Fasudil,an inhibitor of Rho-associated coiled-coil kinase,attenuates hyperoxia-induced pulmonary fibrosis in neonatal rats

Background: Oxygen therapy is important during the management of high-risk neonatal infants, such as those with preterm birth, low birth weight, and asphyxia. However, prolonged exposure to high oxygen concentrations can readily lead to diffuse nonspecific inflammation, which promotes airway remodeling and pulmonary fibrosis. The Rho/Rho-associated coiled-coil kinase (Rho/ROCK) signaling pathway plays an important role in numerous developmental and proliferative diseases. This study was performed to determine the efficacy of ROCK inhibitor fasudil in blocking the development of hyperoxia-induced lung injury and fibrosis in neonatal rats. Methods: Neonatal rats were randomly divided into four groups: air + saline group, air + fasudil group, hyperoxia + saline group, and hyperoxia + fasudil group. The hyperoxia + saline and Hyp + fasudil groups were exposed to 95% oxygen for 21 days and administered intraperitoneal saline or fasudil once daily. The air + saline and air + fasudil group were exposed to 21% oxygen (room air) and administered the same volume of intraperitoneal saline or fasudil. Results: Fasudil-treated rats exhibited improved histopathological changes and decreased lung hydroxyproline content. Fasudil attenuated the protein level of alpha-smooth muscle actin, transforming growth factor-β1, and connective tissue growth factor. Additionally, fasudil reduced the activation of ROCK1 and myosin phosphatase targeting subunit 1 protein in the Rho/ROCK signaling pathway. Conclusions: Fasudil may be a potentially effective therapeutic drug for hyperoxia-induced pulmonary fibrosis.     

Modulation of LPS-Stimulated Pulmonary Inflammation by Borneol in Murine Acute Lung Injury Model

The object of our study is to investigate the protective effects of Borneol on lipopolysaccharide (LPS)-induced acute lung injury (ALI) in mice. To determine the effects of Borneol on the histopathological changes in mice with ALI, inflammatory cell count in bronchoalveolar lavage fluid (BALF) and lung wet/dry weight ratio were measured in LPS-challenged mice, and lung histopathologic changes observed via paraffin section were assessed. Next, cytokine production induced by LPS in BALF and RAW 264.7 cells was measured by enzyme-linked imunosorbent assay (ELISA). To further study the mechanism of Borneol-protective effects on ALI, nuclear factor-kappaB (NF-κB) and mitogen-activated protein kinases (MAPKs) pathways were investigated. In the present study, Borneol obviously alleviated pulmonary inflammation by reducing inflammatory infiltration, histopathological changes, descended cytokine production, and pulmonary edema initiated by LPS. Furthermore, Borneol significantly suppressed phosphorylation of NF-κB/P65, IκBa, p38, JNK, and ERK. Taken together, our results suggest that Borneol suppressed inflammatory responses in LPS-induced acute lung injury through inhibition of the NF-κB and MAPKs signaling pathways. Borneol may be a promising potential preventive agent for acute lung injury treatment.     

Role for macrophage migration inhibitory factor in acute respiratory distress syndrome

The critical role of macrophage migration inhibitory factor (MIF) in mediating inflammatory lung injury in acute respiratory distress syndrome (ARDS) has been raised recently. The present study has identified enhanced MIF protein expression in alveolar capillary endothelium and infiltrating macrophages in lung tissues from ARDS patients. The possibility that MIF up-regulates its synthesis in an autocrine fashion in ARDS was tested using cultured endothelial cells stimulated with MIF and a murine model of lipopolysaccharide (LPS)-induced acute lung injury. MIF induced significant MIF and tumour necrosis factor (TNF)-alpha synthesis in cultured endothelial cells and the effect was blocked by neutralizing anti-MIF antibody. A similar blocking effect was observed when MIF-stimulated endothelial cells were pretreated with neutralizing anti-TNF-alpha antibody or glucocorticoid, supporting the notion that MIF induced TNF-alpha production via an amplifying pro-inflammatory loop. Treatment with anti-MIF or glucocorticoid effectively attenuated pulmonary pathology and the synthesis of MIF or TNF-alpha in mice with LPS-induced acute lung injury. Mildly augmented expression of aquaporin 1 (AQP1) was also detected in alveolar capillary endothelium in ARDS. In vitro studies revealed that both MIF and TNF-alpha induced a small increase of AQP1 synthesis in cultured endothelial cells. These findings suggest that MIF plays a crucial pathological role leading to alveolar inflammation in ARDS. Anti-MIF and early glucocorticoid therapy may represent a novel therapeutic approach for reducing alveolar inflammation in ARDS.     

