Lung Injury In Rats Research Articles

Aerosol Delivery of a Novel Recombinant Modified Superoxide Dismutase Protein Reduces Oxidant Injury and Attenuates Escherichia coli Induced Lung Injury in Rats.

Background: Acute respiratory distress syndrome (ARDS) is a life-threatening respiratory failure syndrome with diverse etiologies characterized by increased permeability of alveolar-capillary membranes, pulmonary edema, and acute onset hypoxemia. During the ARDS acute phase, neutrophil infiltration into the alveolar space results in uncontrolled release of reactive oxygen species (ROS) and proteases, overwhelming antioxidant defenses and causing alveolar epithelial and lung endothelial injury. Objectives: To investigate the therapeutic potential of a novel recombinant human Cu-Zn-superoxide dismutase (SOD) fusion protein in protecting against ROS injury and for aerosolized SOD delivery to treat Escherichia coli induced ARDS. Methods: Fusion proteins incorporating human Cu-Zn-SOD (hSOD1), with (pep1-hSOD1-his) and without (hSOD1-his) a fused hyaluronic acid-binding peptide, were expressed in E. coli. Purified proteins were evaluated in in vitro assays with human bronchial epithelial cells and through aerosolized delivery to the lung of an E. coli-induced ARDS rat model. Results: SOD proteins exhibited high SOD activity in vitro and protected bronchial epithelial cells from oxidative damage. hSOD1-his and pep1-hSOD1-his retained SOD activity postnebulization and exhibited no adverse effects in the rat. Pep1-hSOD1-his administered through instillation or nebulization to the lung of an E. coli-induced pneumonia rat improved arterial oxygenation and lactate levels compared to vehicle after 48 hours. Static lung compliance was improved when the pep1-hSOD1-his protein was delivered by instillation. White cell infiltration to the lung was significantly reduced by aerosolized delivery of protein, and reduction of cytokine-induced neutrophil chemoattractant-1, interferon-gamma, and interleukin 6 pro-inflammatory cytokine concentrations in bronchoalveolar lavage was observed. Conclusions: Aerosol delivery of a novel recombinant modified SOD protein reduces oxidant injury and attenuates E. coli induced lung injury in rats. The results provide a strong basis for further investigation of the therapeutic potential of hSOD1 in the treatment of ARDS.

Efficiency of exogenous surfactant combined with intravenous N-acetylcysteine in two-hit rodent model of ARDS

Accumulation of reactive oxygen species during hyperoxia together with secondary bacteria-induced inflammation leads to lung damage in ventilated critically ill patients. Antioxidant N-acetylcysteine (NAC) in combination with surfactant may improve lung function. We compared the efficacy of NAC combined with surfactant in the double-hit model of lung injury. Bacterial lipopolysaccharide (LPS) instilled intratracheally and hyperoxia were used to induce lung injury in Wistar rats. Animals were mechanically ventilated and treated intravenously with NAC alone or in combination with intratracheal surfactant (poractant alfa; PSUR+NAC). Control received saline. Lung functions, inflammatory markers, oxidative damage, total white blood cell (WBC) count and lung oedema were evaluated during 4 hrs. Administration of NAC increased total antioxidant capacity (TAC) and decreased IL-6. This effect was potentiated by the combined administration of surfactant and NAC. In addition, PSUR+NAC reduced the levels of TNFα, IL-1ß, and TAC compared to NAC only and improved lung injury score. The combination of exogenous surfactant with NAC suppresses lung inflammation and oxidative stress in the experimental double-hit model of lung injury.

Anti-inflammatory and antioxidative effects of dexpanthenol on nicotine-induced lung injury in rats

Anti-inflammatory and antioxidative effects of dexpanthenol on nicotine-induced lung injury in rats

Comparison of preventive and therapeutic effects of continuous exercise on acute lung injury induced with methotrexate.

