IL-1β In Bronchoalveolar Lavage Fluid Research Articles

The SMAC mimetic birinapant alleviates lipopolysaccharide-induced acute lung injury by inhibiting MAPK signaling

The second mitochondria-derived activator of caspases (SMAC) mimetic birinapant attenuated liver injury by inhibited the degradation of tumor necrosis factor receptor-associated factor 3 (TRAF3) and activation of mitogen-activated protein kinase (MAPK) signaling pathway in liver macrophage, but its role in LPS induced acute lung injury (ALI) is not understood. The present study was to investigate the effects of birinapant on ALI and its possible mechanism. A dose of birinapant (30 mg/kg) or a vehicle was administered intravenously 24 hours before LPS (100 μg) stimulation in mice. The levels of TNF-α, IL-6 and IL-1β in bronchoalveolar lavage fluid (BALF) were measured by ELISA. The infiltrated macrophages and expression of monocyte chemoattractant protein-1 (MCP-1) was determined by immunohistochemistry staining in the lung tissues. The JNK and p38 MAPK activation, protein expression and K48-linked polyubiquitination of TRAF3 were determined in alveolar macrophage cell line (MH-S cells) after 1μg/ml LPS stimulation. The results showed that the birinapant down-regulated the levels of TNF-α, IL-6 and IL-1β in the BALF. In addition, birinapant markedly inhibited macrophages infiltration and MCP-1 protein expression in lung tissues. At last, birinapant suppressed the MAPKsignaling pathway and K48-linked ubiquitinated degradation of TRAF3 in MH-S cells after LPS administration. In conclusion, the results proved that birinapant protected against LPS-induced ALI through inhibiting MAPK activation and K48-linked ubiquitination of TRAF3 in alveolar macrophages.

Expression analysis of inflammatory factors in artificial quartz stone plate processing silicosis patients

Objective: To investigate the levels of tumor necrosis factor-alpha (TNF-α), interleukin-6 (IL-6) and interleukin-1beta (IL-1β) in the plasma and bronchoalveolar lavage fluid of silicosis patients with artificial quartz stone plate processing. Methods: In January 2022, 10 patients with artificial quartz stone plate processing silicosis and 20 patients with common silicosis who were hospitalized and diagnosed in a hospital at Zhejiang Province from June 2019 to December 2021 were retrospectively selected as the research objects, and 30 healthy people were selected as the control group during the same period. Plasma of all subjects and bronchoalveolar lavage fluid of all patients were collected. The levels of TNF-α, IL-6 and IL-1β in plasma and bronchoalveolar lavage fluid were detected by enzyme-linked immunosorbent assay and were analyzed. Results: The levels of TNF-α, IL-6 and IL-1β in the plasma of patients with silicosis were higher than those of the control group (P<0.05), and the levels of TNF-α and IL-1β in the plasma of silicosis patients with artificial quartz stone plate processing were higher than those of common silicosis patients (P<0.05). The levels of TNF-α and IL-1β in plasma of artificial quartz stone plate processing silicosis patients were higher than those of common silicosis patients at the same silicon stage (P<0.05). The levels of IL-1β in bronchoalveolar lavage fluid of silicosis patients with artificial quartz stone plate processing was higher than that of patients with common silicosis (P<0.05) . Conclusion: The levels of TNF-α, IL-6 and IL-1β in silicosis patients with artificial quartz stone plate processing are higher than those in patients with common silicosis, which may be related to dust components they are exposed to.

Physalin A alleviates inflammation and oxidative stress in mouse infantile pneumonia by inhibiting JAK/STAT3 and NF κB pathways

Purpose: To investigate the effect of physalin A on infantile pneumonia in mice.&#x0D; Methods: A mouse model of infantile pneumonia was established via intraperitoneal injection of lipopolysaccharide and verified using hematoxylin and eosin staining. Lipopolysaccharide-stimulated mice were then administered physalin A. The total protein content, number of cells, and levels of inflammatory-factor in bronchoalveolar lavage fluid (BALF) were determined. Inflammation and oxidative stress levels in lung tissues were determined by enzyme-linked immunosorbent assay (ELISA).&#x0D; Results: Lipopolysaccharide injection induced shrinking of pulmonary alveoli in mice, but physalin A administration ameliorated the histopathologic damage in lung tissues and significantly reduced the total protein content and number of cells in the BALF of lipopolysaccharide-stimulated mice (p &lt; 0.001). Moreover, physalin A also significantly down-regulated the levels of tumor necrosis factor-α, interleukin (IL)-6, IL-18, and IL-1β in BALF and lung tissues of lipopolysaccharide-treated mice (p &lt; 0.001). Physalin A attenuated lipopolysaccharide-induced increases in malondialdehyde and myeloperoxidase as well as decreases in superoxide dismutase and glutathione in mouse lung tissues. Additionally, physalin A reduced the levels of p-JAK1, p-STAT3, and p-p65 in lung tissues of lipopolysaccharide-treated mice.&#x0D; Conclusion: Physalin A exerts anti-inflammatory and anti-oxidant effect on lipopolysaccharide-induced lung injury in mice through the inactivation of JAK/STAT3 and NF-κB pathways. However, the effect of Physalin A on inflammation and oxidative stress in lipopolysaccharide-induced A549 cells will need to be investigated in further studies.&#x0D;

