Lung TNF-α Research Articles

The Potency of Camellia Sinensis L. to Reduce Proinflammatory Cytokine Levels in the Acute Respiratory Distress Syndrome Rat Model

This study was conducted in order to ascertain how green tea extract (GTE) could affect inflammatory markers, including level of interleukin-(IL)-12, IL-18 of serum and lung, tumor necrosis factor (TNF)-α, gene expression of NLR family-pyrin-domain containing 3 (NLRP3) of lung, nuclear factor kappa B (NF-κB), lung histopathology, and IL-6 expression of lung tissue in lipopolysaccharide (LPS)-treated rats as ARDS animal model. Rats were given GTE at dosages of 0, 50, 400, 800 mg/kg of body weight for 28 days to boost their immune systems. The rats were then stimulated with LPS (5 g/kg of BW) and after that continued to receive GTE for 28 days. Levels of serum or lung IL-18, IL-12, TNF-α, were measured using the ELISA method; expression of lung NF-κB and NLRP3 was measured by qRT-PCR; immunohistochemistry (IHC) was implemented to assess lung IL-6 expression; and lung histopathology was evaluated through the bleeding, inflammation, and alveolus scores. GTE had the ability to lower serum IL-18, lung TNF-α, and lung IL-12 levels; suppress the lung gene expression of NF-κB, NLRP-3, IL-6 expression; and improve lung histopathology. Green tea extract inhibited inflammation in the ARDS rat model by decreasing the proinflammatory cytokine level and proinflammatory gene expression.

Anti-Allergic Inflammatory Effect of Agarum cribrosum and Its Phlorotannin Component, Trifuhalol A, against the Ovalbumin-Induced Allergic Asthma Model.

Asthma is a chronic inflammatory disease involving structural changes to the respiratory system and severe immune responses mediated by allergic cytokines and pro-inflammatory mediators. Agarum cribrosum (AC) is a kind of seaweed which contains a phlorotannin, trifuhalol A. To evaluate its anti-allergic inflammatory effect against asthma, an ovalbumin inhalation-induced mouse asthma model was used. Histologic observations proved that trifuhalol A is minimizing the lung and tracheal structure changes as well as the infiltration of eosinophils and mast cells against ovalbumin inhalation challenge. From the serum and bronchoalveolar lavage fluid, ovalbumin-specific IgE and Th2-specific cytokines, IL-4, -5, and -13, were reduced with trifuhalol A treatment. In addition, IL-1β, IL-6, and TNF-α concentrations in lung homogenate were also significantly reduced via trifuhalol A treatment. Taken together, trifuhalol A, isolated from AC, was able to protect lung and airways from Th2-specific cytokine release, and IgE mediated allergic inflammation as well as the attenuation of IL-1β, IL-6, and TNF-α in lung, which results in the suppression of eosinophils and the mast cells involved asthmatic pathology.

Fine Particulate Matter Perturbs the Pulmonary Microbiota in Broiler Chickens.

(1) Fine particulate matter (PM2.5) seriously affects the respiratory tract health of both animals and humans. Growing evidence indicates that the pulmonary microbiota is involved in the development of respiratory tract health; however, there is still much that is unknown about the specific changes of pulmonary microbiota caused by PM2.5 in broilers. (2) In this experiment, a total of 48 broilers were randomly divided into a control group and PM-exposure group. The experiment lasted for 21 days. Microbiota, inflammation biomarkers, and histological markers in the lungs were determined. (3) On the last day of the experiment, PM significantly disrupted the structure of lung tissue and induced chronic pulmonary inflammation by increasing IL-6, TNFα, and IFNγ expression and decreasing IL-10 expression. PM exposure significantly altered the α and β diversity of pulmonary microbiota. At the phylum level, PM exposure significantly decreased the Firmicutes abundance and increased the abundance of Actinobacteria and Proteobacteria. At the genus level, PM exposure significantly increased the abundance of Rhodococcus, Achromobacter, Pseudomonas, and Ochrobactrum. We also observed positive associations of the above altered genera with lung TNFα and IFNγ expression. (4) The results suggest that PM perturbs the pulmonary microbiota and induces chronic inflammation, and the pulmonary microbiota possibly contributes to the development of lung inflammation.

