Apoptosis In Lung Tissues Research Articles

Mitigation of allergic asthma in mice: A compound mixture comprising luteolin, arbutin, and marmesin from Gerbera Piloselloides Herba by suppression of PI3K/Akt pathway

BackgroundGerberae Piloselloidis Herba (GPH) exhibits notable efficacy in alleviating allergic asthma. Previous studies in our research have identified a mixture of luteolin, arbutin, and marmesin as effective components of GPH in treating allergic asthma. However, the underlying mechanism remains unclear. This study aims to elucidate the molecular mechanism of these active components. MethodUsing an ovalbumin (OVA)-induced allergic asthma mouse model, various treatment groups were administered, including GPH, the active component mixture (termed "Mixture") containing luteolin, arbutin, and marmesin, and a positive drug (dexamethasone, DEX). Relevant indices were assessed, including behavioral characteristics, inflammatory cell counts, cytokine levels, histopathological examination of lung tissue, apoptosis, and expression of key proteins such as Caspase-3, Bax, Bcl-2, PI3K, p-PI3K, Akt, and p-Akt. The effect of the Mixture on the PI3K/Akt signaling pathway was further verified using the PI3K inhibitor LY294002. ResultsThe Mixture significantly alleviated asthma symptoms, decreased IgE levels, cytokine levels (IL-4, IL-5, IL-13 and TNF-α), and the number of inflammatory cells in serum or bronchoalveolar lavage fluid (BALF), leading to the alleviation of lung pathological lesions. Additionally, the Mixture reduced the expression of Bax and Caspase-3 while increasing Bcl-2 expression, resulting in mitigated apoptosis in lung tissue. Furthermore, there appeared a decrease in the levels of PI3K and p-PI3K, as well as the ratio of p-Akt to Akt in the Mixture group, indicating the suppression of PI3K and Akt phosphorylation. Interestingly, the effects of the Mixture were comparable to those of GPH, LY294002, or the combination of LY294002 with the Mixture. ConclusionThe study confirms that the Mixture containing luteolin, arbutin, and marmesin indeed alleviates allergic asthma induced by OVA in mice by suppressing the PI3K/Akt signaling pathway. These findings highlight the potential of the GPH-derived Mixture as a novel therapeutic for the treatment of allergic asthma.

Resolvin E1 and Inhibition of BLT2 Signaling Attenuate the Inflammatory Response and Improve One-Lung Ventilation-Induced Lung Injury.

One-lung ventilation (OLV) is a prevalently used technique to sustain intraoperative pulmonary function. Resolvin E1 (RvE1), a specialized pro-resolving lipid mediator, accelerates the resolution of inflammation in the lungs. However, its therapeutic effects on OLV-induced lung injury remain unclear. We initially developed an OLV rat model and treated it with RvE1. Subsequently, we assessed the wet/dry ratio of the lung tissue, performed hematoxylin and eosin staining, and calculated the ratio of polymorphonuclear cells to white blood cells in the bronchoalveolar lavage fluid. Additionally, we assessed apoptosis, inflammatory factor levels, and lung permeability in the rat lung tissues in the RvE1 treated and untreated groups and explored the molecular mechanisms mediated by RvE1. Our results indicated that RvE1 alleviated lung injury and inflammation and improved lung tissue apoptosis and permeability in OLV rats. Moreover, RvE1 suppressed the expression of the BLT1/2 signaling pathway and its ligands. The use of BLT2 and BLT1 inhibitors (LY255283 and U-75302, respectively) enhanced RvE1's anti-inflammatory effects and reduced lung injury. Furthermore, synergistic treatment with the BLT2 inhibitor and RvE1 provided grater benefits by more effectively inhibiting the NF-kB, p38 MAPK, and ERK pathways. RvE1 and the inhibition of BLT2 signalling reduce the inflammatory response and mitigate OLV-induced lung injury. These findings suggest a novel therapeutic pathway for managing OLV-related complications.

Overexpression of Parkin promotes the protective effect of mitochondrial autophagy on the lung of rats with exertional heatstroke