C57Bl/6N mice have an attenuated lung inflammatory response to dsRNA compared to C57Bl/6J and BALB/c mice

BackgroundLower respiratory infections caused by ssRNA viruses are a major health burden globally. Translational mouse models are a valuable tool for medical research, including research on respiratory viral infections. In in vivo mouse models, synthetic dsRNA can be used as a surrogate for ssRNA virus replication. However, studies investigating how genetic background of mice impacts the murine lung inflammatory response to dsRNA is lacking. Hence, we have compared lung immunological responses of BALB/c, C57Bl/6N and C57Bl/6J mice to synthetic dsRNA.MethodsdsRNA was administered intranasally to BALB/c, C57Bl/6N and C57Bl/6J mice once/day for three consecutive days. Lactate dehydrogenase (LDH) activity, inflammatory cells, and total protein concentration were analyzed in bronchoalveolar lavage fluid (BALF). Pattern recognition receptors levels (TLR3, MDA5 and RIG-I) were measured in lung homogenates using RT-qPCR and western blot. Gene expression of IFN-β, TNF-α, IL-1β and CXCL1 was assessed in lung homogenates by RT-qPCR. ELISA was used to analyze protein concentrations of CXCL1 and IL-1β in BALF and lung homogenates.ResultsBALB/c and C57Bl/6J mice showed infiltration of neutrophils to the lung, and an increase in total protein concentration and LDH activity in response to dsRNA administration. Only modest increases in these parameters were observed for C57Bl/6N mice. Similarly, dsRNA administration evoked an upregulation of MDA5 and RIG-I gene and protein expression in BALB/c and C57Bl/6J, but not C57Bl/6N, mice. Further, dsRNA provoked an increase in gene expression of TNF-α in BALB/c and C57Bl/6J mice, IL-1β only in C57Bl/6N mice and CXCL1 exclusively in BALB/c mice. BALF levels of CXCL1 and IL-1β were increased in BALB/c and C57Bl/6J mice in response to dsRNA, whereas the response of C57Bl/6N was blunt. Overall, inter-strain comparisons of the lung reactivity to dsRNA revealed that BALB/c, followed by C57Bl/6J, had the most pronounced respiratory inflammatory responses, while the responses of C57Bl/6N mice were attenuated.ConclusionsWe report clear differences of the lung innate inflammatory response to dsRNA between BALB/c, C57Bl/6J and C57Bl/6N mice. Of particular note, the highlighted differences in the inflammatory response of C57Bl/6J and C57Bl/6N substrains underscore the value of strain selection in mouse models of respiratory viral infections.

Exploring the treatment of sepsis-associated acute lung injury with Liangge Powder via ERK1/2 and PI3K/AKT pathways: based on network pharmacology and whole animal experimentation

Objective: To investigate the therapeutic effect and mechanism of Liangge Powder against sepsis-induced acute lung injury (ALI) . Methods: From April to December 2021, the key components of Liangge Powder and its targets against sepsis-induced ALI were analyzed by network pharmacology, and to enrich for relevant signaling pathways. A total of 90 male Sprague-Dawley rats were randomly assigned to sham-operated group, sepsis-induced ALI model group (model group), Liangge Powder low, medium and high dose group, ten rats in the sham-operated group and 20 rats in each of the remaining four groups. Sepsis-induced ALI model was established by cecal ligation and puncture. Sham-operated group: gavage with 2 ml saline and no surgical treatment. Model group: surgery was performed and 2 ml saline was gavaged. Liangge Powder low, medium and high dose groups: surgery and gavage of Liangge Powder 3.9, 7.8 and 15.6 g/kg, respectively. To measure the wet/dry mass ratio of rats lung tissue and evaluate the permeability of alveolar capillary barrier. Lung tissue were stained with hematoxylin and eosin for histomorphological analysis. The levels of tumor necrosis factor-alpha (TNF-α), interleukin (IL) -6 and IL-1β in bronchoalveolar lavage fluid (BALF) were measured by enzyme-linked immunosorbent assay. The relative protein expression levels of p-phosphatidylinositol 3-kinase (PI3K), p-protein kinase B (AKT), and p-ertracellular regulated protein kinases (ERK) were detected via Western blot analysis. Results: Network pharmacology analysis indicated that 177 active compounds of Liangge Powder were selected. A total of 88 potential targets of Liangge Powder on sepsis-induced ALI were identified. 354 GO terms of Liangge Powder on sepsis-induced ALI and 108 pathways were identified using GO and KEGG analysis. PI3K/AKT signaling pathway was recognized to play an important role for Liangge Powder against sepsis-induced ALI. Compared with the sham-operated group, the lung tissue wet/dry weight ratio of rats in the model group (6.35±0.95) was increased (P<0.001). HE staining showed the destruction of normal structure of lung tissue. The levels of IL-6 [ (392.36±66.83) pg/ml], IL-1β [ (137.11±26.83) pg/ml] and TNF-α [ (238.34±59.36) pg/ml] were increased in the BALF (P<0.001, =0.001, <0.001), and the expression levels of p-PI3K, p-AKT and p-ERK1/2 proteins (1.04±0.15, 0.51±0.04, 2.31±0.41) were increased in lung tissue (P=0.002, 0.003, 0.005). The lung histopathological changes were reduced in each dose group of Liangge Powder compared with the model group. Compared with the model group, the wet/dry weight ratio of lung tissue (4.29±1.26) was reduced in the Liangge Powder medium dose group (P=0.019). TNF-α level [ (147.85±39.05) pg/ml] was reduced (P=0.022), and the relative protein expression levels of p-PI3K (0.37±0.18) and p-ERK1/2 (1.36±0.07) were reduced (P=0.008, 0.017). The wet/dry weight ratio of lung tissue (4.16±0.66) was reduced in the high-dose group (P=0.003). Levels of IL-6, IL-1β and TNF-α[ (187.98±53.28) pg/ml, (92.45±25.39) pg/ml, (129.77±55.94) pg/ml] were reduced (P=0.001, 0.027, 0.018), and relative protein expression levels of p-PI3K, p-AKT and p-ERK1/2 (0.65±0.05, 0.31±0.08, 1.30±0.12) were reduced (P=0.013, 0.018, 0.015) . Conclusion: Liangge Powder has therapeutic effects in rats with sepsis-induced ALI, and the mechanism may be related to the inhibition of ERK1/2 and PI3K/AKT pathway activation in lung tissue.