Soybean Seeds (Glycine max L.) Extract Against Cytokine Storm in ARDS Rat Model through Inhibiting Inflammation Marker

Several studies have suggested that "cytokine storms" are significant causes of the severity of COVID-19. Controlling and inhibiting the cytokine storm in COVID-19 could prevent the spread of COVID-19 and saves patient lives. Soybean (Glycine max L.) is known to have various biological activities. This study aims to examine bioactive compounds in SSE and the effect of SSE on the ARDS rats model. A total of 25 Sprague Dawley Lipopolysaccharide-induced rats were used. Determination of serum IL-1β, IL-12, and lung TNF-α levels was performed by ELISA method. NF-κB and IFN-γ expression were determined by the qRTPCR method. IL-6 expressions were analyzed by immunohistochemistry assay. The bleeding, inflammation, and alveolus collapse score were analyzed using the HE staining method. The results showed that SSE could decrease the level of IL-1β, IL-12, TNF-α, IL-6, NF-kB, and IFN-γ and improve the bleeding, inflammation, and alveolus score in the lung. SSE could decrease the pro-inflammatory cytokines and improve lung condition in ARDS rats model.

A Supraceliac Aortic Cross Clamping Model to Explore Remote Lung Injury and the Endothelial Glycocalyx

We hypothesized that supraceliac aortic cross clamping could induce lung injury mediated by an inflammatory ischemia-reperfusion (IR) trigger. We aimed to characterize glycocalyx (GCX), a component of endothelial membrane, participating to remote lung injury. Rats underwent supraceliac aortic cross clamping for 40min and were sacrificed at 0, 3, 6, and 24hr of reperfusion (n=10/group). Each group was compared to sham (n=6/group). GCX products (syndecan-1 [Sdc-1] and heparan sulfate [HS]), tumor necrosis factor-alpha (TNF-α), and interleukin-1β (IL-1β) were measured in plasma (enzyme-linked immunosorbent assay[ELISA]). Lungs were harvested for measurements of TNF-α, IL-1β (polymerase chain reaction) and Sdc-1 (western blotting [WB]). Histologic lung injury scoring and pulmonary gravimetry were analyzed in a blinded manner. Plasmatic Sdc-1, HS, TNF-α, and IL-1β reached peak levels at 3hr. Levels were significantly higher in clamping groups than sham at 6hr for Sdc-1, at 0 and 3hr for HS, at 3 and 6hr for TNF-α, and at 3hr for IL-1β. Lung TNF-α and Interleukin-1β reached peak levels at 6hr. Levels were significantly higher than sham at 6 and 24hr for TNF-α and at 6hr for IL-1β. Lung Sdc-1 was lowest at 3hr. Sdc-1 was not significantly different compared to sham at the different reperfusion times. At 3hr, it was 0.27±0.03 vs. 0.33±0.02 (sham) (P=0.09). Histopathologic scores at 6 and 24hr were higher in clamping groups than sham. At 6 and 24hr, it was higher for hemorrhage, polynuclear neutrophil (PNN) infiltration and intravascular leukocytes. Pulmonary edema was higher by gravimetry at 0 and 6hr. Supra celiac aortic clamping causes early lung injury in relation with a systemic inflammatory response associated with altered GCX structure.

The combination of chronic stress and smoke exacerbated depression-like changes and lung cancer factor expression in A/J mice: Involve inflammation and BDNF dysfunction.

Depression is positively correlated with the high incidence and low survival rate of cancers, while more cancer patients suffer depression. However, the interaction between depression and cancer, and possible underline mechanisms are unclear. Chronic unpredictable mild stress (CUMS) was used to induce depression, and smoke to induce lung cancer in lung cancer vulnerable AJ mice. After 8 weeks, sucrose preference and forced swimming behaviors were tested. Blood corticosterone concentration, and levels of cytokines, lung cancer-related factors, brain-derived neurotrophic factor (BDNF) and apoptosis-related factors in the lung, amygdala and hippocampus were measured. Compared to control group, CUMS or smoke decreased sucrose consumption and increased immobility time, which were deteriorated by stress+smoke. CUMS, smoke or both combination decreased mononuclear viability and lung TNF-α concentration, increased serum corticosterone and lung interleukin (IL)-1, IL-2, IL-6, IL-8, IL-10, IL-12 and HSP-90α concentrations. Furthermore, stress+smoke caused more increase in corticosterone and IL-10, but decreased TNF-α. In parallel, in the lung, Bcl-2/Bax and lung cancer-related factors CDK1, CDC20, P38α etc were significantly increased in stress+smoke group. Moreover, CUMS decreased BDNF, while CUMS or smoke increased TrkB and P75 concentrations, which were exacerbated by stress+smoke. In the amygdala, except for CUMS largely increased Bax/Bcl-2 and decreased TrkB, each single factor decreased BDNF and IL-10, but increased P75, IL-1β, IL-12, TNF-α concentrations. Changes in Bax/Bcl-2, IL-10 and TNF-α were further aggravated by the combination. In the hippocampus, except for CUMS largely increased P75 concentration, each single factor significantly increased Bax/Bcl-2 ratio, IL-1β and TNF-α, but decreased BDNF, TrkB and IL-10 concentrations. Changes in Bax, Bax/Bcl-2, IL-10 and TNF-α were further aggravated by the combination. These results suggest that a synergy between CUMS and smoke exposure could promote the development of depression and lung cancer, through CUMS increased the risk of cancer occurrence, and conversely lung cancer inducer smoke exposure deteriorated depressive symptoms.

