Myricetin Attenuates LPS-induced Inflammation in RAW 264.7 Macrophages and Mouse Models

AbstractBackgroundMyricetin has been demonstrated to inhibit inflammation in a variety of diseases, but little is known about its characters in acute lung injury (ALI). In this study, we aimed to investigate the protective effects of myricetin on inflammation in lipopolysaccharide (LPS)-stimulated RAW 264.7 cells and a LPS-induced lung injury model.MethodsSpecifically, we investigated its effects on lung edema and histological damage by lung W/D weight ratio, HE staining and Evans Blue dye. Then macrophage activation was detected by evaluating the TNF-α, IL-6 and IL-1β mRNA and protein iNOS and COX-2. Myricetin was used to detect the impact on the inflammatory responses in LPS-induced RAW264.7 cells with the same manners in mouse model. Finally, NF-κB and MAPK signaling pathways were investigated with Western blot assay in LPS-induced RAW264.7 cells.ResultsMyricetin significantly inhibited the production of the pro-inflammatory cytokines in vitro and in vivo. The in vivo experiments showed that pretreatment with Myricetin markedly attenuated the development of pulmonary edema, histological severities and macrophage activation in mice with ALI. The underlying mechanisms were further demonstrated in vitro that myricetin exerted an anti-inflammatory effect through suppressing the NF-κB p65 and AKT activation in NF-κB pathway and JNK, p-ERK and p38 in mitogen-activated protein kinases signaling pathway.ConclusionMyricetin alleviated ALI by inhibiting macrophage activation, and inhibited inflammation in vitro and in vivo. It may be a potential therapeutic candidate for the prevention of inflammatory diseases.

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Ulinastatin Activated The ERK5/Mer Signaling Pathway To Promote Macrophage Efferocytosis And Ameliorate Lung Inflammation

10.21203/rs.3.rs-1091035/v1 ◽

2021 ◽

Author(s):

Jinju Li ◽

Rongge Shao ◽

Qiuwen Xie ◽

XueKe Du

Keyword(s):

Lung Injury ◽

Signaling Pathway ◽

Lung Inflammation ◽

Raw264.7 Cells ◽

Inflammatory Factors ◽

Inflammatory Factor ◽

Dependent Manner ◽

Anti Inflammatory

Abstract Purpose:Ulinastatin (UTI) is an endogenous protease inhibitor with potent anti-inflammatory, antioxidant and organ protective effects. The inhibitor has been reported to ameliorate inflammatory lung injury but precise mechanisms remain unclear. Methods: An in vivo model of lung injury has been constructed by intratracheal infusion of lipopolysaccharide (LPS). The number of neutrophils and the phagocytosis of apoptotic neutrophils were observed by Diff- Quick method. Lung injury was observed by HE staining .BALF cells were counted by hemocytometer and concentrations of protein plus inflammatory factors were measured with a BCA test kit. During in vitro experiments, RAW264.7 cells were pretreated with UTI (1000 and 5000U/ mL), stained with CellTrackerTM Green B0DIPYTM and HL60 cells added with UV-induced apoptosis and PKH26 Red staining. The expression of ERK5\Mer related proteins was detected by western blot and immunofluorescence.Results: An in vivo model of lung injury has been constructed by intratracheal infusion of lipopolysaccharide (LPS). UTI treatment enhanced the phagocytotic effect of mouse alveolar macrophages on neutrophils, alleviated lung lesions, decreased the pro-inflammatory factor and total protein content of BALF and increased levels of anti-inflammatory factors. in vitro experiments ，UTI enhanced the phagocytosis of apoptotic bodies by RAW264.7 cells in a dose-dependent manner. Increased expression levels of ERK5 and Mer by UTI were shown by Western blotting and immunofluorescence.Conclusions: UTI mediated the activation of the ERK5/Mer signaling pathway, enhanced phagocytosis of neutrophils by macrophages and improved lung inflammation. The current study indicates potential new clinical approaches for accelerating the recovery from lung inflammation.

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Evidence for reprogramming of monocytes into reparative alveolar macrophages in vivo by targeting PDE4b

AJP Lung Cellular and Molecular Physiology ◽

10.1152/ajplung.00145.2021 ◽

2021 ◽

Author(s):

Ian Rochford ◽

Jagdish Chandra Joshi ◽

Rayees Sheikh ◽

Mumtaz Anwar ◽

Md Zahid Akhter ◽

...