1,2,3,4,6-O-Pentagalloylglucose Protects against Acute Lung Injury by Activating the AMPK/PI3K/Akt/Nrf2 Pathway.

An acute lung injury (ALI) is a serious lung disease with a high mortality rate, warranting the development of novel therapies. Previously, we reported that 1,2,3,4,6-O-pentagalloylglucose (PGG) could afford protection against ALI, however, the PGG-mediated protective effects remain elusive. Herein, PGG (60 and 30 mg/kg) markedly inhibited the lung wet/drug weight ratio and attenuated histological changes in the lungs (p &lt; 0.05). A pretreatment with PGG (60 and 30 mg/kg) reduced the number of total leukocytes and the production of pro-inflammatory cytokines IL-6 and IL-1β in bronchoalveolar lavage fluid (p &lt; 0.05). In addition, PGG (60 and 30 mg/kg) also attenuated oxidative stress by reducing the formation of formation and the depletion of superoxide dismutase to treat an ALI (p &lt; 0.05). To further explore the PGG-induced mechanism against an ALI, we screened the PGG pathway using immunohistochemical analysis, immunofluorescence assays, and Western blotting (WB). WB revealed that the expression levels of adenosine monophosphate-activated protein kinase phosphorylation (p-AMPK), phosphoinositide 3-kinase (PI3K), protein kinase B phosphorylation (P-Akt), and nuclear factor erythroid 2-related factor (Nrf2) were significantly higher in the PGG group (60 and 30 mg/kg) than in the lipopolysaccharide group (p &lt; 0.05); these findings were confirmed by the immunohistochemical and immunofluorescence results. Accordingly, PGG could be effective against an ALI by inhibiting inflammation and oxidative stress via AMPK/PI3K/Akt/Nrf2 signaling, allowing for the potential development of this as a natural drug against an ALI.

Heparin-Binding Protein Aggravates Acute Lung Injury in Septic Rats by Promoting Macrophage M1 Polarization and NF-κB Signaling Pathway Activation.

Objective Heparin-binding protein (HBP) plays an important role in sepsis and is a prognostic biomarker in patients with sepsis, but the role of HBP in the pathogenesis of sepsis-associated acute lung injury (ALI) remains unclear. This study aimed to investigate the role of HBP in sepsis-induced ALI and its underlying molecular mechanisms. Methods The cecal ligation and puncture (CLP) model was used to induce ALI in mice and randomly divided into 4 groups: control group, CLP (rats treated with cecal ligation and puncture), HBP (rats treated with CLP and HBP injection), and HBP + UFH (rats treated with CLP and injection of HBP and unfractionated heparin). Subsequently, HBP expression in rat serum and lung tissues was detected by qRT-PCR, edema and pathological changes in lung tissue by lung wet-to-dry weight ratio (W/D) and HE staining, myeloperoxidase (MPO) and superoxide dismutase (SOD) activities in lung tissues by detection kits. Additionally, ELISA and western blot were applied for the determination of IL-6, TNF-α, and IL-1β expression in rat bronchoalveolar lavage fluid, and iNOS, Arg-1, Mrc1, NF-κBp65, IKKα, IκBα, and p-IκBα expression in lung tissues. Results The expression levels of HBP in serum and lung tissues of rats in the HBP group were significantly increased, the lung tissues were severely injured, accompanied by a significant increase in MPO activity but a significant decrease in SOD activity, and the levels of IL-6, TNF-α, and IL-1β in bronchoalveolar lavage fluid were significantly increased. In addition, the expression levels of iNOS, NF-κB p65, IKKα, and p-IκBα in the lung tissues of rats in the HBP group were significantly increased, while the addition of unfractionated heparin reversed the above results. Conclusion HBP aggravates ALI in septic rats, and its mechanism may be related to the promotion of macrophage M1 polarization and activation of the NF-κB signaling pathway.