Live mucosal vaccination stimulates potent protection via varied CD4+ and CD8+ T cell subsets against wild-type Brucella melitensis 16M challenge.

Re-emerging zoonotic pathogen Brucella spp. continues to impact developing countries and persists in expanding populations of wildlife species in the US, constantly threatening infection of our domestic herds. The development of improved animal and human vaccines remains a priority. In this study, immunity to a novel live attenuated B. melitensis strain, termed znBM-mC, was characterized. An oral prime, intranasal (IN) boost strategy conferred exquisite protection against pulmonary challenge, with wild-type (wt) B. melitensis providing nearly complete protection in the lungs and spleens from brucellae colonization. Vaccination with znBM-mC showed an IFN-γ+ CD8+ T-cell bias in the lungs as opposed to Rev 1-vaccinated mice showing IFN-γ+ CD4+ T-cell inclination. Lung CD4+ and CD8+ effector memory T cells (TEMs) increased over 200-fold; and lung CD4+ and CD8+ resident memory T cells (TRMs) increased more than 250- and 150-fold, respectively. These T cells served as the primary producers of IFN-γ in the lungs, which was essential for vaccine clearance and the predominant cytokine generated pre-and post-challenge with wt B. melitensis 16M; znBM-mC growth could not be arrested in IFN-γ−/− mice. Increases in lung TNF-α and IL-17 were also induced, with IL-17 being mostly derived from CD4+ T cells. Vaccination of CD4−/−, CD8−/−, and B6 mice with znBM-mC conferred full protection in the lungs and spleens post-pulmonary challenge with virulent B. melitensis; vaccination of IL-17−/− mice resulted in the protection of the lungs, but not the spleen. These data demonstrate the efficacy of mucosal vaccine administration for the generation of protective memory T cells against wt B. melitensis.

Jacareubin inhibits TLR4-induced lung inflammatory response caused by the RBD domain of SARS-CoV-2 Spike protein.

BackgroundCOVID-19, the disease caused by SARS-CoV-2 virus infection, has been a major public health problem worldwide in the last 2 years. SARS-CoV-2-dependent activation of innate immune receptors contributes to the strong local and systemic inflammatory reaction associated with rapid disease evolution. The receptor-binding domain (RBD) of Spike (S) viral protein (S-RBD) is essential for virus infection and its interacting molecules in target cells are still under identification. On the other hand, the search for accessible natural molecules with potential therapeutic use has been intense and remains an active field of investigation.MethodsC57BL6/J (control) and Toll-like receptor (TLR) 4-deficient (Lps del) mice were nebulized with recombinant S-RBD. Tumor Necrosis Factor-alpha (TNF-α) and Interleukin (IL)-6 production in bronchoalveolar lavages (BALs) was determined by enzyme-linked immunosorbent assay (ELISA). Lung-infiltrating cells recovered in BALs were quantified by hematoxylin–eosin (H&E) stain. In selected groups of animals, the natural compound Jacareubin or dexamethasone were intraperitoneally (ip) administered 2 hours before nebulization.ResultsA rapid lung production of TNF-α and IL-6 and cell infiltration was induced by S-RBD nebulization in control but not in Lps del mice. Pre-treatment with Jacareubin or dexamethasone prevented S-RBD-induced TNF-α and IL-6 secretion in BALs from control animals.ConclusionsS-RBD domain promotes lung TNF-α and IL-6 production in a TLR4-dependent fashion in C57BL6/J mice. Xanthone Jacareubin possesses potential anti-COVID-19 properties that, together with the previously tested anti-inflammatory activity, safety, and tolerance, make it a valuable drug to be further investigated for the treatment of cytokine production caused by SARS-CoV-2 infection.Supplementary InformationThe online version contains supplementary material available at 10.1007/s43440-022-00398-5.