BackgroundThe roles of the Pink1/Parkin pathway and mitophagy in lung injury during heat stroke remain unclear. In this study, we investigated the role of Pink1/Parkin-mediated mitophagy in acute lung injury (ALI) in rats with exertional heat stroke (EHS). MethodsSixty Sprague Dawley rats were randomly divided into control (CON), control + Parkin overexpression (CON + Parkin), EHS, and EHS + Parkin overexpression (EHS + Parkin) groups. Parkin was overexpressed by injecting an adeno-associated virus carrying the Parkin gene into the tail vein, and a rat model of EHS was established. Pathological changes in the lung tissue were analyzed using microcomputed tomography (micro-CT), and the lung coefficient and pulmonary capillary permeability were measured. Enzyme-linked immunosorbent assay were used to determine the levels of interleukin-6 (IL-6), IL-1β, and tumor necrosis factor-α, and reactive oxygen species. The morphology of mitochondria in type Ⅱ epithelial cells of lung tissue was observed using transmission electron microscopy; and the apoptosis of lung tissue, the level of mitophagy, and the co-localization of Pink1 and Parkin were determined using immunofluorescence. The expression of Pink1, Parkin, mitofusin-2 (MFN2), phosphatase and tensin homolog (PTEN), PTEN-L, p62, and the autophagy marker microtubule-associated protein 1 light chain 3 (LC3) in rat lung tissue was measured by western blotting, and the ratio of LC3II/LC3I was calculated. ResultsCompared with the EHS group, the survival rate of rats in the EHS + Parkin group was significantly higher. Their lung coefficient and pulmonary vascular permeability decreased and the pathological changes were significantly alleviated (P <0.05). Their levels of inflammatory factors and reactive oxygen species were significantly decreased (P <0.05), and the degree of mitochondrial swelling in pulmonary type II epithelial cells was alleviated. The apoptosis of lung tissue was alleviated, the colocalization of Pink1 and Parkin, LC3 and Tom20 was enhanced, and the ratio of LC3-II/LC3-I increased. The expression of Pink1, MFN2, PTEN-L, and p62 decreased, whereas the expression of PTEN was not significantly different than that of the EHS group (P >0.05). ConclusionPink1/Parkin-mediated mitophagy dysfunction is one of the mechanisms underlying ALI in rats with EHS, and activation of Parkin overexpression-mediated mitophagy can alleviate ALI caused by EHS.

Protection of Parkin over-expression on lung in rats with exertional heat stroke by activating mitophagy

ObjectiveTo investigate the role of Parkin overexpression-induecd mitophagy in alleviating acute lung injury of exertional heat stroke(EHS) rats.MethodsEighty SD rats were divided into four groups: Control group (CON group), Control Parkin overexpression group (CON + Parkin group), exertional heat stroke group (EHS group), and exertional heat stroke Parkin overexpression group (EHS + Parkin group). Adeno-associated virus carrying the Parkin gene was intravenously injected into the rats to overexpress Parkin in the lung tissue. An exertional heat stroke rat model was established, and survival curves were plotted. Lung Micro-CT was performed, and lung coefficient and pulmonary microvascular permeability were measured. Enzyme-linked immunosorbent assays(ELISA) were used to determine the levels of interleukin-6(IL-6), interleukin-1β(IL-1β), Tumor necrosis factor-α(TNF-α), and reactive oxygen species(ROS). The morphology of mitochondria in type II epithelial cells of lung tissue was observed using transmission electron microscopy. The apoptosis of lung tissue, the level of mitophagy, and the co-localization of Pink1 and Parkin were determined using immunofluorescence. The expression of Pink1, Parkin, MFN2, PTEN-L, PTEN, p62, and microtubule associated protein 1 light chain 3 (LC3) in rat lung tissue was measured by western blot.ResultsCompared with the CON group, there were more severe lung injury and more higher levels of IL-6, IL-1β, TNF-α in EHS rats. Both of the LC3-II/LC3-I ratio and the co-localization of LC3 and Tom20 in the lung tissue of EHS rats decreased. Compared with the EHS group, the survival rate of rats in the EHS + Parkin overexpression group was significantly increased, lung coefficient and pulmonary microvascular permeability were reduced, and pathological changes such as exudation and consolidation were significantly alleviated. The levels of IL-6, IL-1β, TNF-α, and ROS were significantly decreased; the degree of mitochondrial swelling in type II alveolar epithelial cells was reduced, and no vacuolization was observed. Lung tissue apoptosis was reduced, and the colocalization fluorescence of Pink1 and Parkin, as well as LC3 and Tom20, were increased. The expression of Parkin and LC3-II/LC3-I ratio in lung tissue were both increased, while the expression of P62, Pink1, MFN2, and PTEN-L was decreased.ConclusionPink1/Parkin-mediated mitophagy dysfunction is one of the mechanisms underlying acute lung injury in rats with EHS, and activation of Parkin overexpression induced-mitophagy can alleviate acute lung injury caused by EHS.

Effect of 2-phenylethyl-beta-glucopyranoside isolated from Huaizhong No. 1 Rehmannia glutinosa on hypoxic pulmonary hypertension by regulating PI3K/Akt/m TOR/HIF-1α pathway

