Histopathological Changes In Lung Tissues Research Articles

The expression of Nrf2 in the lung tissue of rats with acute diquat poisoning and the distribution of diquat in lungs

Objective: To investigate the expression of nuclear factor erythroid 2-related factor 2 (Nrf2) in the lung tissue of rats with acute diquat (DQ) poisoning and the distribution of diquat in lungs. Methods: Fifty-four fasted male Wistar rats were randomized into control group (n=6) and exposure group (n=48) . According to the time point, the exposure group was divided into 2 h, 4 h, 12 h, 1 d, 3 d, 7 d, 11 d and 14 d groups with 6 rats in each group. Exposure groups were administered 11.55 mg/kg DQ (1 ml/100 g BW) by single-dose of intragastric administration, while the control group rats were given normal saline. The histopathological changes of lung tissue of rats in each group were observed. The expression of nrf2 in lung tissue was detected by immunohistochemistry, and the diquat concentration in lungs was determined by high performance liquid chromatography-tandem mass spectrometry (HPLC-MS) . Results: In the exposure group, DQ was detected in lungs on 2 hours after poisoning. The concentration of DQ in lung tissue decreased gradually over time, and there was no accumulation in lung tissue. The histopathological changes of lung tissue were not obvious in the early stage of poisoning. The injury was the most serious on the 3rd day, a large number of inflammatory cells could be seen in alveolar cavity and lung stroma, and the pathological injury of lung tissue began to be alleviated on the 7th day. The results of immunohistochemistry showed that Nrf2 was mainly expressed in the nucleus of pulmonery cells. The expression of Nrf2 in the exposure group was significantly higher than the control group. The expression of Nrf2 increased significantly at the 12th hour (P<0.05) , reached the peak on the 3rd day (P<0.05) . There was no difference between the control group and the 14th day (P>0.05) . Conclusion: There was no accumulation of DQ in the lung tissue for a long time, and there was a hysteresis in lung injury induced by redox reaction of DQ. Nrf2 was highly expressed in the lung tissue of rats with acute DQ poisoning, which was correlated with histopathology injury of lung tissue, suggesting that Nrf2 plays an important role in antagonizing acute lung injury induced by DQ.

Recombinant PAL/PilE/FlaA DNA vaccine provides protective immunity against Legionella pneumophila in BALB/c mice

BackgroundLegionella pneumophila (L.pneumophila), a Gram-negative small microorganism, causes hospital-acquired pneumonia especially in immunocompromised patients. Vaccination may be an effective method for preventing L.pneumophila infection. Therefore, it is necessary to develop a better vaccine against this disease. In this study, we developed a recombinant peptidoglycan-associated lipoprotein (PAL)/type IV pilin (PilE)/lagellin (FlaA) DNA vaccine and evaluated its immunogenicity and efficacy to protect against L.pneumophila infection.ResultsAccording to the results, the expression of PAL, PilE, FlaA proteins and PAL/PilE/FlaA fusion protein in 293 cells was confirmed. Immunization with PAL/PilE/FlaA DNA vaccine resulted in highest IgG titer and strongest cytotoxic T-lymphocyte (CTL) response. Furthermore, the histopathological changes in lung tissues of mice challenged with a lethal dose of L.pneumophila were alleviated by PAL/PilE/FlaA DNA vaccine immunization. The production of T-helper-1 (Th1) cytokines (IFNγ, TGF-α, and IL-12), and Th2 cytokines (IL-4 and IL-10) were promoted in PAL/PilE/FlaA DNA vaccine group. Finally, immunization with PAL/PilE/FlaA vaccine raised the survival rate of mice to 100% after challenging with a lethal dose of L.pneumophila for 10 consecutive days.ConclusionsOur study suggests that the newly developed PAL/PilE/FlaA DNA vaccine stimulates strong humoral and cellular immune responses and may be a potential intervention on L.pneumophila infection.