Keyword(s):

Lung Injury ◽

Alveolar Macrophages ◽

Lung Edema ◽

Rna Seq ◽

Activation Of Transcription ◽

The Impact ◽

Camp Levels ◽

Phosphodiesterase 4B ◽

Lung Vascular Permeability

Increased lung vascular permeability and neutrophilic inflammation are hallmarks of acute lung injury. Alveolar macrophages (AMϕ), the predominant sentinel cell type in the airspace, die in massive numbers while fending off pathogens. Recent studies indicate that the AMϕ pool is replenished by airspace-recruited monocytes, but the mechanisms instructing the conversion of recruited monocytes into reparative AMϕ remain elusive. Cyclic AMP (cAMP) is a vascular barrier protective and immunosuppressive second messenger in the lung. Here, we subjected mice expressing GFP under the control of the Lysozyme-M promoter (LysM-GFP mice) to the LPS model of rapidly resolving lung injury to address the impact of mechanisms determining cAMP levels in AMϕ and regulation of mobilization of the reparative AMϕ-pool. RNA-seq analysis of flow-sorted Mϕ identified phosphodiesterase 4b (PDE4b) as the top LPS-responsive cAMP-regulating gene. We observed that PDE4b expression markedly increased at the time of peak injury (4 h) and then decreased to below the basal level during the resolution phase (24 h). Activation of transcription factor NFATc2 was required for transcription of PDE4b in Mϕ. Inhibition of PDE4 activity at the time of peak injury, using i.t. rolipram, increased cAMP levels, augmented the reparative AMϕ pool, and resolved lung injury. This response was not seen following conditional depletion of monocytes, thus establishing airspace-recruited PDE4b-sensitive monocytes as the source of reparative AMϕ. Interestingly, adoptive transfer of rolipram-educated AMϕ into injured mice resolved lung edema. We propose suppression of PDE4b as an effective approach to promote reparative AMϕ generation from monocytes for lung repair.

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A Subanesthetic Dose of Isoflurane during Postconditioning Ameliorates Zymosan-Induced Neutrophil Inflammation Lung Injury and Mortality in Mice

Mediators of Inflammation ◽

10.1155/2013/479628 ◽

2013 ◽

Vol 2013 ◽

pp. 1-14 ◽

Cited By ~ 5

Author(s):

Hui Wang ◽

Jing Fan ◽

Nan-lin Li ◽

Jun-tang Li ◽

Shi-fang Yuan ◽

...

Keyword(s):

Lung Injury ◽

Nuclear Translocation ◽

Inflammatory Responses ◽

Weight Ratio ◽

Polymorphonuclear Neutrophils ◽

Mouse Lung ◽

Endothelial Adhesion Molecule ◽

Primary Mouse

Anesthetic isoflurane (ISO) has immunomodulatory effects. In the present study, we investigated whether a subanesthetic dose of ISO (0.7%) protected against zymosan (ZY) induced inflammatory responses in the murine lung and isolated neutrophils. At 1 and 6 hrs after ZY administration intraperitoneally, ISO was inhaled for 1 hr, and 24 hrs later, lung inflammation and injury were assessed. We found that ISO improved the survival rate of mice and mitigated lung injury as characterized by the histopathology, wet-to-dry weight ratio, protein leakage, and lung function index. ISO significantly attenuated ZY-induced lung neutrophil recruitment and inflammation. This was suggested by the downregulation of (a) endothelial adhesion molecule expression and myeloperoxidase (MPO) activity in lung tissue and polymorphonuclear neutrophils (b) chemokines, and (c) proinflammatory cytokines in BALF. Furthermore, ZY-induced nuclear translocation and DNA-binding activity of NF-κB p65 were also reduced by ISO. ISO treatment inhibited iNOS expression and activity, as well as subsequent nitric oxide generation. Consistent with thesein vivoobservations,in vitrostudies confirmed that ISO blocked NF-κB and iNOS activation in primary mouse neutrophils challenged by ZY. These results provide evidence that 0.7% ISO ameliorates inflammatory responses in ZY-treated mouse lung and primary neutrophils.

