLE and PH reduced inducible nitric oxide (iNOS) and cyclooxygenase (COX)-2 protein expression and downregulated proinflammatory cytokines such as interleukin (IL)-1β, IL-6, IL-8, and tumor necrosis factor (TNF)-α in LPS-stimulated RAW 264.7 and HT-29 cells. To determine the signal pathway involved in the inhibition of NO production, a Western blot analysis was performed. Results showed that OP OFLE decreased phosphorylation of extracellular regulated kinase (pERK) 1/2 and the expression of nuclear factor-kappa B (NF-κB). Our results suggest that extracts of O. fragrans var. aurantiacus leaves and its major components have biological activities such as antioxidative and anti-inflammatory properties.


Separations ◽  
2021 ◽  
Vol 8 (5) ◽  
pp. 57
Author(s):  
Rokayya Sami ◽  
Abeer Elhakem ◽  
Mona Alharbi ◽  
Manal Almatrafi ◽  
Nada Benajiba ◽  
...  

Onions contain high antioxidants compounds that fight inflammation against many diseases. The purpose was to investigate some selected bioactive activities of onion varieties (Yellow, Red, Green, Leek, and Baby). Antioxidant assays and anti-inflammatory activities such as NO production with the addition of some bioactive components were determined and analyzed by using a spectrophotometer. Gas chromatography and mass spectrometry (GC–MS) was used for the volatile compounds, while an Atomic absorption spectrometer was used for mineral determinations. Red variety achieved the highest antioxidant activities. The total flavonoids were between (12.56 and 353.53 mg Quercetin/gin dry weight) (dw) and the total phenol was (8.75–25.73 mg/g dw). Leek, Yellow and Green extracts achieved highly anti-inflammatory values (3.71–4.01 μg/mL) followed by Red and Baby extracts, respectively. The highest contents of sodium, potassium, zinc, and calcium were established for Red onions. Furfuraldehyde, 5-Methyl-2-furfuraldehyde, 2-Methyl-2-pentenal, and 1-Propanethiol were the most predominant, followed by a minor abundance of the other compounds such as Dimethyl sulfide, Methyl allyl disulfide, Methyl-trans-propenyl-disulfide, and Methyl propyl disulfide. The results recommend that these varieties could act as sources of essential antioxidants and anti-inflammatories to decrease inflammation and oxidative stresses, especially red onions that recorded high activities.


2021 ◽  
pp. 096228022110259
Author(s):  
Shintaro Yamamuro ◽  
Tomohiro Shinozaki ◽  
Satoshi Iimuro ◽  
Yutaka Matsuyama

Modern causal mediation theory has formalized several types of indirect and direct effects of treatment on outcomes regarding specific mediator variables. We reviewed and unified distinct approaches to estimate the “interventional” direct and indirect effects for multiple mediators and time-varying variables. This study was motivated by a clinical trial of elderly type-2 diabetic patients in which atorvastatin was widely prescribed to control patients’ cholesterol levels to reduce diabetic complications, including cardiovascular disease. Among atorvastatin’s preventive side-effects (pleiotropic effects), we focus on its anti-inflammatory action as measured by white blood cell counts. Hence, we estimate atorvastatin’s interventional indirect effects through cholesterol lowering and through anti-inflammatory action, and interventional direct effect bypassing these two actions. In our analysis, total effect (six-year cardiovascular disease risk difference) estimated by standard plug-in g-formula of −3.65% (95% confidence interval: −10.29%, 4.38%) is decomposed into indirect effect via low-density lipoprotein cholesterol (−0.90% [−1.91%, −0.07%]), via white blood cell counts (−0.03% [−0.22%, 0.11%]), and direct effect (−2.84% [−9.71%, 5.41%]) by the proposed parametric mediational g-formula. The SAS program and its evaluation via simulated datasets are provided in the Supplemental materials.


Marine Drugs ◽  
2020 ◽  
Vol 19 (1) ◽  
pp. 2
Author(s):  
Gina De La Fuente ◽  
Marco Fontana ◽  
Valentina Asnaghi ◽  
Mariachiara Chiantore ◽  
Serena Mirata ◽  
...  