The study investigated the protective effect and mechanism of 2-phenylethyl-beta-glucopyranoside(Phe) from Huaizhong No.1 Rehmannia glutinosa on hypoxic pulmonary hypertension(PH), aiming to provide a theoretical basis for clinical treatment of PAH. Male C57BL/6N mice were randomly divided into normal group, model group, positive drug(bosentan, 100 mg·kg~(-1)) group, and low-and high-dose Phe groups(20 and 40 mg·kg~(-1)). Except for the normal group, all other groups were continuously subjected to model induction in a 10% hypoxic environment for 5 weeks, with oral administration for 14 days starting from the 3rd week. The cardiopulmonary function, right ventricular pressure, cough and asthma index, lung injury, cell apoptosis, oxidative stress-related indicators, immune cells, and phosphatidylinositol 3-kinase(PI3K)/protein kinase B(Akt)/mammalian target of rapamycin(mTOR)/hypoxic inducible factor 1α(HIF-1α) pathway-related proteins or mRNA levels were examined. Furthermore, hypoxia-induced pulmonary arterial smooth muscle cell(PASMC) were used to further explore the mechanism of Phe intervention in PH combined with PI3K ago-nist(740Y-P). The results showed that Phe significantly improved the cardiopulmonary function of mice with PH, decreased right ventricular pressure, cough and asthma index, and lung injury, reduced cell apoptosis, oxidative stress-related indicators, and nuclear levels of phosphorylated Akt(p-Akt) and phosphorylated mTOR(p-mTOR), inhibited the expression levels of HIF-1α and PI3K mRNA and proteins, and maintained the immune cell homeostasis in mice. Further mechanistic studies revealed that Phe significantly reduced the viability and migration ability of hypoxia-induced PASMC, decreased the expression of HIF-1α and PI3K proteins and nuc-lear levels of p-Akt and p-mTOR, and this effect was blocked by 740Y-P. Therefore, it is inferred that Phe may exert anti-PH effects by alleviating the imbalance of oxidative stress and apoptosis in lung tissues and regulating immune levels, and its mechanism may be related to the regulation of the PI3K/Akt/mTOR/HIF-1α pathway. This study is expected to provide drug references and research ideas for the treatment of PH.

3-methyladenine ameliorates acute lung injury by inhibiting oxidative damage and apoptosis

BackgroundAcute lung injury (ALI) is a condition characterized by inflammation and oxidative damage. 3-methyladenine (3-MA) has great potential for regulating apoptosis, but its regulatory role in ALI is unknown. MethodsLipopolysaccharide (LPS)-treated mice and tert-butyl hydroperoxide (TBHP)-treated bronchial epithelial cells were used to simulate in vivo and in vitro ALI models, respectively. In vivo, lung injury was assessed by histopathological analysis and lung injury scoring. The total cell count, protein content, and inflammatory factors in bronchoalveolar lavage fluid (BALF) were examined. The level of apoptosis in lung tissue was assessed through TUNEL staining. In the vitro ALI model, cell viability and levels of reactive oxygen species and apoptosis were assessed. Results3-MA pretreatment ameliorated lung injury, including intra-alveolar hemorrhage and inflammatory cell accumulation, both in vitro and in vivo. 3-MA pretreatment also decreased inflammatory factor levels in the BALF. 3-MA pretreatment alleviated oxidative damage, decreased reactive oxygen species levels, and attenuated morphological changes. TUNEL and Annexin V-FITC/PI staining revealed that pretreatment with 3-MA reduced the level of apoptosis. 3-MA pretreatment significantly decreased the expression of caspase-3 and Bax but increased the expression of Bcl-2 in ALI. Mechanistically, 3-MA pretreatment also affected the PKCα/NOX4 and Nrf2 pathways, which decreased the level of apoptosis in ALI. Conclusions3-MA pretreatment inhibited inflammation and oxidative damage in ALI and inhibited apoptosis to mitigate ALI in part by inhibiting the PKCα/NOX4 pathway and activating the Nrf2 pathway. Based on these results, 3-MA might be a viable medication to treat with ALI.

GOLPH3 knockdown alleviates the inflammation and apoptosis in lipopolysaccharide-induced acute lung injury by inhibiting Golgi stress mediated autophagy

Pneumonia, an acute inflammatory lesion of the lung, is the leading cause of death in children aged < 5 years. We aimed to study the function and mechanism of Golgi phosphoprotein 3 (GOLPH3) in infantile pneumonia. Lipopolysaccharide (LPS)-induced acute lung injury (ALI) mice and injury of MLE-12 cells were used as the pneumonia model in vitro. After GOLPH3 was knocked down, the histopathological changes of lung tissues were assessed by hematoxylin-eosin (H&E) staining. The Wet/Dry ratio of lung tissues was calculated. The enzyme-linked immunosorbent assay (ELISA) method was used to detecte the contents of inflammatory factors in bronchoalveolar lavage fluid (BALF). The damaged DNA in apoptotic cells in lung tissues was tested by Terminal deoxynucleotidyl transferase-mediated dUTP Nick end labeling (TUNEL) staining. Immunofluorescence staining analyzed LC3II and Golgi matrix protein 130 (GM130) expression in lung tissues and MLE-12 cells. The apoptosis of MLE-12 cells was measured by flow cytometry analysis. Additionally, the expression of proteins related to apoptosis, autophagy and Golgi stress was examined with immunoblotting. Results indicated that GOLPH3 knockdown alleviated lung tissue pathological changes in LPS-triggered ALI mice. LPS-induced inflammation and apoptosis in lung tissues and MLE-12 cells were remarkably alleviated by GOLPH3 deficiency. Besides, GOLPH3 depletion suppressed autophagy and Golgi stress in lung tissues and MLE-12 cells challenged with LPS. Moreover, Rapamycin (Rap), an autophagy inhibitor, counteracted inflammation and apoptosis inhibited by GOLPH3 silencing in LPS-induced MLE-12 cells. Furthermore, brefeldin A (BFA) pretreatment apparently abrogated the inhibitory effect of GOLPH3 knockdown on autophagy in MLE-12 cells exposed to LPS. To be concluded, GOLPH3 knockdown exerted lung protective effect against LPS-triggered inflammation and apoptosis by inhibiting Golgi stress mediated autophagy.