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Tanreqing Inhibits LPS-Induced Acute Lung Injury In Vivo and In Vitro Through Downregulating STING Signaling Pathway

Frontiers in Pharmacology ◽

10.3389/fphar.2021.746964 ◽

2021 ◽

Vol 12 ◽

Author(s):

Yu-Qiong He ◽

Can-Can Zhou ◽

Jiu-Ling Deng ◽

Liang Wang ◽

Wan-Sheng Chen

Keyword(s):

Oxidative Stress ◽

Acute Lung Injury ◽

Lung Injury ◽

Signaling Pathway ◽

Inflammatory Responses ◽

Lung Edema ◽

Protective Effects ◽

And Oxidative Stress

Acute lung injury (ALI) is a common life-threatening lung disease, which is mostly associated with severe inflammatory responses and oxidative stress. Tanreqing injection (TRQ), a Chinese patent medicine, is clinically used for respiratory-related diseases. However, the effects and action mechanism of TRQ on ALI are still unclear. Recently, STING as a cytoplasmic DNA sensor has been found to be related to the progress of ALI. Here, we showed that TRQ significantly inhibited LPS-induced lung histological change, lung edema, and inflammatory cell infiltration. Moreover, TRQ markedly reduced inflammatory mediators release (TNF-α, IL-6, IL-1β, and IFN-β). Furthermore, TRQ also alleviated oxidative stress, manifested by increased SOD and GSH activities and decreased 4-HNE, MDA, LDH, and ROS activities. In addition, we further found that TRQ significantly prevented cGAS, STING, P-TBK, P-P65, P-IRF3, and P-IκBα expression in ALI mice. And we also confirmed that TRQ could inhibit mtDNA release and suppress signaling pathway mediated by STING in vitro. Importantly, the addition of STING agonist DMXAA dramatically abolished the protective effects of TRQ. Taken together, this study indicated that TRQ alleviated LPS-induced ALI and inhibited inflammatory responses and oxidative stress through STING signaling pathway.

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Cissus subtetragona Planch. Ameliorates Inflammatory Responses in LPS-induced Macrophages, HCl/EtOH-induced Gastritis, and LPS-induced Lung Injury via Attenuation of Src and TAK1

Molecules ◽

10.3390/molecules26196073 ◽

2021 ◽

Vol 26 (19) ◽

pp. 6073

Author(s):

Laily Rahmawati ◽

Nur Aziz ◽

Jieun Oh ◽

Yo Han Hong ◽

Byoung Young Woo ◽

...

Keyword(s):

Acute Lung Injury ◽

Lung Injury ◽

Mouse Models ◽

Molecular Mechanisms ◽

Inflammatory Responses ◽

Raw264.7 Cells ◽

Acute Gastritis ◽

Anti Inflammatory

Several Cissus species have been used and reported to possess medicinal benefits. However, the anti-inflammatory mechanisms of Cissus subtetragona have not been described. In this study, we examined the potential anti-inflammatory effects of C. subtetragona ethanol extract (Cs-EE) in vitro and in vivo, and investigated its molecular mechanism as well as its flavonoid content. Lipopolysaccharide (LPS)-induced macrophage-like RAW264.7 cells and primary macrophages as well as LPS-induced acute lung injury (ALI) and HCl/EtOH-induced acute gastritis mouse models were utilized. Luciferase assays, immunoblotting analyses, overexpression strategies, and cellular thermal shift assay (CETSA) were performed to identify the molecular mechanisms and targets of Cs-EE. Cs-EE concentration-dependently reduced the secretion of NO and PGE2, inhibited the expression of inflammation-related cytokines in LPS-induced RAW264.7 cells, and decreased NF-κB- and AP-1-luciferase activity. Subsequently, we determined that Cs-EE decreased the phosphorylation events of NF-κB and AP-1 pathways. Cs-EE treatment also significantly ameliorated the inflammatory symptoms of HCl/EtOH-induced acute gastritis and LPS-induced ALI mouse models. Overexpression of HA-Src and HA-TAK1 along with CETSA experiments validated that inhibited inflammatory responses are the outcome of attenuation of Src and TAK1 activation. Taken together, these findings suggest that Cs-EE could be utilized as an anti-inflammatory remedy especially targeting against gastritis and acute lung injury by attenuating the activities of Src and TAK1.