1,8-Cineol Attenuates LPS-Induced Acute Pulmonary Inflammation in Mice

Eucalyptol, also known as 1,8-cineol, is a monoterpene and has been shown to exert anti-inflammatory and antioxidant effect. It is traditionally used to treat respiratory disorders due to its secretolytic properties. In the present study, we evaluated the effect of 1,8-cineol on pulmonary inflammation in a mouse model of acute lung injury. We found that 1,8-cineol significantly decreased the level of TNF-α and IL-1β, and increased the level of IL-10 in lung tissues after acute lung injury induced by lipopolysaccharide (LPS). It also reduced the expression of nuclear factor kappa B (NF-κB) p65 and toll-like receptor 4 (TLR4), and myeloperoxidase activity in lung tissues. In addition, 1,8-cineol reduced the amounts of inflammatory cells in bronchoalveolar lavage fluid (BALF), including neutrophils and macrophages, and significantly decreased the protein content in BALF and the lung wet/dry weight (W/D) ratio. Its effect on LPS-induced pulmonary inflammation was associated with suppression of TLR4 and NF-κB expressions. Our results provide evidence that 1,8-cineol inhibits acute pulmonary inflammation, indicating its potential for the treatment of acute lung injury.     

Schistosoma egg antigens suppress LPS-induced inflammation in human IMR-90 cells by modulation of JAK/STAT1 signaling

BackgroundThe regulation of the balance between inflammatory and anti-inflammatory events during the treatment of pulmonary infection is very important. Soluble Schistosoma egg antigens (SEA) can effectively inhibit the expression of cytokines during hepatic acute inflammation. However, the mechanisms by which these proteins suppress the inflammatory responses in lung cells remain unclear. The purpose of this study was to investigate the ability of SEA to inhibit pulmonary inflammation.MethodsThe effects of SEA were investigated in LPS-treated lung IMR-90 cells. The involvement of the JAK/STAT-1 signaling pathway in these effects was evaluated by employing CBA assays, quantitative polymerase chain reaction, and western blotting experiments.ResultsPretreatment of IMR-90 cells with appropriate concentrations of SEA protected cells against the cytotoxic effects of LPS-induced inflammation in a time-dependent manner. SEA pretreatment significantly attenuated the LPS-induced activation of the JAK/STAT1 signaling pathway, including the upregulation of JAK1/2 and STAT1, as well as the production of inflammatory cytokines. The level of phosphorylated STAT1 gradually declined in response to increasing concentrations of SEA. Based on these findings, we hypothesize that SEA-induced anti-inflammatory effects initiate with the downregulation of the IFN-γ-JAK-STAT1 signaling pathway, resulting in the attenuation of LPS-induced inflammation in IMR-90 cells.ConclusionOur study is the first to demonstrate the anti-inflammatory activity of SEA in an in vitro model of pulmonary inflammation, involving the modulation of JAK/STAT1 signaling. We propose SEA as potential therapeutic or preventive agents for the selective suppression of STAT1 and the control of inflammatory response in lung IMR-90 cells.     

Attenuation of endotoxin-induced acute lung injury by the Rho-associated kinase inhibitor, Y-27632

A small GTPase, Rho, plays key roles in cell adhesion, motility, and contraction after stimulation. Among Rho effectors isolated, the family of Rho-associated coiled-coil-forming protein kinases (ROCK) is implicated in Rho-mediated cell adhesion and smooth muscle contraction. The effect of a specific inhibitor of ROCK, Y-27632, was evaluated in a murine model of acute lung injury induced by intravenous injection of Escherichia coli endotoxin (lipopolysaccharide [LPS]). Lung edema was evaluated by measuring extravascular leakage of radio-labeled serum albumin, and neutrophil emigration into the lung parenchyma by morphometric observation and measuring myeloperoxidase activity. Pretreatment with Y-27632 attenuated both lung edema and neutrophil emigration after LPS. We also measured albumin transfer through cultured endothelial cell monolayers on a porous filter. Tumor necrosis factor-alpha significantly increased albumin transfer, which was attenuated by pretreatment with Y-27632. Fluorescence microscopy revealed that morphologic changes in endothelial cells induced by tumor necrosis factor-alpha were inhibited by Y-27632. In contrast, the increased fraction of neutrophils with polymerized actin after formyl-methionyl-leucyl-phenylalanine was not altered by Y-27632. These data suggest that ROCK may play an important role in the pathogenesis of LPS-induced lung injury and that ROCK inhibition could attenuate cytoskeletal rearrangement of endothelial cells, leading to decreased neutrophil emigration into the lung parenchyma.     