Exosome from BMMSC Attenuates Cardiopulmonary Bypass-Induced Acute Lung Injury Via YAP/β-Catenin Pathway: Downregulation of Pyroptosis.

Acute lung injury (ALI) accompanied with systemic inflammatory response is an important complication after cardiopulmonary bypass (CPB). Pyroptosis, which is induced by the secretion of inflammatory factors, has been implicated in ALI. However, recent studies have suggested that bone marrow mesenchymal stem cell-derived exosomes (BMMSC-Exo) can ameliorate ALI, but the mechanism is poorly understood. Therefore, we aim to examine the effects of BMMSC-Exo in CPB-induced ALI, and its underlying mechanism. CPB rat models (male Sprague-Dawley rats) were administered BMMSC-Exo intravenously before induction of ALI. Lung tissue, bronchoalveolar lavage fluid (BALF), and alveolar macrophage (AM) were collected after the treatments for further analysis, and rat AM NR8383 cells were used for in vitro study. HE staining was performed to detect macrophage infiltration. Western blot was used to detect related proteins expression. And ELISA assay was performed to investigate secretion of inflammatory factors. These results showed that BMMSC-Exo treatment ameliorated macrophage infiltration and oxidative stress, and downregulated expression of pyroptosis-related proteins, including NLRP3, cleaved caspase-1, and GSDMD-N, in the lung tissue and AM, as well as decreased the secretion of IL-18 and IL-1β in BALF. Moreover, BMMSC-Exo activated YAP/β-catenin signaling pathway. Overall, these findings of this study indicated that BMMSC-Exo suppressed CPB-induced pyroptosis in ALI by activating YAP/β-catenin axis, which could be a novel strategy for lung protection during CPB.

Dopamine relieves inflammatory responses through the D2 receptor after electroacupuncture at ST36 in a mouse model of chronic obstructive pulmonary disease.

To detect the role of dopamine in the anti-inflammatory effect of electroacupuncture (EA) at ST36 in a mouse model of chronic obstructive pulmonary disease (COPD). Twenty-eight male BALB/c mice were randomly divided into the control group, model group, sham EA (sham) group or ST36 EA (ST36) group in a 1:1:1:1 ratio (n = 7 each). The COPD mouse model was established through cigarette smoke (CS) exposure for 12 weeks. During the last 2 weeks, EA was applied at a sham point location or ST36 before CS exposure. Lung function, histopathological changes, inflammatory cell counts in bronchoalveolar lavage fluid (BALF), inflammatory cytokines in BALF, plasma, lung tissue homogenate (LTH), and plasma dopamine levels were detected in the different groups. Furthermore, the role of different dopamine receptors was explored through intraperitoneal injections of non-specific dopamine receptor antagonist chlorpromazine, specific dopamine D1 receptor antagonist SCH 23390 and specific dopamine D2 receptor antagonist eticlopride hydrochloride prior to ST36 EA and CS exposure. EA at ST36 improved lung function, alleviated lung and systemic inflammatory responses by reducing inflammatory cells and cytokines including tumor necrosis factor (TNF)-α, interleukin (IL)-8 and IL-1β in BALF, plasma and lung tissue in this COPD mouse model. Plasma dopamine was greatly increased after EA at ST36, negatively correlated with lung histological lesions and inflammatory cytokine levels, and positively correlated with mice body weight and lung function indicators. Chlorpromazine and eticlopride hydrochloride inhibited the anti-inflammatory effect of EA at ST36, while SCH 23390 showed no neutralizing effect. EA at ST36 could alleviate inflammation in this mouse model of COPD through the dopamine D2 receptor pathway.

Role of angiotensin-converting enzyme 2 in fine particulate matter-induced acute lung injury

Fine particulate matter (PM2.5) pollution poses significant health concerns worldwide and can cause respiratory diseases. However, how it causes health problems is still poorly understood. Angiotensin-converting enzyme (ACE)2 is a terminal carboxypeptidase implicated in the functions of renin-angiotensin system (RAS) and plays a crucial role in the control of lung inflammation. To investigate whether ACE2 functions in PM2.5-induced lung inflammation, wild-type (WT) C57BL/6J mice and ACE2 knock-out (KO) mice were intratracheally instilled with PBS or PM2.5 suspension for 3 consecutive days, respectively. The concentrations of cytokines in bronchoalveolar lavage fluid (BALF) were determined by ELISA. The expression of ACE2 and ACE and activation of inflammatory signaling pathways in lung tissues were evaluated by immunofluorescence staining and Western blotting. We found that PM2.5 exposure increased ACE2 expression. Loss of ACE2 significantly elevated the levels of total proteins, total cells, and the concentrations of MCP-1, IL-1β in BALF after PM2.5 challenge. Additionally, loss of ACE2 enhanced lung pathologies, airway resistance, and inflammatory signaling activation. Collectively, loss of ACE2 exacerbates PM2.5-induced acute lung injury in mice.

