scholarly journals The Protective Effects of the Supercritical-Carbon Dioxide Fluid Extract ofChrysanthemum indicumagainst Lipopolysaccharide-Induced Acute Lung Injury in Mice via Modulating Toll-Like Receptor 4 Signaling Pathway

2014 ◽  
Vol 2014 ◽  
pp. 1-13 ◽  
Author(s):  
Xiao-Li Wu ◽  
Xue-Xuan Feng ◽  
Chu-Wen Li ◽  
Xiao-Jun Zhang ◽  
Zhi-Wei Chen ◽  
...  

The supercritical-carbon dioxide fluid extract ofChrysanthemum indicumLinné. (CFE) has been demonstrated to be effective in suppressing inflammation. The aim of this study is to investigate the preventive action and underlying mechanisms of CFE on acute lung injury (ALI) induced by lipopolysaccharide (LPS) in mice. ALI was induced by intratracheal instillation of LPS into lung, and dexamethasone was used as a positive control. Results revealed that pretreatment with CFE abated LPS-induced lung histopathologic changes, reduced the wet/dry ratio and proinflammatory cytokines productions (TNF-α, IL-1β, and IL-6), inhibited inflammatory cells migrations and protein leakages, suppressed the levels of MPO and MDA, and upregulated the abilities of antioxidative enzymes (SOD, CAT, and GPx). Furthermore, the pretreatment with CFE downregulated the activations of NF-κB and the expressions of TLR4/MyD88. These results suggested that CFE exerted potential protective effects against LPS-induced ALI in mice and was a potential therapeutic drug for ALI. Its mechanisms were at least partially associated with the modulations of TLR4 signaling pathways.

2017 ◽  
Vol 2017 ◽  
pp. 1-15 ◽  
Author(s):  
Lie-Qiang Xu ◽  
Xiu-Ting Yu ◽  
Shu-Hua Gui ◽  
Jian-hui Xie ◽  
Xiu-Fen Wang ◽  
...  

Li-Fei-Xiao-Yan prescription (LFXY) has been clinically used in China to treat inflammatory and infectious diseases including inflammatory lung diseases. The present study was aimed at evaluating the potential therapeutic effects and potential mechanisms of LFXY in a murine model of lipopolysaccharide- (LPS-) induced acute lung injury (ALI). In this study, the mice were orally pretreated with LFXY or dexamethasone (positive drug) before the intratracheal instillation of LPS. Our data indicated that pretreatment with LFXY enhanced the survival rate of ALI mice, reversed pulmonary edema and permeability, improved LPS-induced lung histopathology impairment, suppressed the excessive inflammatory responsesviadecreasing the expression of proinflammatory cytokines (TNF-α, IL-1β, and IL-6) and chemokine (MIP-2) and inhibiting inflammatory cells migration, and repressed oxidative stress through the inhibition of MPO and MDA contents and the upregulation of antioxidants (SOD and GSH) activities. Mechanistically, treatment with LFXY significantly prevented LPS-induced TLR4 expression and NF-κB (p65) phosphorylation. Overall, the present study suggests that LFXY protected mice from acute lung injury induced by LPSviainhibition of TLR4/NF-κB p65 activation and upregulation of antioxidative enzymes and it may be a potential preventive and therapeutic agent for ALI in the clinical setting.


2015 ◽  
Vol 2015 ◽  
pp. 1-15 ◽  
Author(s):  
Chu-Wen Li ◽  
Zhi-Wei Chen ◽  
Xiao-Li Wu ◽  
Zhao-Xiao Ning ◽  
Zu-Qing Su ◽  
...  