Inflammation and oxidative stress are part of the complex biological responses of body tissues to harmful stimuli. In recent years, due to the increased understanding that oxidative stress is implicated in several diseases, pharmaceutical industries have invested in the research and development of new antioxidant compounds, especially from marine environment sources. Marine seaweeds have shown the presence of many bioactive secondary metabolites, with great potentialities from both the nutraceutical and the biomedical point of view. In this study, 50%-ethanolic and DMSO extracts from the species C. amentacea var. stricta were obtained for the first time from seaweeds collected in the Ligurian Sea (north-western Mediterranean). The bioactive properties of these extracts were then investigated, in terms of quantification of specific antioxidant activities by relevant ROS scavenging spectrophotometric tests, and of anti-inflammatory properties in LPS-stimulated macrophages by evaluation of inhibition of inflammatory cytokines and mediators. The data obtained in this study demonstrate a strong anti-inflammatory effect of both C. amentacea extracts (DMSO and ethanolic). The extracts showed a very low grade of toxicity on RAW 264.7 macrophages and L929 fibroblasts and a plethora of antioxidant and anti-inflammatory effects that were for the first time thoroughly investigated. The two extracts were able to scavenge OH and NO radicals (OH EC50 between 392 and 454 μg/mL; NO EC50 between 546 and 1293 μg/mL), to partially rescue H2O2-induced RAW 264.7 macrophages cell death, to abate intracellular ROS production in H2O2-stimulated macrophages and fibroblasts and to strongly inhibit LPS-induced inflammatory mediators, such as NO production and IL-1α, IL-6, cyclooxygenase-2 and inducible NO synthase gene expression in RAW 264.7 macrophages. These results pave the way, for the future use of C. amentacea metabolites, as an example, as antioxidant food additives in antiaging formulations as well as in cosmetic lenitive lotions for inflamed and/or damaged skin.


2018 ◽  
Vol 19 (11) ◽  
pp. 3622 ◽  
Author(s):  
Hyeon Nam ◽  
Li Nan ◽  
Byung Choo

Reflux esophagitis (RE) is a gastrointestinal disease caused by the reflux of gastric acid and stomach contents, and it leads to esophageal damage. Therefore, it is necessary to study the improvement of esophageal damage on a RE-induced model. The present study was accomplished to demonstrate the protective effects of a dichloromethane fraction of Geranium koreanum (DGK) plant on esophageal damage in an acute RE rat model. First, we examined the potential of anti-inflammatory effects of various fractions measured by cell cytotoxicity, morphological changes and nitric oxide (NO) production on lipopolysaccharide (LPS)-induced Raw 264.7 macrophage cells. Then, to evaluate the protective effects on RE, rats were partitioned into the following groups: normal control, RE-induced control and RE rats pre-treated with DGK 100 and 200 mg/kg body weight. The esophageal mucosal ulcer ratio was measured by the Image J program and histological changes were examined using a hematoxylin and eosin staining of the esophageal mucosa. The expression of pro-inflammatory proteins, cytokines and tight junction proteins involved in the esophageal mucosal damage were investigated using Western blotting and an enzyme-linked immunosorbent assay (ELISA) kit with esophagus tissue. DGK chemical profile and phenolic contents were analyzed by liquid chromatography-mass spectrometry (LC-MS/MS). The results showed that DGK exhibited anti-inflammatory effects against LPS-stimulated cells by significantly inhibiting NO production. Additionally, the results in vivo showed that improvement effects of DGK on esophageal mucosal damage. The expression of inflammatory proteins involved in nuclear factor κB (NF-κB) signaling pathways and tight junction protein (claudin-4 and -5) were significantly decreased in esophageal mucosa. We found the potential of DGK as source of replacement therapy products for inflammatory and RE disease.


Molecules ◽  
2018 ◽  
Vol 23 (10) ◽  
pp. 2631 ◽  
Author(s):  
Zeyuan Wang ◽  
Jianfeng Cai ◽  
Qing Fu ◽  
Lingping Cheng ◽  
Lehao Wu ◽  
...  

Fifteen unreported compounds in Anemarrhena asphodeloides, iriflophene (3), hostaplantagineoside C (7), tuberoside G (8), spicatoside B (9), platycodin D (14), platycoside A (15), platycodin D2 (16), polygalacin D2 (17), platycodin D3 (18), isovitexin (20), vitexin (21), 3,4-dihydroxyallylbenzene-3-O-α-l-rhamnopyranosyl(1→6)-β-d-glucopyranoside (22), iryptophan (24), adenosine (25), α-d-Glucose monoallyl ether (26), together with eleven known compounds (1, 2, 4–6, 10–13, 19 and 23), were isolated from the rhizomes of Anemarrhena asphodeloides. The chemical structures of these compounds were characterized using HRMS and NMR. The anti-inflammatory activities of the compounds were evaluated by investigating their ability to inhibit LPS-induced NO production in N9 microglial cells. Timosaponin BIII (TBIII) and trans-hinokiresinol (t-HL) exhibited significant inhibitory effects on the NO production in a dose-dependent manner with IC50 values of 11.91 and 39.08 μM, respectively. Immunoblotting demonstrated that TBIII and t-HL suppressed NO production by inhibiting the expressions of iNOS in LPS-stimulated N9 microglial cells. Further results revealed that pretreatment of N9 microglial cells with TBIII and t-HL attenuated the LPS-induced expression tumor necrosis factor (TNF)-α and interleukin-6 (IL-6) at mRNAs and protein levels. Moreover, the activation of nuclear factor-κB (NF-κB) and phosphatidylinositol 3-kinase (PI3K)/Akt signaling pathways were inhibited by TBIII and t-HL, respectively. Our findings indicate that the therapeutic implication of TBIII and t-HL for neurogenerative disease associated with neuroinflammation.


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