Macrophage Activity and Histopathological Differences of Lung Tissue on Sequential Co-infections of Heligmosomoides Polygyrus Nematode on Mycobacterium Tuberculosis Infection

Background: Tuberculosis is a chronic infection caused by Mycobacterium tuberculosis, a facultative intracellular parasite, that can be eliminated by cellular immunity played by macrophages. It has become a debate whether the co-infection of nematodes will affect the immune response of macrophages towards mycobacterium infection. Objective: To reveal macrophage activity and histopathological difference of lung tissue in sequential coinfection of Heligmosomoides Polygyrus towards Mycobacterium tuberculosis infection. Method: This study used 49 mice divided into 7 treatment groups with Mycobacterium tuberculose infection by inhalation and Heligmosomoides polygyrus orally within 8 and 16 weeks, and observed by immunohistochemical staining. Result: Infection for 8 weeks showed polarization of macrophages towards M1 macrophage, whereas in 16 weeks, the macrophage polarization more towards M2 macrophages, supported by histopathological changes of lung tissue: peribronchiolitis, perivaskulitis, alveolitis, and granuloma formation with counts of acid-resistant germs +3. There was a difference of expression of arginase1 to each group (p &lt;0.001) and there was a difference of T CD4+ Th1 lymphocyte (p &lt;0.001). Conclusion: There is a difference in macrophage activity in lung tissue; however, it does not cause different levels of histopathological changes in lung tissue and does not affect the immune response to Mycobacterium tuberculosis infection.

Marrow-derived mesenchymal stem cells regulate the inflammatory response and repair alveolar type II epithelial cells in acute lung injury of rats.

ObjectiveWe investigated the effect of untransplantable bone marrow-derived mesenchymal stem cells (BMSCs) in acute lung injury (ALI) and whether BMSCs attenuate damage of lipopolysaccharide (LPS) to alveolar type II epithelial cells (AECIIs).MethodsALI models were prepared by nebulizing LPS and then BMSCs were infused 1 hour later. We observed histopathological changes of lung tissue and evaluated inflammatory exudation by the wet/dry weight ratio, bronchiolar lavage fluid cell count, and protein concentration determination. Inflammatory and vascular factors were detected by immunohistochemistry and western blotting. For in vitro experiments, AECIIs were stimulated with 10 μg/mL LPS for 4 hours and then BMSCs were seeded in transit inserts to co-culture for 24 hours. The activity of AECIIs was detected.ResultsIn the LPS + BMSCs group, histopathological examination showed that the degree of lung injury was significantly reduced compared with the LPS group. Protein expression of inflammatory and vascular factors was significantly lower with treatment. Optical density values and cell viability of the LPS + BMSCs group were significantly higher than those of the LPS group.ConclusionsUntransplanted-BMSCs can inhibit the inflammatory response in ALI and promote repair of AECIIs. This might be due to substances secreted by BMSCs and interaction between these substances.

Fructus mume Protects Against Cigarette Smoke Induced Chronic Cough Guinea Pig.

Fructus mume was recorded in the Chinese Pharmacopoeia and traditional Chinese medical books for chronic cough, but the effect and related constituents are still unknown. Thus, we investigated the protect effects and the relevant constituents of F. mume in a guinea pig model with chronic cough induced by cigarette smoke (CS). The organic acids and polysaccharides in F. mume were detected by high performance liquid chromatography, gel permeation chromatography, and gas chromatography-mass spectrometry. The guinea pigs were orally administrated with vehicle or the water extract of Fructus mume (FW) during the 14 days of CS exposure. Citric acid induced coughs were automatically measured by Buxco system. The differential cells in bronchoalveolar lavage fluid (BALF) and histopathological changes in lung tissue were assessed by hematoxylin and eosin staining. The tumor necrosis factor alpha (TNF-α) and interleukin-8 (IL-8) levels in lung tissue were detected via enzyme-linked immunosorbent assay. The mucus productions in tracheas were determined with Alcian blue-periodic acid Schiff staining. The results suggested relatively high concentration of citric acid, chlorogenic acid, and neochlorogenic acid in F. mume, and high proportion of galactose and glucose and lower molecular weight of polysaccharides. Administration of FW significantly reduced the cough frequency, decreased inflammatory cells in BALF and lung tissue, and attenuated the thickening of airway epithelium and submucosa compared with CS-exposure group. Moreover, the overproduction of TNF-α and IL-8 in lung tissues, and mucus in central airways of CS-induced guinea pigs was markedly inhibited by FW. The extract could also protect against CS exposure-induced chronic cough in guinea pigs by reducing coughs, airways inflammation, and mucus overproduction.