A standardized traditional Chinese medicine preparation named Yejuhua capsule (YJH) has been clinically used in treatments of various acute respiratory system diseases with high efficacy and low toxicity. In this study, we were aiming to evaluate potential effects and to elucidate underlying mechanisms of YJH against lipopolysaccharide- (LPS-) induced acute lung injury (ALI) in mice. Moreover, the chemical analysis and chromatographic fingerprint study were performed for quality evaluation and control of this drug. ALI was induced by intratracheal instillation of LPS (5 mg/kg) into the lung in mice and dexamethasone (5 mg/kg, p.o.) was used as a positive control drug. Results demonstrated that pretreatments with YJH (85, 170, and 340 mg/kg, p.o.) effectively abated LPS-induced histopathologic changes, attenuated the vascular permeability enhancement and edema, inhibited inflammatory cells migrations and protein leakages, suppressed the ability of myeloperoxidase, declined proinflammatory cytokines productions, and downregulated activations of nuclear factor-κB (NF-κB) and expressions of toll-like receptor 4 (TLR4). This study demonstrated that YJH exerted potential protective effects against LPS-induced ALI in mice and supported that YJH was a potential therapeutic drug for ALI in clinic. And its mechanisms were at least partially associated with downregulations of TLR4/NF-κB pathways.


2015 ◽  
Vol 2015 ◽  
pp. 1-8 ◽  
Author(s):  
Xiaoying Huang ◽  
Jiangfeng Tang ◽  
Hui Cai ◽  
Yi Pan ◽  
Yicheng He ◽  
...  

The present study aimed to investigate the therapeutic effect of monoammonium glycyrrhizinate (MAG) on lipopolysaccharide- (LPS-) induced acute lung injury (ALI) in mice and possible mechanism. Acute lung injury was induced in BALB/c mice by intratracheal instillation of LPS, and MAG was injected intraperitoneally 1 h prior to LPS administration. After ALI, the histopathology of lungs, lung wet/dry weight ratio, protein concentration, and inflammatory cells in the bronchoalveolar lavage fluid (BALF) were determined. The levels of tumor necrosis factor-α(TNF-α) and interleukin-1β(IL-1β) in the BALF were measured by ELISA. The activation of NF-κB p65 and IκB-αof lung homogenate was detected by Western blot. Pretreatment with MAG attenuated lung histopathological damage induced by LPS and decreased lung wet/dry weight ratio and the concentrations of protein in BALF. At the same time, MAG reduced the number of inflammatory cells in lung and inhibited the production of TNF-αand IL-1βin BALF. Furthermore, we demonstrated that MAG suppressed activation of NF-κB signaling pathway induced by LPS in lung. The results suggested that the therapeutic mechanism of MAG on ALI may be attributed to the inhibition of NF-κB signaling pathway. Monoammonium glycyrrhizinate may be a potential therapeutic reagent for ALI.


2017 ◽  
Vol 2017 ◽  
pp. 1-9 ◽  
Author(s):  
Wei Ren ◽  
Zhiwei Wang ◽  
Zhiyong Wu ◽  
Zhipeng Hu ◽  
Feifeng Dai ◽  
...  

Patients with aortic dissection (AD) may present acute lung injury (ALI) that may affect the prognosis. In this study, we aim to investigate the roles and mechanism of IL-22 in the pathogenesis of AD complicated with ALI. Six hundred and twenty-one AD patients were included, and the incidence of ALI and pulmonary CT findings were analyzed. Mouse ALI model was established through AngII, and then IL-22 injection and AG490 were given. The pathological changes, infiltration of inflammatory cells, and expression of STAT3 were determined. For the in vitro experiment, cultivated pulmonary microvascular endothelial cells (PMVECs) were treated by angiotensin II (AngII), followed by treating with IL-22 and/or AG490. The expression and migration of STAT3 was determined. Flow cytometry was carried out to evaluate the apoptosis. IL-22 contributed to the expression of STAT3 in lung tissues and attenuation of ALI. IL-22 obviously inhibited the apoptosis of PMVECs mediated by AngII and downregulated the expression and intranuclear transmission of STAT3. Such phenomenon was completely inhibited upon administration of AG490, an inhibitor of JAK2. Our data showed IL-22 contributed to the inhibition of PMVEC apoptosis mediated by AngII through activating the JAK2/STAT3 signaling pathway, which may attenuate the ALI induced by AngII.