Circular RNA-CDR1as is involved in lung injury induced by long-term formaldehyde inhalation

Objective: Formaldehyde (FA) is known to induce lung injury, but the underlying molecular mechanism remains largely unclear. CDR1as is an important member of the circular RNAs (circRNAs) family and functions as miRNA sponges with gene-regulatory potential. Our earlier circRNA microarray data showed CDR1as was highly expressed in lung tissue exposed to FA. However, the mechanism of circRNA-CDR1as mediates the FA-exposed lung injury is still unclear. This study aimed to explore the role of CDR1as in lung injury. Materials and methods: In this study, FA was inhaled at doses of 0.5, 2.46, and 5 mg/m3, respectively. After exposure 8 weeks, lung histopathological examination, lung injury score, and IL-1β in bronchoalveolar lavage fluid (BALF) were determined. The expressions of CDR1as, rno-miR-7b and Atg7 were detected and the potential interaction of circRNA/miRNA/mRNA was predicted by bioinformatics analysis, including drawing circRNA/miRNA/mRNA interaction network, GO and KEGG analysis. Results: Our results indicated FA inhalation upregulated the expression of CDR1as in lung tissues in a dose-dependent manner while the expression of rno-miR-7b decreased and Atg7 increased. Moreover, the alteration of CDR1as was positively correlated with lung injury. Discussion and conclusions: CircRNA/miRNA/mRNA prediction further explained the possible effect mechanisms of CDR1as. These data implicated that CDR1as might be a critical regulator involved in lung injury induced by FA.

Mechanical Ventilation Exacerbates Poly (I:C) Induced Acute Lung Injury: Central Role for Caspase-11 and Gut-Lung Axis.

BackgroundThe mechanisms by which moderate tidal volume ventilation (MTV) exacerbates preexisting lung injury are unclear. We hypothesized that systemic endotoxemia via the gut-lung axis would lead to non-canonical and canonical inflammasome activation and pyroptosis in a two-hit model involving polyinosinic-polycytidylic acid (Poly(I:C)), a synthetic analog of dsRNA and MTV and that this would associate with acute lung injury (ALI).MethodsAnesthetized mice were administered Poly(I:C) intratracheally and then 6 h later, they were mechanically ventilated for 4 h with otherwise non-injurious MTV (10ml/kg). Changes in intestinal and alveolar capillary permeability were measured. Further documentation of ALI was assessed by evans blue albumin permeability, protein and IL-1 family concentration in bronchoalveolar lavage fluid (BALF) or plasma, and histopathology in cohorts of wildtype (WT), whole body genetically ablated caspase-11 (caspase-11-/-), caspase-1/caspase-11 double knockout (caspase-1/11-/-), gasdermin D (GSDMD)-/-, nucleotide-binding domain leucine-rich repeat-containing protein 3 (NLRP3)-/- and advanced glycosylation end product-specific receptor (RAGE) -/- mice.ResultsNon-injurious MTV exacerbated the mild lung injury associated with Poly(I:C) administration. This included the disruption of alveolar-capillary barrier and increased levels of interleukin (IL)-6, high mobility group proteins 1 (HMGB-1), IL-1β in BALF and IL-18 in plasma. Combined (Poly(I:C)-MTV) injury was associated with increase in gastrointestinal permeability and endotoxin in plasma and BALF. Poly(I:C)-MTV injury was sensitive to caspase-11 deletion with no further contribution of caspase-1 except for maturation and release of IL-18 (that itself was sensitive to deletion of NLRP3). Combined injury led to large increases in caspase-1 and caspase-11. Genetic ablation of GSDMD attenuated alveolar-capillary disruption and release of cytokines in combined injury model.ConclusionsThe previously noted exacerbation of mild Poly(I:C)-induced ALI by otherwise non-injurious MTV is associated with an increase in gut permeability resulting in systemic endotoxemia. The gut-lung axis resulted in activation of pulmonary non-canonical (cytosolic mediated caspase-11 activation) and canonical (caspase-1) inflammasome (NLRP3) mediated ALI in this two-hit model resulting in GSDMD sensitive alveolar capillary barrier disruption, pyroptosis (alveolar macrophages) and cytokine maturation and release (IL-1β; IL-18). Pharmacologic strategies aimed at disrupting communication between gut and lung, inhibition of inflammasomes or GSDMD in pyroptosis may be useful in ALI.

Toxicological implication of prostaglandin transporter SLCO2A1 inhibition by cigarette smoke in exacerbation of lung inflammation