Extracellular Vesicles From Paracoccidioides brasiliensis Can Induce the Expression of Fungal Virulence Traits In Vitro and Enhance Infection in Mice.

Extracellular vesicles (EVs) are cellular components involved in cargo delivery to the extracellular environment, including the fungal cell wall. Their importance in cell–cell communication, cell wall remodeling, and fungal virulence is starting to be better explored. In the human pathogenic Paracoccidioides spp., our group has pioneered the description of the EV secretome, carbohydrate cargo, surface oligosaccharide ligands, lipid, and RNA content. Presently, we studied the role of fungal EVs in the context of the virulent/attenuated model of the P. brasiliensis Pb18 isolate, which consists of variants transiently displaying higher (vPb18) or attenuated (aPb18) virulence capacity. In this model, the virulence traits can be recovered through passages of aPb18 in mice. Here, we have been able to revert the aPb18 sensitivity to growth under oxidative and nitrosative stress upon previous co-incubation with vEVs from virulent vPb18. That was probably due to the expression of antioxidant molecules, considering that we observed increased gene expression of the alternative oxidase AOX and peroxiredoxins HYR1 and PRX1, in addition to higher catalase activity. We showed that aEVs from aPb18 stimulated macrophages of the RAW 264.7 and bone marrow-derived types to express high levels of inflammatory mediators, specifically, TNF-α, IL-6, MCP-1, and NO. In our experimental conditions, subcutaneous treatment with EVs (three doses, 7-day intervals) before vPb18 challenge exacerbated murine PCM, as concluded by higher colony-forming units in the lungs after 30 days of infection and histopathology analysis. That effect was largely pronounced after treatment with aEVs, probably because the lung TNF-α, IFN-γ, IL-6, and MCP-1 concentrations were specially increased in aEV-treated when compared with vEV-treated mice. Our present studies were performed with EVs isolated from yeast cell washes of confluent cultures in Ham’s F-12 defined medium. Under these conditions, vEVs and aEVs have similar sizes but probably distinct cargo, considering that vEVs tended to aggregate upon storage at 4°C and −20°C. Additionally, aEVs have decreased amounts of carbohydrate and protein. Our work brings important contribution to the understanding of the role of fungal EVs in cell–cell communication and on the effect of EVs in fungal infection, which clearly depends on the experimental conditions because EVs are complex and dynamic structures.

BN82002 alleviated tissue damage of septic mice by reducing inflammatory response through inhibiting AKT2/NF-κB signaling pathway

BN82002 is well-known as an inhibitor of the CDC25 phosphatase. However, it was recently reported that BN82002 also selectively suppressed AKT2 and reduced inflammatory responses in lipopolysaccharide (LPS)-stimulated macrophage-like RAW264.7 cells. Therefore, in this study, we evaluated the alleviating efficacy of BN82002 in sepsis in vivo. BN82002 (50 μM) suppressed the mRNA levels of cyclooxygenase (COX)-2, inducible nitric oxide synthase (iNOS), tumor necrosis factor (TNF)-α, interleukin (IL)-1β, and IL-6 in LPS-treated peritoneal macrophages without cytotoxicity. The septic in vivo mouse model was established on the basis of the endotoxin model using poly(I:C) (10 mg/kg) and LPS (54 mg/kg). In histological analysis, peritoneal injection of BN82002 (20 mg/kg) significantly reduced lung, kidney, and liver damage. Lung edema and serum alanine transaminase (ALT), aspartate transaminase (AST), TNF-α, IL-1β, and nitric oxide (NO) levels also were decreased by BN82002 (20 mg/kg). In addition, BN82002 (20 mg/kg) suppressed the mRNA levels of TNF-α in lung and liver tissues. Gene expression levels of IL-1β and IL-6 were decreased in lung, kidney, and liver in the BN82002 (20 mg/kg) group. Furthermore, p-AKT2 and p-IκBα levels were reduced by BN82002 (20 mg/kg). Finally, all septic mice died 7 days after poly(I:C)/LPS-injection, whereas 4 mice in the BN82002 (20 mg/kg) group, survived strongly suggesting that BN82002 reduces sepsis mortality. In conclusion, we verified that pre-treatment with BN82002 protects against tissue damage and increases survival by inhibiting AKT2-NF-κB signaling in septic mice. These results suggest that BN82002 could be utilized in the treatment of sepsis.

Pro-inflammatory cytokines/chemokines, TNF-α, IL-6 and MCP-1, as biomarkers for the nephro- and pneumoprotective effect of silibinin after hepatic ischemia/reperfusion: Confirmation by immunohistochemistry and qRT-PCR.