2007 ◽  
Vol 293 (2) ◽  
pp. L446-L452 ◽  
Author(s):  
Takefumi Itoh ◽  
Hiroaki Obata ◽  
Shinsuke Murakami ◽  
Kaoru Hamada ◽  
Kenji Kangawa ◽  
...  

Adrenomedullin (AM), an endogenous peptide, has been shown to have a variety of protective effects on the cardiovascular system. However, the effect of AM on acute lung injury remains unknown. Accordingly, we investigated whether AM infusion ameliorates lipopolysaccharide (LPS)-induced acute lung injury in rats. Rats were randomized to receive continuous intravenous infusion of AM (0.1 μg·kg−1·min−1) or vehicle through a microosmotic pump. The animals were intratracheally injected with either LPS (1 mg/kg) or saline. At 6 and 18 h after intratracheal instillation, we performed histological examination and bronchoalveolar lavage and assessed the lung wet/dry weight ratio as an index of acute lung injury. Then we measured the numbers of total cells and neutrophils and the levels of tumor necrosis factor (TNF)-α and cytokine-induced neutrophil chemoattractant (CINC) in bronchoalveolar lavage fluid (BALF). In addition, we evaluated BALF total protein and albumin levels as indexes of lung permeability. LPS instillation caused severe acute lung injury, as indicated by the histological findings and the lung wet/dry weight ratio. However, AM infusion attenuated these LPS-induced abnormalities. AM decreased the numbers of total cells and neutrophils and the levels of TNF-α and CINC in BALF. AM also reduced BALF total protein and albumin levels. In addition, AM significantly suppressed apoptosis of alveolar wall cells as indicated by cleaved caspase-3 staining. In conclusion, continuous infusion of AM ameliorated LPS-induced acute lung injury in rats. This beneficial effect of AM on acute lung injury may be mediated by inhibition of inflammation, hyperpermeability, and alveolar wall cell apoptosis.


1994 ◽  
Vol 266 (3) ◽  
pp. L209-L216 ◽  
Author(s):  
M. P. D'Ortho ◽  
P. H. Jarreau ◽  
C. Delacourt ◽  
I. Macquin-Mavier ◽  
M. Levame ◽  
...  

Matrix metalloproteinases (MMPs) and elastase are proteolytic enzymes specifically directed against extracellular matrix (ECM) components. They are secreted by inflammatory cells and may consequently contribute to the lesions of the ECM observed during acute pulmonary edema. We therefore evaluated the MMP and elastase activities, which are secreted by cultured alveolar macrophages (AMACs) and polymorphonuclear neutrophils (PMNs) and present in the bronchoalveolar lavage (BAL) fluid in a guinea pig model of acute lung injury induced by intratracheal instillation of lipopolysaccharide (LPS). The control group was given 0.9% NaCl. 24 h after instillation, a BAL was performed, the BAL fluid was separated from the cells by centrifugation, and AMACs and PMNs were separately cultured for 24 h. In BAL fluid from LPS-treated guinea pigs, we found 1) an increase in free gelatinase activity, tested on [3H]gelatin (0.7 +/- 0.2 micrograms.200 microliters BAL fluid-1.48 h-1 vs. 0.2 +/- 0.1 in controls, P < 0.05), and 2) increased total gelatinase activities, as assessed by zymography. The molecular masses of the major gelatinase species found in BAL fluid by zymography were 92 and 68 kDa. The 92-kDa gelatinase was secreted by both AMACs and PMNs, as demonstrated by zymography of their respective culture media. When tested on [3H]elastin, the elastase activity of BAL fluid of LPS-treated animals exhibited no increase, but when tested on a synthetic peptidic substrate [N-succinyl-(L-alanine)3-p-nitro anilide (SLAPN)], increased elastase-like activity was observed (from 17 +/- 4 nmol of SLAPN.200 microliters BAL fluid-1.24 h-1 in control group to 34 +/- 8 in LPS group, P < 0.05). This increase was attributable to the activity of a metalloendopeptidase that was inhibited by the metal chelator EDTA but not by the specific tissue inhibitor of MMPs.


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