The role of aquaporin-1 (AQP1) expression in a murine model of lipopolysaccharide-induced acute lung injury

A murine model of lipopolysaccharide (LPS)-induced acute lung injury (ALI) was used to evaluate whether aquaporin-1 (AQP1) is involved in lung inflammation and lung edema formation. Swiss strain mice (n = 122) had LPS (5 mg/kg) instilled intratracheally (IT), and were then treated with either 0.9 % saline or dexamethasone (5 mg/kg/day). Mice were euthanized at 2 days and 7 days after treatment. Inflammatory cytokines (TNF-alpha, IL-6), protein concentration in bronchoalveolar lavage (BAL) fluid, lung wet-to-dry weight ratio, histology, immunohistochemistry, and AQP1 Western blot were performed. Lung wet-to-dry weight ratio and lung vascular permeability were also measured in the AQP1 knockout mice (n = 9) that received IT LPS (5 mg/kg) at 2 days. Intratracheal instillation of LPS produced a severe lung injury at 2 days, characterized by elevation of TNF-alpha, IL-6 in the BAL fluid, and by histological changes consistent with increased lung vascular permeability and neutrophil infiltration. AQP1-immunoreactivity in the pulmonary capillary endothelium was reduced at 2 days and 7 days. Administration of dexamethasone improved LPS-induced ALI and retained expression of AQP1. However, depletion of AQP1 did not affect lung edema formation, lung vascular permeability, or lung histology. The results suggest that although AQP1 expression is decreased after lung injury, depletion of AQP1 does not alter lung inflammation and lung edema induced by LPS.     

Vagal Efferent Fiber Stimulation Ameliorates Pulmonary Microvascular Endothelial Cell Injury by Downregulating Inflammatory Responses

Electrical stimulation of the vagus nerve may have positive effects on many inflammatory diseases. This study determined the beneficial effects of vagus nerve stimulation and the mechanisms by which it attenuates lipopolysaccharide (LPS)-induced acute lung injury (ALI). Rats were intraperitoneally injected with 10 mg/kg LPS to induce ALI. The results showed that vagus nerve stimulation could improve lung injury, as evidenced by remarkable reductions in lung edema (wet-to-dry weight ratio), neutrophil infiltration (myeloperoxidase activity), and pulmonary permeability [total number of cells and protein concentrations in bronchoalveolar lavage fluid (BALF)]. In addition, vagus nerve stimulation not only decreased the expressions of Src-suppressed C kinase substrate and E-selectin proteins in lung tissue but also effectively attenuated the concentrations of the proinflammatory cytokines tumor necrosis factor-α, interleukin-1β, and interleukin-6 in BALF. These suggest that vagus nerve stimulation is a suitable treatment for LPS-induced ALI and indicate that it helps ameliorate pulmonary microvascular endothelial cell injury by downregulating inflammatory responses.     

Ellagic acid protects against LPS-induced acute lung injury through inhibition of nuclear factor kappa B,proinflammatory cytokines and enhancement of interleukin-10

Ellagic acid is a naturally occurring polyphenolic compound which is found in many fruits, nut galls and plant extracts. In the present study, we explored the ability of ellagic acid to modulate lipopolysaccharides (LPS) response using macrophage-mediated inflammatory conditions and acute lung injury (ALI). The data showed that ellagic acid reduced TNF-α, IL-6 and IL-1β secretions, enhance IL-10 production by LPS-stimulated RAW 264.7 macrophages in vitro. In murine ALI model, mice were treated with ellagic acid prior to LPS challenge. The data showed that ellagic acid possess a protective effect on LPS-induced ALI in mice. The underlying mechanism may be through shocking the NF-κB pathway to attenuate the nonspecific pulmonary inflammation induced by LPS administration.     