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Between Fate Choice and Self-Renewal—Heterogeneity of Adult Neural Crest-Derived Stem Cells

Frontiers in Cell and Developmental Biology ◽

10.3389/fcell.2021.662754 ◽

2021 ◽

Vol 9 ◽

Author(s):

Anna L. Höving ◽

Beatrice A. Windmöller ◽

Cornelius Knabbe ◽

Barbara Kaltschmidt ◽

Christian Kaltschmidt ◽

...

Keyword(s):

Stem Cells ◽

Stem Cell ◽

Neural Crest ◽

Current Knowledge ◽

Mapk Signaling ◽

Cellular Heterogeneity ◽

Self Renewal ◽

The Impact

Stem cells of the neural crest (NC) vitally participate to embryonic development, but also remain in distinct niches as quiescent neural crest-derived stem cell (NCSC) pools into adulthood. Although NCSC-populations share a high capacity for self-renewal and differentiation resulting in promising preclinical applications within the last two decades, inter- and intrapopulational differences exist in terms of their expression signatures and regenerative capability. Differentiation and self-renewal of stem cells in developmental and regenerative contexts are partially regulated by the niche or culture condition and further influenced by single cell decision processes, making cell-to-cell variation and heterogeneity critical for understanding adult stem cell populations. The present review summarizes current knowledge of the cellular heterogeneity within NCSC-populations located in distinct craniofacial and trunk niches including the nasal cavity, olfactory bulb, oral tissues or skin. We shed light on the impact of intrapopulational heterogeneity on fate specifications and plasticity of NCSCs in their niches in vivo as well as during in vitro culture. We further discuss underlying molecular regulators determining fate specifications of NCSCs, suggesting a regulatory network including NF-κB and NC-related transcription factors like SLUG and SOX9 accompanied by Wnt- and MAPK-signaling to orchestrate NCSC stemness and differentiation. In summary, adult NCSCs show a broad heterogeneity on the level of the donor and the donors’ sex, the cell population and the single stem cell directly impacting their differentiation capability and fate choices in vivo and in vitro. The findings discussed here emphasize heterogeneity of NCSCs as a crucial parameter for understanding their role in tissue homeostasis and regeneration and for improving their applicability in regenerative medicine.

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Klotho Alleviates Lung Injury Caused by Paraquat via Suppressing ROS/P38 MAPK-Regulated Inflammatory Responses and Apoptosis

Oxidative Medicine and Cellular Longevity ◽

10.1155/2020/1854206 ◽

2020 ◽

Vol 2020 ◽

pp. 1-13

Author(s):

Zhiqiang Zhang ◽

Qing Nian ◽

Gang Chen ◽

Shuqing Cui ◽

Yuzhen Han ◽

...

Keyword(s):

Lung Injury ◽

Cell Viability ◽

P38 Mapk ◽

Inflammatory Responses ◽

A549 Cells ◽

Control Group ◽

Ros Production ◽

The Impact

Acute lung injury (ALI) induced by paraquat (PQ) progresses rapidly with high mortality; however, there is no effective treatment, and the specific mechanism is not well understood. The antiaging protein klotho (KL) has multiple functions and exerts significant influences on various pathophysiological processes. This work evaluated the impact of KL on PQ-induced ALI and investigated its underlying mechanisms. As for in vivo research, C57BL/6 mice were treated with PQ (30 mg/kg) intraperitoneal (IP) injection to create a toxicity model of ALI (PQ group). The mice were divided into control group, KL group, PQ group, and PQ+KL group. For in vitro experiment, A549 cells were incubated with or without KL and then treated in the presence or absence of PQ for 24 h. In vivo result indicated that KL reduced the mortality, reduced IL-1β and IL-6 in the bronchoalveolar lavage fluid (BALF), attenuated ALI, and decreased apoptosis in situ. In vitro result revealed that KL significantly improved cell viability, reduced the levels of IL-1β and IL-6 in culture supernatants, suppressed cell apoptosis, inhibited caspase-3 activation, and enhanced mitochondrial membrane potential (ΔΨm) after PQ treatment. Besides, KL effectively abated reactive oxygen species (ROS) production, improved GSH content, and lowered lipid peroxidation in PQ-exposed A549 cells. Further experiments indicated that phosphorylated JNK and P38 MAPK was increased after PQ treatment; however, KL pretreatment could significantly lower the phosphorylation of P38 MAPK. Suppression of P38 MAPK improved cell viability, alleviated inflammatory response, and reduced apoptosis-related signals; however, it had no obvious effect on the production of ROS. Treatment with N-acetylcysteine (NAC), a classic ROS scavenger, could suppress ROS production and P38 MAPK activation. These findings suggested that KL could alleviate PQ-caused ALI via inhibiting ROS/P38 MAPK signaling-regulated inflammatory responses and mitochondria-dependent apoptosis.