The present study investigated the potential nephro- and pneumoprotective effect of silibinin (Si) after hepatic ischemia-reperfusion (I/R) injury, by measuring pro-inflammatory factors. Sixty-three rats were randomly assigned into three groups, as follows: (a) the sham group (n = 7 rats), subjected to opening and closing the abdomen; (b) the control group (n = 28 rats), subjected to 45-min hepatic ischemia followed by reperfusion; and (c) the silibinin group (n = 28), subjected to 45-min hepatic ischemia followed by intravenous administration of lyophilised SLB-HP-β-CD before reperfusion. Control and silibinin groups were further subdivided into time-point groups, according to the duration of reperfusion. TNF-α, IL-6 and MCP-1 expressions were determined immunohistochemically and by qrT-PCR at each time-point. Kidney TNF-α expression was significantly lower at 180 and 240 min, while lung TNF-α expression was significantly lower at 240 min. Comparison between the control and Si group at the same time-points showed very strong evidence of difference at 240 min, with the levels of IL-6 shifting towards lower values in the Si group. Finally, we found a high MCP-1 expression after 120 min. We conclude that hepatic I/R injury remotely increases pro-inflammatory mediators in the kidney and lung, whereas silibinin shows a time-dependent nephro- and pneumoprotective effect.

Aerobic Exercise Improves Pulmonary Fibrosis by Improving Insulin Resistance and Inflammation in Obese Mice.

BackgroundPrevious studies have demonstrated that obesity is associated with pulmonary fibrosis. We attempted to identify whether regular aerobic exercise (AE) can protect against high-fat diet (HFD)-associated pulmonary fibrosis.MethodsForty-eight C57BL/6 mice were randomly assigned to four groups: chow group (Ch), chow plus exercise group (CE), obesity group (Ob), and obesity plus exercise group (OE). The mice were fed either an HFD or a chow diet for 16 weeks, and low-intensity aerobic exercise (AE) was performed in the last 8 weeks. We measured the degree of pulmonary fibrosis; pulmonary inflammation; oxidative stress parameters; insulin resistance-related indicators; the number of inflammatory cells in bronchoalveolar lavage fluid (BALF); the mRNA expression levels of IL-10, IL-1β, TGF-β, TNF-α, CXCL-1, IL-17, MMP-9, MPO, NE, and sirt-1; and the BALF levels of CXCL-1, IL-17, TGF-β, IL-10, IL-1β, and TNF-α in lung tissue.ResultsAE in obese mice protected against obesity-associated pulmonary fibrosis, chronic inflammation, pro-oxidative/antioxidative imbalance, and insulin resistance. AE ameliorated the HFD-induced inflammatory response and neutrophil infiltration in the lung. AE downregulated BALF levels of CXCL-1, IL-1β, TNF-α IL-17, and TGF-β but upregulated BALF levels of IL-10. AE decreased IL-1β, TGF-β, TNF-α, CXCL-1, IL-17, MMP-9, MPO, and NE mRNA expression levels but upregulated IL-10 and sirt-1 mRNA expression levels in the lung.ConclusionsAE protects against HFD-induced pulmonary fibrosis by improving obesity-associated insulin resistance, chronic low-grade inflammation, and pro-oxidative/antioxidative imbalance. AE improved HFD-induced pulmonary fibrosis by suppressing IL-17, TGF-β, NE, and MMP-9 expression and activating IL-10 and sirt-1 expression.

Dietary New Zealand propolis supplementation reduced proinflammatory cytokines in an acute mouse model of air pollution exposure, without impacting on immune cell infiltration or lung function

• Propolis reduced urban dust-induced lung TNFα, IL-4, and IL-6 production in mice. • Propolis did not alter urban dust-induced immune cell infiltration into mice lungs. • Propolis did not alter urban dust-induced airways constriction in mice. • This suggests that Propolis only partially reduces inflammatory responses in an urban dust mouse model. Air pollution is estimated to cause 7 million annual deaths globally. Our aim was to determine if dietary propolis consumption could prevent the immune and functional damage in a mouse model of acute urban dust exposure. Female C57BL/6J mice were challenged three times with intranasal urban dust over seven days which significantly increased proinflammatory cytokines and immune cells in the lung 24 h post final challenge. Dietary New Zealand propolis (2%) with gamma cyclodextrin supplementation reduced urban dust-induced lung TNFα, IL-4, and IL-6 cytokine production; but did not alter immune cell infiltration into the lung, or lung function outcomes. This suggests that daily consumption of 8% propolis with gamma cyclodextrin supplemented food was sufficient to reduce urban dust pollution-induced proinflammatory cytokine production but was not sufficient to prevent immune cell recruitment into the lung or lung function decline in a murine model of lung inflammation.