常山酮通过CD14/ NF-κB 通路调控LPS 诱导的大鼠急性肺损伤免疫系统紊乱

目的:探究常山酮(Halofuginone,HF)对脂多糖(Lipopolysaccharide,LPS)诱导的大鼠急性肺损伤(Acute lung injury,ALI)免疫系统紊乱的作用及机制。方法:用LPS 复制大鼠ALI 模型并腹腔注射HF,HE 染色检测肺病理损伤情况, TUNEL 检测凋亡小体数量,ELISA 检测炎症因子含量,流式细胞术检测CD14 含量,Western blot 检测CD14/ NF鄄资B 通路蛋白的 表达。结果:HF 可改善LPS 诱导的肺组织损伤,并能显著抑制ALI 大鼠凋亡小体的形成;同时,HF 可显著抑制LPS 诱导的炎 症因子(IL-1β、IL-6、IL-18)的分泌;此外,HF 能明显减少ALI 大鼠外周血CD14+ 细胞含量;HF 还可显著下调CD14/ NF鄄资B 通 路标记蛋白(CD14、TLR4、NF-κB p65)的表达。结论:HF 可通过CD14/ NF鄄资B 通路调控LPS 诱导的大鼠ALI 免疫系统紊乱。     

Tubeimoside-1 attenuates LPS-induced inflammation in RAW 264.7 macrophages and mouse models

Abstract

Context: Acute lung injury (ALI), characterized by severe hypoxemia, pulmonary edema and neutrophil accumulation in the lung, is a common clinical problem associated with significant morbidity and mortality in shock, sepsis, ischemia reperfusion, etc.

Objective: In this study, we aimed at investigating the protective effect of tubeimoside-1 (TBMS1) on inflammation in lipopolysaccharide (LPS)-stimulated RAW 264.7 cells and a LPS-induced in vivo lung injury model.

Materials and methods: We evaluated the effect of TBMS1 on LPS-induced production of tumor necrosis factor (TNF)-α, interleukin (IL)-6 and IL-1β in the culture supernatants of RAW 264.7 cells by enzyme-linked immunosorbent assay. LPS (0.5?mg/kg) was instilled intranasally in phosphate-buffered saline to induce ALI, and the severity of pulmonary injury was evaluated 6?h after LPS challenge.

Results: TBMS1 significantly inhibited the production of the pro-inflammatory cytokines, TNF-α, IL-6 and IL-1β in vitro and in vivo. Pretreatment with TBMS1 markedly attenuated the development of pulmonary edema, histological severities and inflammatory cells infiltration in mice with ALI. In addition, we further demonstrated that TBMS1 exerts an anti-inflammatory effect in vivo model of ALI through suppression of IκB activation and p38/extracellular signal-regulated kinase mitogen-activated protein kinases signaling in a dose-dependent manner.

Discussion and conclusion: Overall, our data suggest that TBMS1 inhibits inflammation both in vitro and in vivo, and may be a potential therapeutic candidate for the prevention of inflammatory diseases.     

MiR-802 alleviates lipopolysaccharide-induced acute lung injury by targeting Peli2

Introduction

Acute respiratory distress syndrome (ARDS) is a life-threatening medical condition. It is characterized by serious lung inflammation or injury. Characterizing novel miRNAs implicated in ARDS pathogenesis may provide new therapeutic strategy for managing ARDS.

Methods

We employed LPS-induced lung injury model to profile miRNAs associated with ARDS. We isolated one miRNA candidate and characterized its role in lipopolysaccharide (LPS)-induced proinflammatory cytokine production in lung macrophages. We further evaluated its functional role in ARDS model by assessing histological change, neutrophil activation, tissue permeability and tumor necrosis factor alpha (TNFα) production. We also characterized its downstream target using luciferase assay, Western blotting, enzyme-linked immunosorbent assay and cell inflammation assay.

Results

Microarray profiling revealed miR-802 was significantly downregulated in ARDS mouse model. LPS-induced miR-802 downregulation was confirmed in lung macrophages. Overexpression of miR-802 significantly suppressed LPS-induced inflammatory cytokine production in vitro and alleviates LPS-induced acute lung injury in vivo. Peli2 was identified as a downstream target of miR-802 and found upregulated in ARDS model. Overexpressing Peli2 abolished the antagonizing effect of miR-802 on LPS-mediated inflammatory response.