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Effect of intravenous catalase on the pulmonary vascular response to endotoxemia in goats

Journal of Applied Physiology ◽

10.1152/jappl.1988.64.2.697 ◽

1988 ◽

Vol 64 (2) ◽

pp. 697-704 ◽

Cited By ~ 9

Author(s):

R. J. Maunder ◽

R. K. Winn ◽

J. M. Gleisner ◽

J. Hildebrandt ◽

J. M. Harlan

Keyword(s):

Acute Lung Injury ◽

Lung Injury ◽

Endothelial Damage ◽

In Vivo Model ◽

Lung Edema ◽

Experimental Sepsis ◽

Base Line ◽

In Vitro Systems

Neutrophils have been implicated in the pathogenesis of acute lung injury associated with clinical and experimental sepsis. Data from in vitro systems and experimental animals have suggested that neutrophil-derived oxidants, particularly H2O2, may be primarily responsible for endothelial damage, vasoconstriction, and lung edema. With the use of endotoxin infusion as an in vivo model of sepsis we tested the hypothesis that pretreatment with catalase, a peroxide scavenger, would ameliorate the resultant changes in pulmonary vasoconstriction and lung fluid balance. Paired experiments were performed in 16 goats with chronic lung lymph fistulas. One group of animals (n = 7) received endotoxin first alone and then again, several days later, after pretreatment with Ficoll-linked catalase. As a control, identical experiments were performed in a separate group (n = 6) with Ficoll-linked albumin substituted for Ficoll-catalase. A third group (n = 3) was given endotoxin alone and then again during a continuous infusion of catalase. Plasma and lymph levels of catalase were comparable to or exceeded those previously shown to be completely protective in isolated perfused lung preparations and in vitro systems. Endotoxin caused neutropenia, pulmonary arterial hypertension, decreased cardiac output, and increases in lymph flow to approximately three times base line, with a return of all variables toward control values by 6 h. Catalase pretreatment produced no significant differences in any of these variables. These experiments do not support a role for H2O2 as a mediator of acute lung injury due to endotoxemia.

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Viola yedoensis Liposoluble Fraction Ameliorates Lipopolysaccharide-Induced Acute Lung Injury in Mice

The American Journal of Chinese Medicine ◽

10.1142/s0192415x12500747 ◽

2012 ◽

Vol 40 (05) ◽

pp. 1007-1018 ◽

Cited By ~ 17

Author(s):

Wen Li ◽

Jun-Yun Xie ◽

Hong Li ◽

Yun-Yi Zhang ◽

Jie Cao ◽

...

Keyword(s):

Acute Lung Injury ◽

Lung Injury ◽

Chemical Constituents ◽

Chinese Herb ◽

Weight Ratio ◽

Acute Injury ◽

Myeloperoxidase Activity ◽

Proinflammatory Mediators

Viola yedoensis is a component of traditional Chinese herb medicine for inflammatory diseases. Chemical constituents of V. yedoensis have been shown to possess antibacterial, anti-HIV, and anticoagulant effects in experimental research; however, their anti-inflammatory properties remain to be demonstrated. In this study, a mouse model of lipopolysaccharide (LPS)-induced acute lung injury was used to investigate the effect of petroleum ether fraction of V. yedoensis (PEVY) on inflammation in vivo. After being shown to have anti-complementary activity in vitro, PEVY was orally administered to the mice at doses of 2, 4, and 8 mg/kg. Treatment with PEVY significantly decreased the wet-to-dry weight ratio of the lung, total cells, red blood cells, protein concentration, and myeloperoxidase activity in bronchoalveolar lavage fluid. PEVY markedly attenuated lung injury with improved lung morphology and reduced complement deposition. In addition, PEVY suppressed the expression of pro-inflammatory cytokines, TNF-α, IL-1β, and IL-6. Taken together, PEVY protects the lung from acute injury, potentially via inhibiting the activation of the complement system and excessive production of proinflammatory mediators.

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