The Therapeutic Effect of p-Coumaric Acid on Lung Toxicity Induced by Methotrexate in Rats

The use of methotrexate (MTX), a chemotherapy agent, is limited by a number of side effects, including pulmonary toxicity. Oxidative stress (OS) and inflammation are possible mechanisms of MTX-associated pulmonary toxicity. p-Coumaric acid (PCA) is a phenolic acid that has several beneficial effects on human health, particularly antioxidant and anti-inflammatory. The potential effects of PCA in reducing MTX-induced pulmonary toxicity were investigated in the current study. After MTX (20 mg/kg) was administered to the rats on day 1, two different doses of PCA (2 and 4 mg/kg) were administered intraperitoneally for 3 days and the levels of OS, inflammation and apoptosis were assessed in the lung tissues collected on day 5. PCA applications largely eliminated MTX-induced OS, inflammation and apoptosis in lung tissue via enhancing the capacity of endogenous antioxidant system. The therapeutic effect of PCA against MTX-induced pulmonary toxicity should be re-evaluated in more systematic studies.

Effects of Maternal Smoke Exposure on Endoplasmic Reticulum Stress and Autophagy in the Lungs of Offspring Mice.

Cigarette smoke (CS) induces autophagy and endoplasmic reticulum (ER) stress in the lungs. Research suggests that maternal exposure to CS during pregnancy leads to decreased lung function in offspring. However, the effects of maternal CS exposure on lung autophagy and ER stress in offspring during pregnancy remain unclear. C57BL/6J female mice were divided into the AA (air treatment during both pre-pregnancy and pregnancy), AS (air treatment during pre-pregnancy and CS treatment during pregnancy), SA (CS treatment during pre-pregnancy and air treatment during pregnancy), and SS (CS treatment during both pre-pregnancy and pregnancy) groups. The male offspring mice were selected to the study and euthanized 49 days after birth for the study. Hematoxylin and eosin (HE) staining was employed to observe pathological alterations, while transmission electron microscopy (TEM) was utilized to examine ultrastructure and autophagic vesicles. Additionally, the terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end labeling (TUNEL) method was applied to identify apoptosis in lung tissues. Immunofluorescence, Real-Time PCR, and Western Blot analyses were conducted to assess the expression of ER stress and autophagy-related markers in lung tissues. The findings revealed that exposure to CS heightened the extent of pathological damage and the abundance of autophagosomes in the lungs of offspring mice. TUNEL results indicated an increased fluorescence intensity in the AS, SA and SS groups, with the most significant in AS and SS groups. Furthermore, CS exposure augmented the fluorescence intensity and expression of ER stress and autophagy-related proteins. The expression of C/EBP-homologous protein (CHOP) exhibited no discernible difference between the SA and SS groups but showed a significant increase in the AS group. Conversely, the expression levels of glucose-regulated protein 78 (GRP78), Caspase-12, Beclin-1, and microtubule-associated protein 1 light chain 3 (LC3) exhibited no significant difference between the AS and SA groups, whereas they were significantly upregulated in the SS group. Preconceptional and gestational exposure to CS heightened ER stress and autophagy in the lungs of mouse offspring. However, in mothers who smoked, withdrawal from CS during pregnancy led to a reduction in ER stress and autophagy in the lungs of their offspring.

Evidence that a Novel Chalcone Derivative, Compound 27, Acts on the Epithelium Via the PI3K/AKT/Nrf2-Keap1 Signaling Pathway, to Mitigate LPS-Induced Acute Lung Injury in Mice.

Acute lung injury (ALI) is a highly heterogeneous clinical syndrome and an important cause of mortality in critically ill patients, with limited treatment options currently available. Chalcone, an essential secondary metabolite found in edible or medicinal plants, exhibits good antioxidant activity and simple structure for easy synthesis. In our study, we synthesized a novel chalcone derivative, compound 27 (C27). We hypothesized that C27 could be a potential treatment for acute respiratory distress syndrome (ARDS). Therefore, the protective effects of C27 on lung epithelial cells during ALI and the underlying molecular mechanisms were investigated. In vivo, Intratracheal instillation of LPS (10mg/kg) was used to induce acute lung injury in mice. In vitro, the bronchial epithelial cell line (Beas-2b) was treated with 30μM tert-butyl hydroperoxide (t-BHP) to simulate oxidative stress. Our findings demonstrate that pretreatment with C27 reduces LPS-induced oxidative destruction and cellular apoptosis in lung tissues of mice. Furthermore, it significantly attenuates t-BHP-induced cellular reactive oxygen species (ROS) generation, mitochondrial damage, and apoptosis in vitro. Mechanistically, the signaling pathway involving Nrf2-Keap1 and the downstream antioxidative proteins were activated by C27 in vivo. Additionally, PI3K inhibitor LY294002 and Nrf2 inhibitor ML385 abolished the effect of C27 in vitro, indicating that the protective effect of C27 is mediated via the PI3K/AKT/Nrf2-Keap1 pathway. Our study provides evidence that C27 protects against LPS-induced ALI by mitigating oxidative stress via activation of the PI3K/AKT/Nrf2-Keap1 signaling pathway. Therefore, we hypothesize that C27 represents a viable alternative for ALI therapy.