Conclusion

MiR-802 carried a protective role against LPS-induced acute lung injury by downregulating Peli2. MiR-802/Peli2 axis may act as intervening targets to manage ARDS.

     

Polydatin attenuates ipopolysaccharide-induced acute lung injury in rats

Anti-inflammatory and anti-apoptotic effects of polydatin (PD) have been demonstrated in our previous studies. Recently, we have found that PD treatment can ameliorate burn-induced acute lung injury (ALI). In the present study, we hypothesized that PD may provide protective effect against LPS-induced ALI through reducing inflammation and apoptosis. Rats were respectively pretreated with PD at doses of 15, 30 and 45 mg/kg weight, followed by intratracheal administration of lipopolysaccharide (LPS). LPS-challenged rats exhibited significant lung injury characterized by the deterioration of histopathology, pulmonary microvascular hyperpermeability, wet-to-dry weight ratio, and oxygenation index, which was attenuated by PD (30 and 45 mg/kg) treatment. Moreover, PD (30 and 45 mg/kg) treatment inhibited LPS-induced inflammatory response, as evidenced by the downregulation of lung myeloperoxidase activity, total cells and PMNs in bronchoalveolar lavage fluid, and the systemic levels of the pro-inflammatory cytokines. Furthermore, PD (30 and 45 mg/kg) treatment remarkably improved LPS-induced increase in TUNEL (deoxynucleotidyl transferase dUTP nick end labeling) staining-positive cells, caspase 3 activity, Bax over-expression and Bcl-2 down-expression. In conclusion, these results demonstrate that PD (30 and 45 mg/kg) treatment attenuates LPS-induced ALI through reducing lung inflammation and apoptosis.     

Role of Protease Activated Receptor 2 in Experimental Acute Lung Injury and Lung Fibrosis

Protease activated receptor 2 (PAR2) is widely‐distributed (lung, liver, kidney, etc.) and expressed by variety of cells (i.e. leukocytes, epithelial cells, endothelial cells, and fibroblast). PAR2 may participate in many pathological processes, such as, inflammation, injury, as well as fibrosis. Therefore, in this study, we tested whether PAR2 would exert a role in acid‐induced acute lung injury, E. coli pneumonia, bleomycin‐induced acute lung injury and fibrosis. Acid, E. coli, or bleomycin were intratracheally instilled into the lungs of both wildtype and PAR2 knockout mice to detect differences in pulmonary edema, lung vascular permeability, lung fibrosis, and other parameters. Knockout of PAR2 did not affect the extent of pulmonary edema and lung vascular permeability in acid‐induced acute lung injury. Also, both activation of PAR2 in the airspaces of the lung and deletion of PAR2 did not alter the magnitude of pulmonary edema and lung vascular permeability in E. coli pneumonia. Finally, PAR2 deficiency did not affect the severity of lung inflammation and lung fibrosis in bleomycin‐induced acute lung injury and lung fibrosis models. Thus, PAR2 does not appear to play a critical role in the pathogeneses of experimental acid‐induced acute lung injury, E. coli pneumonia, and bleomycin‐induced acute lung injury and pulmonary fibrosis in mice. Anat Rec, 2009. © 2009 Wiley‐Liss, Inc.     