An aqueous pomegranate peel extract (Punica granatum) protect against Elastase-induced pulmonary emphysema in Sprague Dawley rats model

We investigated the effect of Punica granatum peel aqueous extract (PGE), on pulmonary inflammation and alveolar degradation induced by intratracheal administration of Elastase in Sprague Dawley rats. Lung inflammation was induced in rats by intratracheal instillation of Elastase. On day 1 and 2, animals received an intraperitoneal injection of PGE (200 mg/mL), three hours later, they were intratracheally instilled with 25U/kg pancreatic porcine Elastase. Animals were sacrificed 7 days later. Bronchoalveolar lavage (BAL) were collected and cellularity, histology and mRNA expression of Monocyte chemotactic protein 1(MCP-1), Tumor Necrosis Factor-Alpha (TNF-α), Interleukin 6 (IL-6), and Matrix Metalloproteinase-2 (MMP-2) were studied. In addition, activity of TNF- α, IL-6 and MCP-1 on BAL were also analyzed by ELISA Kit. Elastase administration increased: BAL cellularity, neutrophils recruitment and BAL MCP1, IL-6 expressions. It also increased lung TNF-α, MCP-1, MMP-2 expressions, platelets recruitment, histological parameters at 7th day of elastase treatment. Intraperitoneal injection of 200 mg/kg of PGE reduced, significantly, BAL cellularity, and neutrophils recruitment. However, in animal treated with PGE, MCP-1, MMP-2 and IL-6 on day 7, were similar to the Sham group. Treatment with PGE (200 mg/ kg) also significantly reduced lung TNF-α, and MCP-1 expression. This study reveals that PGE Punica granatum protects against elastase lung inflammation and alveolar degradation induced in rats.

Vendor effects on murine gut microbiota and its influence on lipopolysaccharide-induced lung inflammation and Gram-negative pneumonia

BackgroundThe microbiome has emerged as an important player in the pathophysiology of a whole spectrum of diseases that affect the critically ill. We hypothesized that differences in microbiota composition across vendors can influence murine models of pulmonary lipopolysaccharide (LPS) inflammation and Gram-negative pneumonia.MethodsA multi-vendor approach was used with genetically similar mice derived from three different vendors (Janvier, Envigo, Charles River). This model was employed to study the effect on the host response to a pulmonary LPS challenge (1 μg Klebsiella pneumoniae LPS, intranasal), as well as experimental K. pneumoniae infection (ATCC43816, 1 × 104 CFU, intranasal).ResultsGut microbiota analysis revealed profound intervendor differences in bacterial composition as shown by beta diversity and at various taxonomic levels. Tumor necrosis factor (TNF)-α and interleukin (IL)-6 release in lung and bronchoalveolar lavage fluid (BALF) were determined 6 and 24 h after intranasal treatment with LPS. No differences were found between the groups, with the exception for Envigo, showing a higher level of TNFα in lung and BALF at 6 h compared to Janvier and Charles River. In another set of experiments, mice from different vendors were subjected to a clinically relevant model of Gram-negative pneumonia (K. pneumoniae). At 12 and 36 h post-infection, no intervendor differences were found in bacterial dissemination, or TNFα and IL-6 levels in the lungs. In line, markers for organ failure did not differ between groups.ConclusionsAlthough there was a marked variation in the gut microbiota composition of mice from different vendors, the hypothesized impact on our models of pulmonary inflammation and severe pneumonia was limited. This is of significance for experimental settings, showing that differences in gut microbiota do not have to lead to differences in outcome.

Curcumin analogs (B2BrBC and C66) supplementation attenuates airway hyperreactivity and promote airway relaxation in neonatal rats exposed to hyperoxia.