Activation of Pink1/Parkin-mediated mitochondrial autophagy alleviates exertional heat stroke-induced acute lung injury in rats.

To investigate the role of Pink1/Parkin-mediated mitochondrial autophagy in exertional heat stroke-induced acute lung injury in rats. Sixty SD rats were divided into four groups: normal group (CON group), normal Parkin overexpression group (CON + Parkin group), exertional heat stroke group (EHS group), and exertional heat stroke Parkin overexpression group (EHS + Parkin group). Adeno-associated virus carrying the Parkin gene was intravenously injected into the rats to overexpress Parkin in the lung tissue. An exertional heat stroke rat model was established, and survival curves were plotted. Lung micro-CT was performed, and lung coefficient and pulmonary microvascular permeability were measured. Compared with the EHS group, the survival rate of rats in the EHS + Parkin overexpression group was significantly increased, lung coefficient and pulmonary microvascular permeability were reduced, and pathological changes such as exudation and consolidation were significantly reduced. The levels of inflammatory factors IL-6, IL-1β, TNF- α, and ROS were significantly decreased; the degree of mitochondrial swelling in type II alveolar epithelial cells was reduced, and no vacuolization was observed. Lung tissue apoptosis was reduced, and the colocalization fluorescence of Pink1 and Parkin, as well as LC3 and Tom20, were increased. The expression of Parkin and LC3-II/LC3-I ratio in lung tissue were both increased, while the expression of P62, Pink1, MFN2, and PTEN-L was decreased. Impairment of Pink1/Parkin-mediated mitochondrial autophagy function is one of the mechanisms of exertional heat stroke-induced acute lung injury in rats. Activation of the Pink1/Parkin pathway can alleviate acute lung injury caused by exertional heat stroke.

Emodin alleviates intestinal ischemia/reperfusion-induced lung injury by upregulating HO-1 expression via PI3K/AkT pathway

BackgroundEmodin, a natural anthraquinone derivative found in various Chinese medicinal herbs, has been proved to be an effective therapeutic agent in the treatment of many diseases. However, its effect on lung injury after intestinal ischemia/reperfusion injury remains unknown. This research was designed to investigate whether emodin protects against intestinal ischemia/reperfusion-induced lung injury and to elucidate the underlying molecular mechanisms in vivo and in vitro. MethodsIntestinal ischemia/reperfusion injury was induced by occluding the superior mesenteric artery in mice, and mouse lung epithelial-12 cells were subjected to oxygen-glucose deprivation and reoxygenation to establish an in vitro model. ResultsOur data indicated that emodin treatment reduced intestinal ischemia/reperfusion-induced oxidative stress, inflammation and apoptosis in lung tissues and alleviated lung injury. However, the protective effects of emodin on intestinal ischemia/reperfusion-induced lung injury were reversed by the protein kinase B inhibitor triciribine or the heme oxygenase-1 inhibitor tin protoporphyrin IX. The protein kinase inhibitor triciribine also downregulated the expression of heme oxygenase-1. ConclusionIn conclusion, our data suggest that emodin treatment protects against intestinal ischemia/reperfusion-induced lung injury by enhancing heme oxygenase-1 expression via activation of the PI3K/protein kinase pathway. Emodin may act as a potential therapeutic agent for the prevention and treatment of lung injury induced by intestinal ischemia/reperfusion.

Differences in Airway Remodeling and Emphysematous Lesions between Rats Exposed to Smoke from New-Type and Conventional Tobacco Varieties.

Genes from Perilla frutescens and Ocimum basilicum were introduced into N. tabacum L. var. HHY via distant hybridization, and the new-type tobacco varieties "Zisu" and "Luole" were developed, with noticeable differences in chemical composition. Smoking is the leading cause of chronic obstructive pulmonary disease (COPD), and its pathogenesis is complex. In the present study, 48 male Sprague-Dawley (SD) rats were randomly divided into four groups, namely, the control, "HHY", "Zisu" and "Luole", and then exposed to fresh air/cigarette smoke (CS) for 30 days and 60 days. The COPD model was constructed, and their health hazards were compared and evaluated. CS from different tobacco varieties influenced rats in varying degrees at the tissue, cell and molecular levels. The rats in the "HHY" group showed obvious symptoms, such as cough and dyspnea, which were less severe in the "Zisu" and "Luole" groups. Pathological and morphological analyses, including scores, MLI, MAN, WAt/Pbm and WAm/Pbm, showed that "Zisu" and "Luole" caused less damage to the airways and lung parenchyma than "HHY". Significant increases in the numbers of total leukocytes and neutrophils in the BALF were found in "HHY" compared to those in "Zisu" and "Luole". Moreover, they caused less oxidative stress and apoptosis in lung tissues, as reflected by indicators such as ROS, MDA, T-AOC, GSH, the apoptotic index and the ratio of Bcl-2 to Bax. "Zisu" and "Luole" even altered the ratios of MMP-9/TIMP-1 and IFN-γ/IL-4 in lung tissues to a lesser degree. These differences between CS-exposed rats may be closely related to the altered expression of Nrf2, p38 MAPK and p-p38 MAPK. Changes in chemical composition via introducing genes from some medicinal plants may be an attractive strategy for tobacco harm reduction.