We reported that bleomycin (BLM)-induced pulmonary fibrosis was exacerbated in the prostaglandin transporter gene (Slco2a1)-deficient mice (Slco2a1(−/−)). Because cigarette smoke (CS) contributes to creating a profibrotic milieu in the respiratory region, the present study aimed to investigate the impact of CS on SLCO2A1-associated pathogenesis in the lungs of BLM-instilled mice. Bronchoalveolar lavage (BAL) fluid cell analysis indicated more severe inflammation in Slco2a1(−/−) on day 5 after BLM intratracheal instillation, and Slco2a1 deletion increased mRNA expression of pro-inflammatory cytokines (Tnf-α and Il-1β) and chemokine (Ccl5) in BAL cells. Male Slco2a1(−/−) exhibited significantly higher amounts of released Il-1β in BAL fluid, compared with female Slco2a1(−/−), male or female Slco2a1(+/+) group. The amount of PGE2 collected in BAL fluid tended to increase in Slco2a1(−/−) compared with Slco2a1(+/+) group, whereas the PGE2 concentrations in lung tissues were comparable between both groups. Besides, PGE2 accumulated more in BAL fluid of male than that of female mice. Therefore, Slco2a1-deficient male mice were found to be more susceptible to BLM-treatment. Moreover, CS extracts (CSE) significantly reduced initial PGE2 uptake by rat type1 alveolar epithelial cell-like (AT1-L) cells and human SLCO2A1-transfected cells. Exposure of AT1-L cells to CSE resulted in decreased mRNA expression of Slco2a1, suggesting that CS modulates SLCO2A1 function. These results indicate that exacerbated lung inflammation is attributed to an increase in Il-1β peptide and PGE2 accumulation in the alveolar space, which exhibits a male predominance. SLCO2A1 inhibition by CSE is considered to be a new rationale for the lung toxicity of CS.

Fisetin alleviates sepsis-induced multiple organ dysfunction in mice via inhibiting p38 MAPK/MK2 signaling.

Sepsis-induced multiple organ dysfunction and inflammatory response are life-threatening symptoms without effective treatment. Fisetin, a dietary flavonoid extracted from berries and family Fabaceae, has displayed neuroprotective and anti-oxidant activities. In this study we investigated whether fisetin exerted a protective effect against sepsis-induced multiple organ dysfunction in mouse cecum ligation and puncture (CLP) model. The mice were injected with fisetin (10 mg/kg, ip) 0.5 h prior to CLP, and sacrificed 18 h after CLP. We found that fisetin administration significantly alleviated CLP-induced lung, liver and kidney injury, as well as the expression levels of interleukin (IL)-6, tumor necrosis factor (TNF)-α and IL-1β in bronchoalveolar lavage fluid (BALF). In lipopolysaccharide (LPS)-treated mouse bone marrow-derived macrophages (BMDMs), application of fisetin (3–10 μM) dose-dependently inhibited the expression levels of IL-6, TNF-α, IL-1β, and inducible nitric oxide synthase (iNOS). Furthermore, fisetin dose-dependently inhibited the phosphorylation of p38 MAPK, MK2, and transforming growth factor-β-activated kinase (TAK) 1 via attenuating the interaction between TAK1 and TAK-binding proteins (TAB) 1. These results demonstrate that fisetin is a promising agent for protecting against sepsis-induced inflammatory response and organ injury via inhibiting macrophage activation.

Hydrogen Sulfide Attenuates Particulate Matter-Induced Emphysema and Airway Inflammation Through Nrf2-Dependent Manner.

PurposeTo investigate whether hydrogen sulfide provide protective effects on atmosphere particulate matter (PM)-induced emphysema and airway inflammation and its mechanism.MethodsWild type C57BL/6 and Nrf2 knockout mice were exposed to PM (200 µg per mouse). Hydrogen sulfide or propargylglycine were administered by intraperitoneal injection respectively 30 min before PM exposure, mice were anesthetized 29th day after administration. Mice emphysema, airway inflammation, and oxidative stress were evaluated, the expression of NLRP3, active caspase-1, and active caspase-3 were detected. Alveolar epithelial A549 cells line were transfected with control small interfering RNA (siRNA) or Nrf2 siRNA and then incubated with or without hydrogen sulfide for 30 min before exposed to fine particulate matter for 24 h, cell viability, terminal deoxynucleotidyl transferase deoxyuridine triphosphate nick-end labeling (TUNEL) assay, the secretion of interleukin (IL)-1β, ASC speck formation, the expression level of NLRP3, active caspase-1, and active caspase-3 were measured.ResultsPM significantly increased mice emphysema and airway inflammation measured by mean linear intercept, alveolar destroy index and total cell, neutrophil counts, cytokines IL-6, tumor necrosis factor (TNF)-α, CXCL1, IL-1β in bronchoalveolar lavage fluid. PM-induced mice emphysema and airway inflammation was greatly attenuated by hydrogen sulfide, while propargylglycine aggravated that. PM-induced oxidative stress was reduced by hydrogen sulfide as evaluated by 8-OHdG concentrations in lung tissues. The expression of NLRP3, active caspase-1, and active caspase-3 enhanced by PM were also downregulated by hydrogen sulfide in mice lung. The protective effect of hydrogen sulfide on emphysema, airway inflammation, inhibiting oxidative stress, NLRP3 inflammasome formation, and anti-apoptosis was inhibited by Nrf2 knockout in mice. Similarly, hydrogen sulfide attenuated the secretion of IL-1β, NLRP3 expression, caspase-1 activation, ASC speck formation, and apoptosis caused by fine particulate matter exposure in A549 cells but not in Nrf2 silenced cells.ConclusionHydrogen sulfide played a protect role in PM-induced mice emphysema and airway inflammation by inhibiting NLRP3 inflammasome formation and apoptosis via Nrf2-dependent pathway.

Does p-coumaric acid improve cardiac injury following LPS-induced lung inflammation through miRNA-146a activity?