BackgroundThis study was undertaken to test the hypothesis that the newly synthesized curcuminoids B2BrBC and C66 supplementation will overcome hyperoxia‐induced tracheal hyperreactivity and impairment of relaxation of tracheal smooth muscle (TSM).Materials and methodsRat pups (P5) were exposed to hyperoxia (>95% O2) or normoxia for 7 days. At P12, tracheal cylinders were used to study in vitro contractile responses induced by methacholine (10−8–10−4M) or relaxation induced by electrical field stimulation (5–60 V) in the presence/absence of B2BrBC or C66, or to study the direct relaxant effects elicited by both analogs.ResultsHyperoxia significantly increased contraction and decreased relaxation of TSM compared to normoxia controls. Presence of B2BrBC or C66 normalized both contractile and relaxant responses altered by hyperoxia. Both, curcuminoids directly induced dose‐dependent relaxation of preconstricted TSM. Supplementation of hyperoxic animals with B2BrBC or C66, significantly increased catalase activity. Lung TNF‐α was significantly increased in hyperoxia‐exposed animals. Both curcumin analogs attenuated increases in TNF‐α in hyperoxic animals.ConclusionWe show that B2BrBC and C66 provide protection against adverse contractility and relaxant effect of hyperoxia on TSM, and whole lung inflammation. Both analogs induced direct relaxation of TSM. Through restoration of catalase activity in hyperoxia, we speculate that analogs are protective against hyperoxia‐induced tracheal hyperreactivity by augmenting H2O2 catabolism. Neonatal hyperoxia induces increased tracheal contractility, attenuates tracheal relaxation, diminishes lung antioxidant capacity, and increases lung inflammation, while monocarbonyl CUR analogs were protective of these adverse effects of hyperoxia. Analogs may be promising new therapies for neonatal hyperoxic airway and lung disease.

Pretreatment with dexmedetomidine alleviates lung injury in a rat model of intestinal ischemia reperfusion

The aim of the present study was to investigate the antioxidant mechanisms of dexmedetomidine against lung injury during intestinal ischemia reperfusion (IIR) in rats. The model of IIR-induced acute lung injury was established by occluding the superior mesenteric artery (SMA) for 1 h and reperfusing for 2 h using Sprague-Dawley rats. Pathological examination was used to assess the extent of the lung injury. Oxidative stress was evaluated by measuring malondialdehyde, myeloperoxidase and superoxide dismutase in the lung and plasma. The proinflammatory cytokines tumor necrosis factor-α and interleukin-6 were determined via an enzyme-linked immunosorbent assay. The mRNA and protein expression of nuclear factor-erythroid 2 related factor 2 (Nrf2) and heme oxygenase 1 (HO-1) were determined using a reverse transcription-quantitative polymerase chain reaction and western blotting. Pretreatment with dexmedetomidine significantly inhibited the oxidative stress response and proinflammatory factor release caused by IIR compared with the normal saline group (MDA and SOD in lung and plasma, P<0.05; MPO, IL-1β and TNF-α in lung and plasma, P<0.05). Dexmedetomidine improved pulmonary pathological changes in IIR rats compared with the normal saline group. Investigations into the molecular mechanism revealed that dexmedetomidine increased the expression levels of Nrf2 and HO-1 via activating α2 adrenergic receptors compared with the normal saline group. The antagonism of α2 adrenergic receptors may reverse the protective effect of dexmedetomidine on lung injury during IIR, including decreasing the expression levels of Nrf2 and HO-1, elevating the oxidative stress response and increasing the proinflammatory factor release. In conclusion, pretreatment with dexmedetomidine demonstrated protective effects against lung injury during IIR via α2 adrenergic receptors. The Nrf2/HO-1 signaling pathway may serve a function in the protective effect of dexmedetomidine.

The protective effects of vitamin E on lung injury caused by high temperature and PM2.5 in COPD rats

To investigate the effects of vitamin E on the respiratory function impairment in rats with chronic obstructive pulmonary disease (COPD) after exposed to high temperature and PM2.5. Fifty-four 7-week-old SPF male Wistar rats were randomly divided into 9 experimental groups (n=6). The rat COPD model was established by lipopolysaccharide (LPS) and smoke exposure. After modeled, the rats were tracheal instilled with PM2.5 (0 mg/ml, 3.2 mg/ml) and intraperitoneally injected with vitamin E at the dose of 40 mg/kg (20 mg/ml). Part of rats (high temperature groups) were then exposed to high temperature (40℃), once (8 h) a day for three consecutive days. After the last exposure, the lung function of rats was detected. The expression levels of inducible nitric oxide synthase (iNOS), tumor necrosis factor-α (TNF-α) and monocyte chemotactic protein-1 (MCP-1) were detected by corresponding ELISA kits. Compared with the control group, exposure of high temperature and PM2.5 could inhibit the lung function of COPD rats significantly (P＜0.05); the level of MCP-1 was increased significantly in PM2.5-exposure groups (P＜0.05); iNOS was increased significantly in the groups of high temperature (P＜0.05). Compared with the single-PM2.5 exposure groups, TNF-α in lung was decreased in the normal temperature health group and high temperature COPD group (P＜0.05) after treated with vitamin E; MCP-1 was decreased in all vitamin E-treated groups (P＜0.05); the decreased iNOS only appeared in the group of high temperature with vitamin E treatment. High temperature and PM2.5 could aggravate the inflammation of COPD rats. As an antioxidant, vitamin E may protect the lung from the damage effects.