Endothelial-platelet interactions in influenza-induced pneumonia: A potential therapeutic target.

Every year, influenza viruses spread around the world, infecting the respiratory systems of countless humans and animals, causing illness and even death. Severe influenza infection is associated with pulmonary epithelial damage and endothelial dysfunction leading to acute lung injury (ALI). There is evidence that an aggressive cytokine storm and cell damage in lung capillaries as well as endothelial/platelet interactions contribute to vascular leakage, pro-thrombotic milieu and infiltration of immune effector cells. To date, treatments for ALI caused by influenza are limited to antiviral drugs, active ventilation or further symptomatic treatments. In this review, we summarize the mechanisms of influenza-mediated pathogenesis, permissive animal models and histopathological changes of lung tissue in both mice and men and compare it with histological and electron microscopic data from our own group. We highlight the molecular and cellular interactions between pulmonary endothelium and platelets in homeostasis and influenza-induced pathogenesis. Finally, we discuss novel therapeutic targets on platelets/endothelial interaction to reduce or resolve ALI.

Roles of the mammalian target of rapamycin (mTOR) signaling pathway in the repair of hyperoxia-induced acute lung injury.

Rapamycin inhibits the mammalian target of rapamycin (mTOR) activity and has been proven effective for the treatment of lung injury. The objective of this study was to investigate the roles of the mTOR pathway and its inhibitor rapamycin in the repair of hyperoxia-induced acute lung injury (ALI). Firstly, premature rat lung fibroblast L929 cells were cultured under different oxygen concentrations (40%, 60%, and 90%). At day 3, 7 and 14 after exposure, MTT assay and flow cytometry were used to evaluate the effect of oxygen stress on cell viability and apoptosis of L929 cells, respectively. Secondly, microscopy, MTT assay and flow cytometry was used to investigate the effect of 10 nM rapamycin on 90% O2 exposed L929 cells. We also used small interfering RNAs (siRNAs) to abrogate the expression of mTOR in 90% O2 exposed L929 cells, and then evaluated the apoptosis and cell viability using flow cytometry and the MTT assay, respectively. In addition, western blot was used to detect the protein expression of Bcl-2, p53, TGF-β and connective tissue growth factor (CTGF). A hyperoxia-induced lung injury model was established in Sprague Dawley (SD) rats in order to evaluate the histopathological changes in lung tissues and expression of the mTOR pathway and fibrosis related factors. Exposure to 40%, 60% or 90% oxygen all significantly inhibited the growth of L929 cells. Application of 10 nM rapamycin was found to effectively promote apoptosis of 90% O2 exposed L929 cells. In addition, mTOR siRNA promoted the apoptosis and inhibited the growth of L929 cells. Rapamycin inhibited the activation of the mTOR signaling pathway, down-regulated the expression of downstream proteins p70S6K and 4EBP1, reduced the collagen deposition and the production of fibrosis-inducing factors, including TGF-β and CTGF in hyperoxia-induced lung injury rats. Rapamycin may be useful for the treatment of hyperoxia-induced acute lung injury (ALI) by inhibiting the activation of mTOR signaling pathway.

Myxopyrum serratulum ameliorates airway inflammation in LPS-stimulated RAW 264.7 macrophages and OVA-induced murine model of allergic asthma