In cardiovascular diseases, inflammatory response plays an important role and affects heart function. As a flavonoid compound, p-coumaric acid (pCA), commonly exists in many fruits and vegetables and has a therapeutic effect on inflammatory diseases due to its anti-inflammatory properties. The purpose of the present study was to investigate pCA anti-inflammatory effect and the miRNAs (miRs) signaling pathway involved in cardiac inflammation following lipopolysaccharide-induced acute lung injury (ALI). Thirty-two Sprague-Dawley male rats were divided into 4 groups: control (received saline for 10 days, i.p.), LPS (received saline for 10 days+5 mg/kg LPS on day 8, intratracheally), pCA (received pCA 100 mg/kg for 10 days, ip), and LPS+pCA (received LPS+pCA). The level of IL-1β, IL-18 in heart tissue and IL-1β in bronchoalveolar lavage fluid (BALF) was determined by ELISA kits. Also the level of lactate dehydrogenase (LDH) in heart tissue and myeloperoxidase (MPO) in lung tissue were measured, and pCA effect on miR- 146a in heart tissue was analyzed. Data showed that 100 mg/kg of pCA significantly suppressed LDH activity (p<0.05), IL-18 (p<0.05) and IL-1β (p<0.01) level in heart tissue. Also, in BAL, IL-1β and MPO levels were significantly reduced (p<0.001). Finally, pCA modulated activation of miR-146a (p<0.05) in LPS -induced cardiac injury. These findings indicated that LPS causes cardiac dysfunction and pre-treatment with pCA, as an anti-inflammatory agent, improved cardiac inflammation through modulation of miR-146a, and reducing cytokines and LDH activity.

Acacia catechu (L.f.) Willd and Scutellaria baicalensis Georgi extracts suppress LPS-induced pro-inflammatory responses through NF-кB, MAPK, and PI3K-Akt signaling pathways in alveolar epithelial type II cells.

Acacia catechu (L.f.) Willd (ACW) and Scutellaria baicalensis Georgi (SBG) are one of the most famous couplet Chinese medicines, widely used for treating infantile cough, phlegm, and fever caused by pulmonary infection. However, the underlying molecular mechanism of their anti-inflammatory activity has not been determined. The aim of this study was to evaluate the protective effect of this couplet Chinese medicines (ACW-SBG) on lipopolysaccharide (LPS)-induced inflammatory responses in acute lung injury (ALI) model of rats and the potential molecular mechanisms responsible for anti-inflammatory activities in alveolar epithelial type II cells (AEC-II). Standardization of the 70% ethanol extract of ACW and SBG was performed by using a validated reversed-phase high-pressure liquid chromatography method. Rats were pretreated with ACW-SBG for 7days prior to LPS challenge. We assessed the effects of ACW-SBG on the LPS-induced production of tumor necrosis factor alpha (TNF-α) and interleukin 1 beta (IL-1β) in the bronchoalveolar lavage fluid (BALF). The wet-to-dry weight ratio was calculated, and hematoxylin and eosin staining of lung tissue was performed. Cell viability of AEC-II was measured by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay. Real-time quantitative reverse transcription polymerase chain reaction assay was carried out to quantify the relative gene expression of TNF-α and IL-1β in AEC-II. The western blotting analysis was executed to elucidate the expression of mediators linked to nuclear factor-kappa B (NF-κB), mitogen-activated protein kinase (MAPK), and phosphatidylinositol-3 kinase-protein kinase B (PI3K-Akt) signaling pathways. ACW-SBG significantly decreased lung wet-to-dry weight ratio, ameliorated LPS-induced lung histopathological changes, and reduced the release of inflammatory mediators such as TNF-α and IL-1β in BALF. In AEC-II, we found that the expression of TNF-α mRNA was also inhibited by ACW-SBG. ACW-SBG blocked NF-κB activation by preventing the phosphorylation of NF-κB (p65) as well as the phosphorylation and degradation of the inhibitor of kappa B kinase. ACW-SBG extracts also inhibited the phosphorylation of respective MAPKs (c-Jun N-terminal kinase, extracellular signal-regulated kinase, and p38) as well as Akt. The present study demonstrated that ACW-SBG played a potent anti-inflammatory role in LPS-induced ALI in rats. The potential molecular mechanism was involved in attenuating the NF-κB, MAPKs, and PI3K-Akt signaling pathways in LPS-induced AEC-II.

Cardamine komarovii flower extract reduces lipopolysaccharide-induced acute lung injury by inhibiting MyD88/TRIF signaling pathways.