Fortunellin ameliorates LPS-induced acute lung injury, inflammation, and collagen deposition by restraining the TLR4/NF-κB/NLRP3 pathway.

Acute lung injury (ALI) is the prevalent respiratory disease of acute inflammation with high morbidity and mortality. Fortunellin has anti-inflammation property, but its role in ALI remains elusive. Thus, this study clarified the function of fortunellin on ALI pathogenesis. The ALI mouse model was established by lipopolysaccharide (LPS) induction, and lung tissue damage was evaluated utilizing hematoxylin-eosin (HE) staining. The edema of lung tissue was measured by the lung wet/dry (W/D) ratio. The lung capillary permeability was reflected by the protein content in bronchoalveolar lavage fluid (BALF). Inflammatory cell infiltration was measured by the evaluation of the content of myeloperoxidase (MPO), neutrophils, and leukocytes in BALF. Cell apoptosis was measured by terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) assay. The secretions of inflammatory cytokines were quantified using enzyme-linked immunosorbent assay (ELISA) assays. Lung tissue collagen deposition was evaluated by Masson staining. Fortunellin attenuated LPS-induced lung tissue damage and reduced the W/D ratio, the content of MPO in lung tissue, the total protein contents in BALF, and the neutrophils and leukocytes number. Besides, fortunellin alleviated LPS-stimulated lung tissue apoptosis, inflammatory response, and collagen deposition. Furthermore, Fortunellin repressed the activity of the Toll-like receptor 4 (TLR4)/nuclear factor kappa-B (NF-κB)/NLR Family Pyrin Domain Containing 3 (NLRP3) pathway in the LPS-stimulated ALI model and LPS-induced RAW264.7 cells. Moreover, fortunellin attenuated LPS-stimulated tissue injury, apoptosis, inflammation, and collagen deposition of the lung via restraining the TLR4/NF-κB/NLRP3 pathway. Fortunellin attenuated LPS-stimulated ALI through repressing the TLR4/NF-κB/NLRP3 pathway. Fortunellin may be a valuable drug for ALI therapy.

Urolithin A exerts a protective effect on lipopolysaccharide-induced acute lung injury by regulating HMGB1-mediated MAPK and NF-κB signaling pathways.

Acute lung injury (ALI) is a severe inflammatory disorder that has a high morbidity and mortality rate. Urolithin A (UA) is reported to have anti-inflammatory and anti-oxidative effects in ALI. However, its molecular mechanisms in ALI remain to be explored. Mice and BEAS-2B cells were administrated with lipopolysaccharide (LPS) to mimic the ALI model in vivo and in vitro. Hematoxylin-eosin (HE) staining was used to detect the pathological injury of lung tissues. The levels of proinflammatory cytokines in bronchoalveolar lavage fluid (BALF) and culture supernatant and the levels of oxidative stress markers in lung tissues were measured using ELISA. DCFH-DA probe was used to assess the reactive oxygen species (ROS) level. TUNEL staining and flow cytometry were performed to determine cell apoptosis. The key targets and pathways were confirmed by immunohistochemistry (IHC) and western blot. UA suppressed the pathologic damage, wet/dry weight ratio, and total protein and inflammatory cells in BALF. UA decreased neutrophil infiltration and proinflammatory cytokines production. UA reduced the level of malondialdehyde (MDA) and increased the activities of superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) in pulmonary tissues. UA also inhibited cell apoptosis in lung tissues by decreasing Bax expression and increasing Bcl-2 expression. In addition, UA suppressed LPS-induced inflammatory factor production, ROS level, and cell apoptosis in BEAS-2B. Importantly, UA decreased the expression of HMGB1 in LPS-treated mice and BEAS-2B cells. HMGB1 overexpression greatly abrogated the inhibition of UA on inflammation, ROS, and cell apoptosis in LPS-administrated BEAS-2B. Furthermore, UA treatment suppressed the phosphorylated levels of p38, JNK, ERK, and p65 in LPS-administrated mice and BEAS-2B cells. UA alleviated lung inflammation, oxidative stress, and apoptosis in ALI by targeting HMGB1 to inactivate the MAPK/NF-κB signaling, suggesting the potential of UA to treat ALI.

PU.1 alleviates the inhibitory effects of cigarette smoke on endothelial progenitor cell function and lung-homing through Wnt/β-catenin and CXCL12/CXCR4 pathways.