Ethnopharmacological relevanceMyxopyrum serratulum A. W. Hill. (Oleaceae) is a traditionally used Indian medicinal plant for the treatment of cough, asthma and many other inflammatory diseases. Aim of the studyIn this study, the protective effects of M. serratulum on airway inflammation was investigated in ovalbumin (OVA)-induced murine model of allergic asthma and lipopolysaccharide (LPS)-stimulated inflammation in RAW 264.7 murine macrophages, and the possible mechanisms were elucidated. Materials and methodsThe phytochemicals present in the methanolic leaf extract of M. serratulum (MEMS) were identified by reverse phase high performance liquid chromatography (RP-HPLC) analysis. In vitro anti-inflammatory activity of MEMS were evaluated by estimating the levels of nitric oxide (NO), reactive oxygen species (ROS) and cytokines (IL-1α, IL-1β, IL-2, IL-4, IL-6, IL-10, IL-12, IL-17A, IFN-γ, TNF-α, G-CSF and GM-CSF) in LPS-stimulated RAW 264.7 macrophages. In vivo anti-asthmatic activity of MEMS was studied using OVA-induced murine model. Airway hyperresponsiveness (AHR), was measured; total and differential cell counts, eosinophil peroxidase (EPO), prostaglandin E2 (PGE2), NO, ROS, and cytokines (IL-4, IL-5 and IL-13), were estimated in bronchoalveolar lavage fluid (BALF). Serum total IgE level was measured; and the histopathological changes of lung tissues were observed. The expressions of cyclooxygenase-2 (COX-2) and inducible nitric oxide synthase (iNOS) in lung tissue homogenates were detected by Western blot. ResultsThe chromatographic analysis of MEMS identified the presence of gallic acid, protocatechuic acid, catechin, ellagic acid, rutin, p-coumaric acid, quercetin, naringenin and apigenin. MEMS (125 and 250 μg/mL) dose-dependently reduced the levels of NO, ROS and pro-inflammatory cytokines in LPS-stimulated RAW 264.7 macrophages. MEMS (200 and 400 mg/kg, p.o.) significantly (p < 0.05) alleviated AHR; number of inflammatory cells, EPO, PGE2, NO, ROS, and cytokines (IL-4, IL-5 and IL-13) in BALF; serum total IgE and the histopathological changes associated with lung inflammation. Western blot studies showed that MEMS substantially suppressed COX-2 and iNOS protein expressions in the lung tissues of OVA-sensitized/challenged mice. ConclusionsThe present study corroborates for the first time the ameliorative effects of MEMS on airway inflammation by reducing the levels of oxidative stress, pro-inflammatory cytokines and inhibiting COX-2, iNOS protein expressions, thereby validating the ethnopharmacological uses of M. serratulum.

Total extract of Xin Jia Xuan Bai Cheng Qi decoction inhibits pulmonary fibrosis via the TGF-β/Smad signaling pathways in vivo and in vitro.

PurposePulmonary fibrosis (PF) is a common clinical disease, which results in serious respiratory impairment. Xin Jia Xuan Bai Cheng Qi Decoction (XJXBCQ) is a traditional prescription commonly used in treating lung diseases. We investigate the effect of XJXBCQ against PF and its mechanism via the regulation of TGF-β1/Smad in vitro and in vivo.Materials and methodsXJXBCQ was first extracted and probed for chemical characterization. An PF model in vitro and in vivo was established in rats and in MRC-5 cells. In bleomycin (BLM)-induced rats model, lung function such as peak expiratory flow (PEF), minute ventilation (MV) and hydroxyproline (HYP) were measured; histopathological changes of lung tissue and TGF-β1 in peripheral blood of rats were detected. TGF-β receptor, Smad2 and its phosphorylation expression were tested by Western blot assay in rats model. Then the effects of XJXBCQ on TGF-β1/Smad signal pathway were assessed by Western blot analysis in vitro, and IL-17A and IL-25 levels were evaluated by ELISA in vivo.ResultsOur results showed that XJXBCQ significantly enhanced the lung functions, such as PEF, MV and HYP, by reducing the expression level of lung inflammatory cytokine and the content and fibrosis of lung collagen. Moreover, XJXBCQ effectively inhibited TGF-β1, Smad2 and its phosphorylation expression, and the activation of Smad7 in vitro and in vivo. Furthermore, XJXBCQ had an inhibitory effect on the α-smooth muscle actin (α-SMA) and fibronectin (Fn) in vitro and downregulated IL-17A and IL-25 by inhibiting the activation of TGF-β1/Smad signaling pathway in vitro and in vivo. Further, XJXBCQ effectively inhibitied ventilation volume and peak expiratory content remodeling and hydroxyproline content through inhibition of TGF-βRⅡ, Smad2 and its phosphorylation expression, and activation of Smad7 in vivo.ConclusionXJXBCQ extract had an anti-PF effect in vitro and in vivo, which could be attributed to the inhibition of the expression of p-Smad2 and increase in the expression of Smad7 by regulating the TGF-β1/Smad activity.