丹参酮ⅡA激活Nrf2/Nox4通路减轻脂多糖诱导的小鼠肺炎和纤维化

目的研究丹参酮ⅡA(Tan ⅡA)对脂多糖诱导小鼠肺炎和纤维化影响,探讨其潜在的作用机制。方法30只8周龄雄性C57BL/6小鼠,随机分成对照组、脂多糖(LPS)组和LPS+Tan ⅡA组。采用尾静脉注射LPS制作小鼠肺炎和纤维化动物模型,术后给予Tan ⅡA干预,每日一次,连续2周,实验第4周处死所有小鼠,收集血清和肺组织标本。采用HE染色检测肺组织炎症改变,Masson染色观察肺组织纤维化程度,ELISA检测血清IL-1β、TNF-α和IL-10蛋白表达,采用Western blot技术检测肺组织Nrf2、Nox4、Nqo1和Ho-1蛋白表达。结果与对照组相比,LPS组小鼠肺脏重量、肺脏/体重比显著增加,肺组织水肿、炎细胞浸润和纤维化明显加重,血清促炎蛋白IL-1β、TNF-α显著升高,抑炎蛋白IL-10表达下降(P<0.05)。Tan ⅡA处理显著减轻LPS导致的小鼠肺脏重量、肺脏/体重比,减轻肺水肿、炎细胞浸润和纤维化,减低血清IL-1β、TNF-α表达水平,升高IL-10表达水平。此外,Nrf2和Nox4蛋白表达水平LPS组高于对照组,Nqo1和Ho-1蛋白表达水平低于对照组,而Tan ⅡA处理可以上调Nrf2、Nqo1和Ho-1蛋白,降低Nox4蛋白表达水平(P<0.05)。结论Tan ⅡA减轻LPS诱发的小鼠炎症和纤维化,与激活Nrf2/Nox4通路相关。     

Dose-related protection from nickel-induced lung injury in transgenic mice expressing human transforming growth factor-alpha

To determine the role of transforming growth factor-alpha (TGF-alpha) in protecting the lung from aerosolized nickel injury, transgenic mouse lines expressing human TGF-alpha in the pulmonary epithelium, under control of the human surfactant protein-C gene promoter, were tested. Higher expressing TGF-alpha transgenic mouse lines, expressing distinct levels of TGF-alpha, survived longer than nontransgenic control mice. Increased survival correlated with levels of TGF-alpha expression in the lung. After 72 h of nickel exposure (70 microg Ni/m3), transgenic lines with intermediate levels of the TGF-alpha expression demonstrated attenuation of lung injury. The highest expressing line (line 28) demonstrated reduced lung inflammation and edema, reduced lung wet-to-dry weight ratios, decreased bronchoalveolar lavage (BAL) protein and neutrophils, reduced interleukin (IL)-1beta, interleukin-6, and macrophage inflammatory protein-2, and maintained surfactant protein-B (SP-B) levels compared with nontransgenic controls. In the TGF-alpha transgenic mouse model, TGF-alpha protects against nickel-induced acute lung injury, at least in part, by attenuating the inflammatory response, reducing pulmonary edema, and preserving levels of SP-B.     

Cavidine Ameliorates Lipopolysaccharide-Induced Acute Lung Injury <Emphasis Type="Italic">via</Emphasis> NF-κB Signaling Pathway <Emphasis Type="Italic">in vivo</Emphasis> and <Emphasis Type="Italic">in vitro</Emphasis>

Acute lung injury (ALI) is characterized by widespread inflammation in the lungs and alveolar-capillary destruction, causing high morbidity and mortality. Cavidine, isolated from Corydalis impatiens, have been exhibited to have potent anti-inflammatory effects in previous studies. The purpose of this study was to evaluate the protective effect of cavidine on lipopolysaccharide (LPS)-induced ALI and to enunciate the underlying in vivo and in vitro mechanisms. Mice were intraperitoneally administrated with cavidine (1, 3, or 10 mg/kg) at 1 and 12 h, prior to the induction of ALI by intranasal administration of LPS (30 mg/kg). Blood samples, lung tissues, and bronchoalveolar lavage fluid (BALF) were harvested after LPS challenge. Furthermore, we used LPS-induced lung epithelial cells A549 to examine the mechanism of cavidine to lung injury. The results showed that pretreatment with cavidine significantly decreased lung wet-to-dry weight (W/D) ratio, reduced pro-inflammatory cytokine levels including TNF-α and IL-6 in BALF and serum from LPS-stimulated mice, and attenuated lung histopathological changes. In addition, western blot results showed that cavidine inhibited the phosphorylation of nuclear factor-kappaB (NF-κB) p65 and IκBα induced by LPS. In conclusion, our results demonstrate that cavidine protects against LPS-induced acute lung injury in mice via inhibiting of pro-inflammatory cytokine TNF-α and IL-6 production and NF-κB signaling pathway activation. Taken together, cavidine may be useful for the prevention and treatment of pulmonary inflammatory diseases, such as ALI.     