In the present study, we investigated anti-inflammatory effect of Cardamine komarovii flower (CKF) on lipopolysaccharide (LPS)-induced acute lung injury (ALI). We determined the effect of CKF methanolic extracts on LPS-induced pro-inflammatory mediators NO and prostaglandin E2 (PGE2), production of pro-inflammatory cytokines (IL-1β, TNF-α, and IL-6), and related protein expression levels of MyD88/TRIF signaling pathways in peritoneal macrophages (PMs). Nuclear translocation of NF-κB-p65 was analyzed by immunofluorescence. For the in vivo experiments, an ALI model was established to detect the number of inflammatory cells and inflammatory factors (IL-1β, TNF-α, and IL-6) in bronchoalveolar lavage fluid (BALF) of mice. The pathological damage in lung tissues was evaluated through H&E staining. Our results showed that CKF can decrease the production of inflammatory mediators, such as NO and PGE2, by inhibiting their synthesis-related enzymes iNOS and COX-2 in LPS-induced PMs. In addition, CKF can downregulate the mRNA levels of IL-1β, TNF-α, and IL-6 to inhibit the production of inflammatory factors. Mechanism studies indicated that CKF possesses a fine anti-inflammatory effect by regulating MyD88/TRIF dependent signaling pathways. Immunocytochemistry staining showed that the CKF extract attenuates the LPS-induced translocation of NF-kB p65 subunit in the nucleus from the cytoplasm. In vivo experiments revealed that the number of inflammatory cells and IL-1β in BALF of mice decrease after CKF treatment. Histopathological observation of lung tissues showed that CKF can remarkably improve alveolar clearance and infiltration of interstitial and alveolar cells after LPS stimulation. In conclusion, our results suggest that CKF inhibits LPS-induced inflammatory response by inhibiting the MyD88/TRIF signaling pathways, thereby protecting mice from LPS-induced ALI.

Chronic arsenic exposure in drinking water interferes with the balances of T lymphocyte subpopulations as well as stimulates the functions of dendritic cells in vivo

The immunomodulatory properties of arsenic are nowadays supposed be associated with pathological injuries of this toxicant and the details have not been clarified. Our objective was to explore inflammation, differentiation of diverse T cell subsets, as well as the phenotypic molecules and functions of dendritic cells (DCs) by chronic arsenic exposure in vivo. We exposed different concentrations of arsenic (0, 0.1, 1 and 10 mg/L) in drinking water for 6 and 12 months in C57BL/6 mice. We first confirmed that low levels of arsenic induced excess inflammation evidenced by accumulation of macrophages and lymphocytes in bronchoalveolar lavage fluid (BALF), secretion of pro-inflammatory cytokine IL-1β in BALF and serum, as well as histological analysis. Flow cytometry analysis revealed that arsenic disturbed CD4/CD8 T-cell ratio in isolated pneumonocytes and splenocytes, as well as enhanced IFN-γ and reduced IL-4 in spleen. The mRNA expressions of transcription factors (T-bet, GATA3, ROR-γt) and cytokines (IFN-γ, IL-4, IL-10, IL-23, IL-22) showed the imbalanced Th1/Th2/Th17 differentiation in arsenic exposed lung and spleen. We further testified that arsenic enhanced the percentages of CD11c+ DCs, and promoted the expressions of antigen presentation molecule MHC II and cytokine IL-12, co-stimulatory molecules (CD86, CD80), and chemokine receptors (CCR7, CCR5) in vivo. Moreover, arsenic activated the expressions of immune-related MAPKs and NF-κB. Taken together, our study here demonstrated that chronic arsenic exposure could disrupt the immune homeostasis in vivo possibly by interfering with the differentiation of Th1/Th2/Th17 subsets as well as the function of DCs.

Apolipoprotein E is a concentration-dependent pulmonary danger signal that activates the NLRP3 inflammasome and IL-1β secretion by bronchoalveolar fluid macrophages from asthmatic subjects

House dust mite (HDM)-challenged Apoe-/- mice display enhanced airway hyperreactivity and mucous cell metaplasia. We sought to characterize the pathways that induce apolipoprotein E (APOE) expression by bronchoalveolar lavage fluid (BALF) macrophages from asthmatic subjects and identify how APOE regulates IL-1β secretion. Macrophages were isolated from asthmatic BALF and derived from THP-1cells and human monocytes. HDM-derived cysteine and serine proteases induced APOE secretion from BALF macrophages through protease-activated receptor 2. APOE at concentrations of less than 2.5nmol/L, which are similar to levels found in epithelial lining fluid from healthy adults, did not induce IL-1β release from BALF macrophages. In contrast, APOE at concentrations of 25nmol/L or greater induced nucleotide-binding oligomerization domain, leucine-rich repeat-containing protein (NLRP) 3 and pro-IL-1β expression by BALF macrophages, as well as the caspase-1-mediated generation of mature IL-1β secreted from cells. HDM acted synergistically with APOE to both prime and activate the NLRP3 inflammasome. In a murine model of neutrophilic airway inflammation induced by HDM and polyinosinic-polycytidylic acid, APOE reached a concentration of 32nmol/L in epithelial lining fluid, with associated increases in BALF IL-1β levels. APOE-dependent NLRP3 inflammasome activation in macrophages was primarily mediated through a potassium efflux-dependent mechanism. APOE can function as an endogenous, concentration-dependent pulmonary danger signal that primes and activates the NLPR3 inflammasome in BALF macrophages from asthmatic subjects to secrete IL-1β. This might represent a mechanism through which APOE amplifies pulmonary inflammatory responses when concentrations in the lung are increased to greater than normal levels, which can occur during viral exacerbations of HDM-induced asthma characterized by neutrophilic airway inflammation.