Baicalin alleviated APEC-induced acute lung injury in chicken by inhibiting NF-κB pathway activation

Bacterial pneumonia is a leading cause of death in the animal husbandry. Acute lung injury (ALI), most often seen as a part of systemic inflammatory process, characterized by progressive hypoxemia, edema, and neutrophil accumulation in the lung. Baicalin has been reported to inhibit inflammatory response, but its role in ALI remains unknown. The purpose of our study was to determine the protective effect and possible mechanism of baicalin against avian pathogenic Escherichia coli (APEC)-induced ALI in chicken. Chickens were conditioned with baicalin 1 week before intratracheally instilled with APEC. Then, chickens were sacrificed by CO2 inhalation 12 h later and the lung tissues were collected for examining histopathological changes, wet/dry (W/D) ratio, myeloperoxidase (MPO) activity, levels of pro-inflammatory cytokines and activation of NF-κB signaling pathway. The results showed that pre-treatment of chickens with baicalin significantly alleviated the death rate, histopathological changes in lung tissues. The W/D ratio, MPO activity and production of cytokines, such as IL-1β, TNF-α, IL-6 of lung tissues were also decreased following treatment with baicalin. Furthermore, the mechanism responsible for these effects was attributed to the inhibitory effect of baicalin on nuclear factor-κB (NF-κB) signaling activation. These data thus support the application of baicalin as a potential medicine for the treatment of E. coli-induced ALI by regulating NF-κB signaling pathway.

Discovery of 3-(Indol-5-yl)-indazole Derivatives as Novel Myeloid Differentiation Protein 2/Toll-like Receptor 4 Antagonists for Treatment of Acute Lung Injury.

Acute lung injury (ALI) is often caused by systemic inflammatory responses. Targeting the myeloid differentiation protein 2/toll-like receptor 4 (MD2-TLR4) complex may be a promising way to treat Gram-negative bacterial-induced inflammatory disorders. In this study, we report the design and synthesis of a new series of 3-(indol-5-yl)-indazoles, which were evaluated for their anti-inflammatory activities in macrophages. Among the analogues generated, the promising 3-(indol-5-yl)-indazole analogue 22m inhibited lipopolysaccharide (LPS)-induced expression of tumor necrosis factor alpha (TNF-α) and interleukin-6 (IL-6) in macrophages with IC50 values of 0.89 and 0.53 μM, respectively. Compound 22m was then identified as an MD2-TLR4 antagonist in suppressing LPS-induced inflammatory responses. In vivo administration of 22m significantly inhibited macrophage infiltration and ameliorated histopathological changes in lung tissues of LPS-challenged mice. Our studies have identified a new 3-(indol-5-yl)-indazole, 22m, as a potent MD2-TLR4 inhibitor and lay the groundwork for future drug development of anti-inflammatory agents for the treatment of ALI.

Base promoted synthesis of novel indole-dithiocarbamate compounds as potential anti-inflammatory therapeutic agents for treatment of acute lung injury

An efficient protocol for highly chemoselective introduction of dithiocarbamate groups to nitrogen position of indoles with bis(dialkylaminethiocarbonyl)disulfides was achieved by employing t-BuOK as a promoter. Based on this methodology, twenty nine novel indole-dithiocarbamate compounds were prepared in moderate to excellent yields at room temperature. All compounds were evaluated for their anti-inflammatory activity. Most of the compounds exhibited high potency on inhibiting the releasing of tumor necrosis factor alpha (TNF-α) and interleukin-6 (IL-6). Four of them were found to suppress in vitro cytokine production in a dose-dependent manner with IC50 values in the nanomolar range. Additionally, 3-methyl-1H-indol-1-yl dimethylcarbamodithioate (3o) effectively ameliorated histopathological changes of lung tissues and attenuated lipopolysaccharides (LPS)-induced acute lung injury (ALI) in vivo. These data suggest that the new indole-dithiocarbamate derivatives could be particularly useful for further pharmaceutical development for the treatment of ALI.