Fisetin Alleviates Lipopolysaccharide-Induced Acute Lung Injury via TLR4-Mediated NF-κB Signaling Pathway in Rats

Acute lung injury (ALI), a common component of systemic inflammatory disease, is a life-threatening condition without many effective treatments. Fisetin, a natural flavonoid from fruits and vegetables, was reported to have wide pharmacological properties such as anti-inflammatory, antioxidant, and anticancer activities. The aim of this study was to detect the effects of fisetin on lipopolysaccharide (LPS)-induced acute lung injury and investigate the potential mechanism. Fisetin was injected (1, 2, and 4 mg/kg, i.v.) 30 min before LPS administration (5 mg/kg, i.v.). Our results showed that fisetin effectively reduced the inflammatory cytokine release and total protein in bronchoalveolar lavage fluids (BALF), decreased the lung wet/dry ratios, and obviously improved the pulmonary histology in LPS-induced ALI. Furthermore, fisetin inhibited LPS-induced increases of neutrophils and macrophage infiltration and attenuated MPO activity in lung tissues. Additionally, fisetin could significantly inhibit the Toll-like receptor 4 (TLR4) expression and the activation of NF-κB in lung tissues. Our data indicates that fisetin has a protective effect against LPS-induced ALI via suppression of TLR4-mediated NF-κB signaling pathways, and fisetin may be a promising candidate for LPS-induced ALI treatment.     

Artesunate Protects LPS-Induced Acute Lung Injury by Inhibiting TLR4 Expression and Inducing Nrf2 Activation

Artesunate, a derivative of artemisinin, has been reported to have anti-inflammatory property. However, few studies showed the protective effects of artesunate on lung injury. In this study, we aimed to investigate the effects of artesunate on LPS-induced lung injury in mice. The mice were treated with artesunate 1 h before or after LPS treatment. The effects of artesunate on lung MPO activity and malondialdehyde (MDA) content were detected. The lung wet/dry radio and the numbers of inflammatory cells in BALF were also measured. ELISA was used to evaluate the levels of TNF-α, IL-1β, and IL-6 in BALF. Western blot analysis was adapted to detect TLR4 and Nrf2 signaling pathways. The results showed that artesunate protected against LPS-induced ALI by decreasing the numbers of inflammatory cells, lung edema, MPO activity, and MDA content. Furthermore, artesunate significantly inhibited the levels of TNF-α, IL-1β, and IL-6. Artesunate also inhibited LPS-induced IL-6 and IL-8 production in the A549 cells. In addition, artesunate dose-dependently suppressed LPS-induced TLR4 expression and NF-κB activation. The expression of Nrf2 and HO-1 were also up-regulated by artesunate. The data suggest that artesunate possesses anti-inflammatory and anti-oxidant properties against LPS-induced ALI via inhibiting TLR4 signaling pathway and activating Nrf2 signaling pathway.     

法舒地尔通过抑制兔尿道成纤维细胞Rho/ROCK通路激活减少尿道损伤后狭窄的发生

目的:研究法舒地尔对创伤后兔尿道狭窄发生的影响及机制,观察兔尿道成纤维细胞活力、迁移以及细胞外基质合成情况。方法:利用显微外科技术建立兔尿道创伤动物模型,分为5组:假手术组,手术组,不同剂量(3 mg/kg、10 mg/kg、30 mg/kg)法舒地尔组,术后3个月逆行尿道造影测量狭窄直径。从兔尿道瘢痕组织提取成纤维细胞进行传代培养,培养液中分别加入TGF-β1(10μg/L)和/或法舒地尔(12.5μmol/L,25μmol/L,50μmol/L)。MTT比色法检测细胞活力;用Transwell小室实验检测细胞迁移能力;Western blot法检测各组Rho相关激酶(ROCK)、α-平滑肌肌动蛋白(α-SMA)以及胶原蛋白Ⅰ和Ⅲ的表达情况。结果:法舒地尔显著减少尿道损伤后狭窄发生(P0.05)。随着法舒地尔浓度的增加,成纤维细胞的活力受到抑制,细胞迁移能力逐渐减弱,ROCK、α-SMA以及胶原蛋白Ⅰ和Ⅲ的表达受到抑制;法舒地尔对兔尿道成纤维细胞外基质及ROCK表达起抑制作用,并呈剂量依赖性(P0.05)。结论:法舒地尔可以通过下调TGF-β1诱导的兔尿道成纤维细胞Rho/ROCK通路,抑制细胞外基质形成,减少尿道损伤后狭窄的发生。