AMPK activation attenuates inflammatory response to reduce ambient PM2.5-induced metabolic disorders in healthy and diabetic mice

Epidemiological and experimental studies have indicated that ambient fine particulate matter (PM2.5) exposure is associated with the occurrence and development of metabolic disorders such as obesity and type 2 diabetes mellitus (T2DM). However, the mechanism is not clear yet, and there are few studies to explore the possible prevention measure. In this study, C57BL/6 and db/db mice were exposed to concentrated PM2.5 or filtered air using Shanghai Meteorological and Environmental Animal Exposure System (Shanghai-METAS) for 12 weeks. From week 11, some of the mice were assigned to receive a subcutaneous injection of AMPK activator (AICAR). Lipid metabolism, glucose tolerance, insulin sensitivity and energy homeostasis were measured. Meanwhile, the respiratory, systemic and visceral fat inflammatory response was detected. The results showed that PM2.5 exposure induced the impairments of glucose tolerance, insulin resistance, lipid metabolism disorders and disturbances of energy metabolism in both C57BL/6 and db/db mice. These impairments might be consistent with the increased respiratory, circulating and visceral adipose tissue (VAT) inflammatory response, which was characterized by the release of IL-6 and TNF-α in lung, serum and VAT. More importantly, AICAR administration led to the significant enhancement of energy metabolism, elevation of AMPK as well as the decreased IL-6 and TNF-α in VAT of PM2.5-exposed mice, which suggesting that AMPK activation might attenuate the inflammatory responses in VAT via the inhibition of MAPKs and NFκB. The study indicated that exposure to ambient PM2.5 under the concentration which is often seen in some developing countries could induce the occurrence of metabolic disorders in normal healthy mice and exacerbate metabolic disorders in diabetic mice. The adverse impacts of PM2.5 on insulin sensitivity, energy homeostasis, lipid metabolism and inflammatory response were associated with AMPK inhibition. AMPK activation might inhibit PM2.5-induced metabolic disorders via inhibition of inflammatory cytokines release. These findings suggested that AMPK activation is a potential therapy to prevent some of the metabolic disorders attributable to air pollution exposure.

Caspase-(8/3) activation and organ inflammation in a rat model of resuscitated hemorrhagic shock: A role for uric acid.

Multiple organ failure can develop after hemorrhagic shock (HS). Uric acid (UA) is released from dying cells and can be proinflammatory. We hypothesized that UA could be an alternative mediator of organ apoptosis and inflammation after HS. Ventilated male Wistar rats were used for the HS model. Two durations of shock (5 minutes vs. 60 minutes) were compared, and shams were instrumented only; animals were resuscitated and observed for 24 hours/72 hours. Caspases-(8/3), myeloperoxidase (MPO), TNF-α were measured in lungs and kidneys. Plasma UA and cytokine (IL-1β, IL-18, TNF-α) were measured. A second set of animals were randomized to vehicle versus Rasburicase intraperitoneal intervention (to degrade UA) during resuscitation. Another group received exogenous UA intraperitoneally without HS. Measures mentioned above, in addition to organs UA, were performed at 24 hours. In vitro, caspases-(8/3) activity was tested in epithelial cells exposed to UA. Hemorrhagic shock increased organ (kidney and lung) TNF-α, MPO, and caspases activity in various patterns while caspase-8 remained elevated over time. Hemorrhagic shock led to increased plasma UA at 2 hours, which remained high until 72 hours; TNF-α and IL-18 were elevated at 24 hours. The exogenous UA administration in sham animals reproduced the activation of caspase-8 and MPO in organs, and TNF-α in the lung. The increased plasma and organ UA levels, plasma and lung TNF-α, as well as organ caspase-(8/3) and MPO, observed at 24 hours after HS, were prevented by the administration of Rasburicase during resuscitation. In vitro, soluble UA induced caspases-(3/8) activity in epithelial cells. Uric acid is persistently high after HS and leads to the activation of caspases-8 and organ inflammation; these can be prevented by an intervention to degrade UA. Therefore, UA is an important biomarker and mediator that could be considered a therapeutic target during HS resuscitation in human.