Correlation of Histopathological Changes with the Manner of Death in Fatal Burns in a Tertiary Care Hospital in Northern India

Objectives: To find the correlation of manner of death with histopathological changes in fatal burns in atertiary care hospital in north India.Method: This was a comparative study. Cases were thoroughly studied usingspecially designed proformathat included the demographic profile of deceased along with information gathered from relatives, police& hospital records and autopsy findings. Before taking the lung sample, proper consent was taken fromthe relatives after explaining the purpose of the study. After gross examination, sections were taken fromdifferent lobes of lungs.Results: Tracheal congestion was found mainly in accidental deaths (49.77%), followed by suicidal deathswith 28.57% and homicidal deaths with 21.66%. This difference was found to be statistically significant(p<0.001). Lung Consolidation was more commonly seen in accidental and suicidal deaths (48.4%) ascompared to homicidal deaths (3.19%). Various other variables were also correlated with type of burns.Conclusion: This association of histopathological changes in lung tissue could help to ascertain the modeof Death, as well as can hint towards conduction of proper inquest in suspicious cases of so called suicidaldeaths

IL-9 exacerbates the development of chronic obstructive pulmonary disease through oxidative stress.

To investigate the role of IL-9 in chronic obstructive pulmonary disease (COPD), and to explore its potential mechanism. A mouse COPD model was established by exposure to cigarette smoke. COPD mice were then randomly assigned into two groups, including: the PBS group and the IL-9 antibody group. The above two groups were treated with phosphate-buffered saline (PBS) or IL-9 injection, respectively. The histopathological changes in lung tissues of mice were observed by hematoxylin-eosin (H&E) staining. Immunohistochemistry was performed to detect IL-9-positive (IL-9+) cells in lung tissues. Expression levels of IL-9, sIL-9R, STAT3, and p-STAT3 in peripheral blood of mice were determined by quantitative Real time-polymerase chain reaction (qRT-PCR), enzyme-linked immunosorbent assay (ELISA), and Western blot, respectively. In addition, the expression levels of superoxide dismutase (SOD), malondialdehyde (MDA), and reactive oxygen species (ROS) were detected. H&E staining results showed that the airway wall structure of COPD mice in the PBS group was irregular. Ciliated columnar epithelium exhibited marked degeneration, necrosis and shedding. Besides, numerous inflammatory cell infiltration, narrowing and rupture of the alveolar septa, and larger cysts fused by adjacent alveoli were observed. H&E staining also indicated that the structure of alveolar epithelium was severely impaired in COPD mice. However, the pathological changes in lung tissues of mice in the IL-9 antibody group were much milder than those of the PBS group. Immunohistochemistry results showed a significant deposition of IL-9+ cells in the lung tissues of the PBS group. Meanwhile, the mRNA and protein levels of IL-9, sIL-9R, and p-STAT3 in the PBS group were also remarkably higher than those of the IL-9 antibody group. In addition, SOD content in the PBS group was significantly decreased, whereas the levels of MDA and ROS were significantly increased than those of the IL-9 antibody group. IL-9 activated STAT3 and aggravated lung injury in COPD mice by increasing inflammatory and oxidative stress.

Effects of calcitonin gene-related peptide on aquaporin 1 and aquaporin 5 expressions in young rats with acute lung injury

Objective To explore the effect of calcitonin gene-related peptide (CGRP) on expressions of aquaporin (AQP)1 and AQP 5 in young rats with acute lung injury(ALI) caused by lipopolysaccharide(LPS). Methods Eighty-four young rats were randomly divided into control group, ALI model group and CGRP group.The rats in ALI model group were given intraperitoneal injection of LPS (5 mg/kg)for 2, 6, 12, 24 hours; while the rats in CGRP group were given intraperitoneal CGRP (1 mg/kg) after 1 h injection of LPS.At 2 h, 6 h, 12 h and 24 h, all rats were sacrificed and lung tissues were obtained.The histopathological changes in lung tissues were evaluated by adopting hematoxylin-eosin staining, and wet/dry(W/D) was measured.The mRNA and protein levels of AQP1 and AQP5 in lung tissues were detected by adopting fluorogenic quantitative PCR(qPCR) and Western blot. Results Pathological stain showed that rats in control group had a normal lung tissue structure, and LPS made lung tissue edema, narrowing the alveolar cavity and inflammatory cell infiltration.CGRP attenuated the effect of LPS on rat′s lung.The W/D ratio of lung tissue was significantly higher than that in the control group, and CGRP reduced the W/D ratio of lung tissue.qPCR showed that the mRNA levels of AQP1 and AQP5 from rats in ALI group (0.009±0.001 and 0.055±0.006) decreased compared with those in the control group (0.035±0.002 and 0.167±0.006) and CGRP group (0.024±0.002 and 0.134±0.012) (all P<0.001). Western blot results showed after 24 h injection of LPS, both AQP1 and AQP5 levels from ALI group (0.397±0.041 and 0.215±0.029) were significantly lower than those in the control group (0.850±0.020 and 0.741±0.032) (all P<0.001), and their levels in CGRP group (0.593±0.065 and 0.461±0.039) were also lower than those in the control group, but higher than those in ALI group (all P<0.001). Conclusion CGRP can enhance AQP1 and AQP5 levels and reduce pulmonary edema, and it has a protective effect on rats with acute lung injury. Key words: Acute lung injury; Calcitonin gene-related peptide; Aquaporin