Endothelial progenitor cells (EPCs) dysfunction is involved in the pathogenesis of chronic obstructive pulmonary disease (COPD). The transcription factor PU.1 is essential for the maintenance of stem/progenitor cell homeostasis. However, the role of PU.1 in COPD and its effects on EPC function and lung-homing, remain unclear. This study aimed to explore the protective activity of PU.1 and the underlying mechanisms in a cigarette smoke extract (CSE)-induced emphysema mouse model. C57BL/6 mice were treated with CSE to establish a murine emphysema model and injected with overexpressed PU.1 or negative control adeno-associated virus. Morphometry of lung slides, lung function, and apoptosis of lung tissues were evaluated. Immunofluorescence co-localization was used to analyze EPCs homing into the lung. Flow cytometry was performed to detect EPC count in lung tissues and bone marrow (BM). The angiogenic ability of BM-derived EPCs cultured in vitro was examined by tube formation assay. We determined the expression levels of PU.1, β-catenin, C-X-C motif ligand 12 (CXCL12), C-X-C motif receptor 4 (CXCR4), stem cell antigen-1 (Sca-1), and stemness genes. CSE exposure significantly reduced the expression of PU.1 in mouse lung tissues, BM, and BM-derived EPCs. PU.1 overexpression attenuated CSE-induced emphysematous changes, lung function decline, and apoptosis. In emphysematous mice, PU.1 overexpression markedly reversed the decreased proportion of EPCs in BM and promoted the lung-homing of EPCs. The impaired angiogenic ability of BM-derived EPCs induced by CSE could be restored by the overexpression of PU.1. In addition, PU.1 upregulation evidently reversed the decreased expression of β-catenin, CXCL12, CXCR4, Scal-1, and stemness genes in mouse lung tissues, BM, and BM-derived EPCs after CSE exposure. PU.1 alleviates the inhibitory effects of CSE on EPC function and lung-homing via activating the canonical Wnt/β-catenin pathway and CXCL12/CXCR4 axis. While further research is needed, our research may indicate a potential therapeutic target for COPD patients.

Mechanism of isorhynchophylline in lipopolysaccharide-induced acute lung injury based on proteomic technology.

Isorhynchophylline (IRN), a tetracyclic indole alkaloid, has anti-inflammatory and antioxidant activities against cardiovascular diseases and central nervous system disorders. Acute lung injury (ALI) is a manifestation of inflammation concentrated in the lungs and has a high incidence rate and mortality The purpose of this study is to explain the mechanism of IRN in the treatment of acute lung injury and to provide a new scheme for clinical treatment. The experimental mice were divided into three groups: CTRL, LPS, LPS+IRN. The mouse model of ALI was established by inhaling LPS solution through nose. After continuous administration of IRN solution for 7 days, the mice in LPS+IRN group were killed and the lung tissue was collected for detection. Proteomic (Data are available via ProteomeXchange with identifier PXD050432) results showed that 5727 proteins were detected in mouse lung tissues, and 16 proteins were screened out. IRN could reverse the trend of these differential proteins. In addition, IRN can act on integrin αM to reduce neutrophil recruitment and thereby produce anti-inflammatory effects and may suppress neutrophil migration through the leukocyte transendothelial migration pathway. TUNEL and RT-PCR experiments revealed that LPS-induced ALI in mice increases the apoptosis of lung tissues, damage to alveolar epithelial cells and levels of inflammatory factors. Treatment with IRN can repair tissues, improve lung tissue pathology and reduce lung inflammation.

Ginkgo biloba Extract 50 (GBE50) Exerts Antifibrotic and Antioxidant Effects on Pulmonary Fibrosis in Mice by Regulating Nrf2 and TGF-β1/Smad Pathways.

Pulmonary fibrosis (PF) is a progressive lung disorder with a poor prognosis. GBE50 is a new standardized Ginkgo biloba extract that has been widely used in cardiovascular diseases. However, the protective mechanism of GBE50 against PF remains to be elucidated. C57BL/6J mice were treated with bleomycin (Bleo) to induce PF in the presence or absence of GBE50. Protein content in bronchoalveolar lavage fluid (BALF) and wet weight/dry weight ratio were examined for analysis of pulmonary edema. Hematoxylin-eosin staining and Masson trichrome staining were used for histopathological observation of murine lung tissues. Ashcroft score was used for semi-quantitation of lung fibrosis degree. RT-qPCR was utilized for assessing mRNA levels of pro-fibrotic mediators in lung tissues. TUNEL staining was implemented for cell apoptosis assessment. The levels of oxidative stress- and inflammation-related markers were evaluated by corresponding commercial assay kits. Western blotting was used to evaluate levels of nuclear factor erythroid 2-related factor 2 (Nrf2) signaling- and transforming growth factor (TGF)-β1/SMAD signaling-related proteins. GBE50 alleviated lung injury and severity of fibrosis, reduced collagen deposition and cell apoptosis in lung tissues, and suppressed inflammatory response and oxidative stress injury in Bleo-stimulated PF mice. GBE50 activated Nrf2 signaling pathway and inactivated TGF-β1/SMAD signaling pathway in the lungs of Bleo-induced PF mice. Inhibition of Nrf2 signaling reversed GBE50-mediated inactivation of TGF-β1/SMAD signaling and attenuation of inflammation and oxidative stress in Bleo-induced PF mice. GBE50 protects against Bleo-induced PF in mice by mitigating fibrosis, inflammation and oxidative stress via Nrf2 and TGF-β1/SMAD signaling pathways.