Vitamin E antagonizes ozone-induced asthma exacerbation in Balb/c mice through the Nrf2 pathway

Millions of people are regularly exposed to ozone, a gas known to contribute significantly to worsening the symptoms of patients with asthma. However, the mechanisms underlying these ozone exacerbation effects are not fully understood. In this study, we examined the exacerbation effect of ozone in OVA-induced asthma mice and tried to demonstrate the protective mechanism of vitamin E (VE). An asthma mouse model was established, and used to identify the exacerbating effects of ozone by assessing cytokine and serum immunoglobulin concentrations, airway leukocyte infiltration, histopathological changes in lung tissues, and airway hyper-responsiveness. We then determined the amount of reactive oxygen species (ROS) accumulated, the extent to which VE induced ROS elimination, and examined the antagonistic effects of VE on the ozone-induced exacerbating effects. This study showed that 1-ppm ozone exposure could exacerbate OVA-induced asthma in mice. More importantly we found that ozone induced oxidative stress in asthmatic airways may lead to the inhibition of Nuclear factor-erythroid 2-related factor 2 (Nrf2), and may subsequently induce even more exaggerated oxidative stress associated with asthma exacerbation. Through VE induced Nrf2 activation and the subsequent increase in Nrf2 target protein expression, this study suggests a novel mechanism for alleviating ozone exacerbated asthma symptoms.

Protective effects of GAS6 on acute lung injury in septic mice

Objective To explore the protective effect of GAS6 (growth arrest-specific gene 6 protein) on lung injury in septic mice so as to elucidate the mechanism. Methods Ninty male BALB/c mice were divided into 6 groups (n=15): sham operation group, CLP group, CLP+ vehicle group, CLP+ GAS6 group (1 μg), CLP+ GAS6 group (5 μg), CLP+ GAS6 group (10 μg). Mice in CLP groups and GAS6 groups were made to be sepsis models by CLP. GAS6 was administrated after CLP in GAS6 groups by intravenous injection. And mice in sham group were only treated with laparotomy without CLP. And 24 h later, all survived mice were sacrificed to obtain blood and lung tissue. Serum levels of TNF-α, IL-1β were measured by using ELISA. The lung wet/dry ratio was calculated. Histopathological changes of lung tissues were observed under light microscope. NF-κB and IκB-α were assayed by Western blotting. Data were analyzed by SPSS 23.0. Statistical analyses were performed using independent sample t-test to compare between two groups or one-way analysis of variance test to compare among multiple groups. Results The serum levels of TNF-α (P=0.000), IL-1β (P=0.000), the lung W/D (P=0.000), pulmonary pathological change (P=0.000), the levels of NF-κB(P=0.006) in CLP group were higher than those in sham group, while IκB-α (P=0.001) in CLP groups was lower than those in sham group. The GAS6 significantly reduced the serum levels of TNF-α (P=0.000), IL-1β (P=0.000), the lung W/D (P=0.000), pathogenesis of lung tissue (P=0.000) and the levels of NF-κB (P=0.000) in septic mice. The IκB-α (P=0.009)was increased after treatment with GAS6 in a dose-dependent manner. Conclusions GAS6 has protective effect on septic lung injury in mice, and its molecular mechanism may be associated with inhibiting inflammatory response and suppressing NF-κB nuclear translocation. Key words: Gas6; Sepsis; Mice; Acute lung injury; Inflammatory factors; TNF-α; IL-1β; NF-κB; IκB-α

Dietary unsaponifiable fraction of extra virgin olive oil supplementation attenuates lung injury and DNA damage of rats co-exposed to aluminum and acrylamide.

Aluminum chloride (AlCl3) and acrylamide (ACR) are well known as environmental pollutants inducing oxidative stress. Our study investigated the effects of these contaminants and if the hydrophilic fraction of extra virgin olive oil was able to prevent lung oxidative stress and DNA damage. Animals were divided into four groups of six each: group 1, serving as controls, received distilled water; group 2 received in drinking water aluminum chloride (50mg/ kg body weight) and by gavage acrylamide (20mg/kg body weight); group 3 received both aluminum and acrylamide in the same way and the same dose as group 2 and hydrophilic fraction from olive oil (OOHF) (1ml) by gavage; group 4 received only OOHF by gavage. Exposure of rats to both aluminum and acrylamide provoked oxidative stress in lung tissue based on biochemical parameters and histopathological alterations. In fact, we have observed an increase in malondialdehyde (MDA), H2O2, and advanced oxidation protein product (AOPP) and a decrease in reduced glutathione (GSH), non-protein thiols (NPSH), and vitamin C levels. Activities of catalase (CAT), glutathione peroxidase (GPx), and superoxide dismutase (SOD) were also decreased. Histopathological changes in lung tissue were noted like emphysema, vascular congestion, and infiltration of inflammatory cells. A random DNA degradation was observed on agarose gel in the lung of AlCl3 and acrylamide (ACR)-treated rats. Co-administration of OOHF to treated rats improved biochemical parameters to near control values and lung histoarchitecture. The smear formation of genomic DNA was reduced. The hydrophilic fraction of extra virgin olive oil might provide a basis for developing a new dietary supplementation strategy in order to prevent lung tissue damage.

Protective effects of phillyrin against influenza A virus in vivo.

Influenza A virus infection represents a great threat to public health. However, owing to side effects and the emergence of resistant virus strains, the use of currently available anti-influenza drugs may be limited. In order to identify novel anti-influenza drugs, we investigated the antiviral effects of phillyrin against influenza A virus infection in vivo. The mean survival time, lung index, viral titers, influenza hemagglutinin (HA) protein and serum cytokines levels, and histopathological changes in lung tissue were examined. Administration of phillyrin at a dose of 20mg/kg/day for 3days significantly prolonged the mean survival time, reduced the lung index, decreased the virus titers and interleukin-6 levels, reduced the expression of HA, and attenuated lung tissue damage in mice infected with influenza A virus. Taken together, these data showed that phillyrin had potential protective effects against infection caused by influenza A virus.

Flavonoids from Radix Tetrastigmae improve LPS-induced acute lung injury via the TLR4/MD-2-mediated pathway.

Total flavonoids isolated from Radix Tetrastigmae (RTFs) possess immunomodulatory activity, particularly on inflammation. In mice with lipopolysaccharide (LPS)‑induced acute lung injury (ALI), treatment with RTFs at 40, 80 and 160mg/kg significantly reduced leukocyte infiltration, improved histopathological changes in lung tissues and decreased the LPS‑induced production of several inflammatory mediators in the bronchoalveolar lavage fluid (BALF), which included the chemotatic factors, granulocyte colony‑stimulating factor, monocyte inflammatory protein‑1α and B‑lymphocyte colony inflammatory cytokines, including interleukin (IL)‑1β, IL‑6, IL‑12p40 and tumor necrosis factor‑α, in a dose‑dependent manner. In addition, the expression of the Toll‑like receptor4 (TLR4)/myeloid differentiation factor‑2 (MD‑2) compound, the phosphorylation of p38 mitogen‑activated protein kinase (p38MAPK), c‑Jun N‑terminal kinase (JNK) and nuclear transcription factor‑κB (NF‑κB), in addition to the DNA binding activity of NF‑κB p65 in lung tissues, were all attenuated following RTF treatment. However, RTF treatment had no effect on extracellular signal‑regulated kinase (ERK). In conclusion, RTFs contributed to the regulation of LPS‑induced ALI through the TLR4/MD-2-mediated NF‑κB, JNK and p38MAPK pathways. This may be a potential therapeutic option for the treatment of inflammatory diseases.