Songorine inhibits oxidative stress-related inflammation through PI3K/AKT/NRF2 signaling pathway to alleviate lipopolysaccharide-induced septic acute lung injury

Objective The present study aimed to investigate the protective action and mechanism of songorine on sepsis-induced acute lung injury (ALI). Methods The sepsis-induced ALI mouse and cell models were established by lipopolysaccharide (LPS) induction. Lung injury was assayed by hematoxylin and eosin staining, lung injury score, and lung wet-to-dry (W/D) weight ratio. Apoptosis in lung tissues was evaluated by TUNEL assay, and the expression of apoptosis-related markers (Bcl2, Bax, and caspase-3) was measured by western blotting. Levels of pro-inflammatory factors and oxidative stress markers in the bronchoalveolar lavage fluid (BALF) of mice were measured by ELISA and RT-qPCR. The expression of PI3K/AKT/NRF2 pathway-related proteins was analyzed by western blotting. Results Songorine treatment at 40 mg/kg mitigated sepsis-induced ALI, characterized by improved histopathology, lung injury score, and lung W/D weight ratio (p < 0.05). Moreover, songorine markedly attenuated sepsis-induced apoptosis in lung tissues; this was evidenced by an increase in Bcl2 levels and a decrease in Bax and caspase-3 levels (p < 0.01). Also, songorine reduced levels of proinflammatory cytokines (TNF-α, IL-6, IL-1β and MPO) and oxidative stress regulators (SOD and GSH) in the BALF of LPS-induced sepsis mice and RAW264.7 cells (p < 0.05). In addition, songorine upregulated the PI3K/AKT/NRF2 pathway-related proteins in LPS-induced sepsis mice and RAW264.7 cells (p < 0.05). Furthermore, LY294002 (a PI3K inhibitor) treatment reversed the protective effect of songorine on sepsis-induced ALI. Conclusion Songorine inhibits oxidative stress-related inflammation in sepsis-induced ALI via the activation of the PI3K/AKT/NRF2 signaling pathway.

Inhibition of S100A9 alleviates neurogenic pulmonary edema after subarachnoid hemorrhage

Background and PurposeNeurogenic pulmonary edema (NPE) frequently arises as a complication subsequent to subarachnoid hemorrhage (SAH). Heterodimers of S100A8 and S100A9 are commonly formed, thereby initiating an inflammatory reaction through receptor binding on the cell surface. Paquinimod serves as a specific inhibitor of S100A9. The objective of this investigation is to assess the impact of Paquinimod administration and S100A9 knockout on NPE following SAH. MethodsIn this study, SAH models of C57BL/6J wild-type (WT) and S100A9 knockout mice were established through intravascular perforation. These models were then divided into several groups, including the WT-sham group, S100A9-KO-sham group, WT-SAH group, WT-SAH + Paquinimod group, and S100A9-KO-SAH group. After 24 h of SAH induction, pulmonary edema was assessed using the lung wet-dry weight method and Hematoxylin and eosin (HE) staining. Additionally, the expression levels of various proteins, such as interleukin-1β (IL-1β), tumor necrosis factor α (TNF-α), occludin, claudin-3, Bax, Bcl-2, TLR4, MYD88, and pNF-κB, in lung tissue were analyzed using western blot and immunofluorescence staining. Lung tissue apoptosis was detected by TUNEL staining. ResultsFirstly, our findings indicate that the knockout of S100A9 has a protective effect on early brain injury following subarachnoid hemorrhage (SAH). Additionally, the reduction of brain injury after SAH can also alleviate neurogenic pulmonary edema (NPE). Immunofluorescence staining and western blot analysis revealed that compared to SAH mice with wild-type S100A9 expression (WT-SAH), the lungs of S100A9 knockout SAH mice (S100A9-KO-SAH) and mice treated with Paquinimod exhibited decreased levels of inflammatory molecules (IL-1β and TNF-α) and increased levels of tight junction proteins. Furthermore, the knockout of S100A9 resulted in upregulated expression of the apoptotic-associated protein Bax and down-regulated expression of Bcl-2. Furthermore, a decrease in TLR4, MYD88, and phosphorylated pNF-κB was noted in S100A9-KO-SAH and Paquinimod treated mice, indicating the potential involvement of the TLR4/MYD88/NF-κB signaling pathway in the inhibition of the protective effect of S100A9 on NPE following SAH. ConclusionThe knockout of S100A9 not only ameliorated initial cerebral injury following subarachnoid hemorrhage (SAH), but also mitigated SAH-associated neurogenic pulmonary edema (NPE). Additionally, Paquinimod was found to diminish NPE. These findings imply a correlation between the central nervous system and peripheral organs, highlighting the potential of safeguarding the brain to mitigate harm to peripheral organs.