Methotrexate (Mtx) is used to treat various diseases, including cancer, arthritis and other rheumatic diseases. However, it induces oxidative stress and pulmonary inflammation by stimulating production of reactive oxygen species and cytokines. Considering the positive effects of physical activity, our goal was to investigate the preventive and therapeutic role of continuous training (CT) on Mtx-induced lung injury in rats. The rats were divided into five groups of 14 animals: a control group (C); a continuous exercise training group (CT; healthy rats that experienced CT); an acute lung injury with Mtx group (ALI); a pretreatment group with CT (the rats experienced CT before ALI induction), and a post-treatment group with CT (the rats experienced CT after ALI induction). One dose of 20mg/kg Mtx intraperitoneal was administered in the Mtx and training groups. Forty-eight hours after the last exercise session all rats were sacrificed. According to our results, the levels of tumour necrosis factor-α (TNF-α), malondialdehyde (MDA), myeloperoxidase (MPO), GATA binding protein 3 (GATA3) and caspase-3 in the ALI group significantly increased compared to the control group, and the levels of superoxide dismutase (SOD), glutathione peroxidase (GPX), total antioxidant capacity (TAC), interleukin-10 (IL-10), forkhead box protein 3 (FOXP3), and T-bet decreased. In contrast, compared to the acute lung injury group, pretreatment and treatment with CT reduced TNF-α, MDA, MPO, GATA3 and caspase-3 and increased SOD, GPX, TAC, IL-10, FOXP3 and T-bet levels. The effects of CT pretreatment were more significant than the effects of CT post-treatment. Continuous exercise training effectively reduced oxidative stress and inflammatory cytokines and ameliorated Mtx-induced injury, and the effects of CT pretreatment were more significant than the effects of CT post-treatment. NEW FINDINGS: What is the central question of this study? Considering the high prevalence of lung injury in society, does exercise as a non-pharmacological intervention have ameliorating effects on lung injury? What is the main finding and its importance? Exercise can have healing effects on the lung after pulmonary injury through reducing inflammation, oxidative stress and apoptosis. Considering the lower side effects of exercise compared to drug treatments, the results of this study may be useful in the future.

Focus on the anti-inflammatory effect of glucocorticosteroids in experimental acute lung injury

AIM: Assessment of the effect of various doses of dexamethasone as an inflammation modulator in experimental lipopolysaccharide-induced acute lung injury in rats.
 MATERIALS AND METHODS: Acute lung injury in rats was modeled by intratracheal administration of cell wall lipopolysaccharide from the Salmonella enterica. White male rats were divided into groups: a group of intact animals (n = 10); the control group (n = 40), in which the animals were simulated acute lung injury without further treatment and removed from the experiment on day 3; three experimental groups (n = 40), in which, 3 hours after modeling acute lung injury, and then daily once a day for 3 days, dexamethasone solution was administered intraperitoneally in the following doses: in group 1 0.52 mg/kg (equivalent to 6.0 mg/day for a person), in group 2 1.71 mg/kg (20.0 mg/day for a person), in group 3 8.0 mg/kg (94.0 mg/day, pulse therapy for humans). On the 3rd day, blood samples were taken from the caudal vena cava in surviving animals for clinical analysis and evaluation of the function of mitochondria of peripheral blood leukocytes. To determine the severity of local inflammatory reactions and pulmonary edema, bronchoalveolar lavage was performed with the study of an endopulmonary cytogram and an assessment of pathomorphological changes in the lung tissue.
 RESULTS: indicate that dexamethasone reduces the amount of lung tissue damage and animal mortality, dose-dependently reduces the functions of mitochondria and the number of lymphocytes and monocytes in peripheral blood, as well as neutrophils, lymphocytes and macrophages in bronchoalveolar lavage samples.
 CONCLUSION: The use of dexamethasone at a dose of 0.52 mg/kg (equivalent to 6.0 mg/day for humans) is accompanied by better survival, minimal effect on the viability and functional activity of inflammatory cells. Pulse therapy leads to a significant decrease in the number of immunocompetent cells in bronchoalveolar lavage, mitochondrial dysfunction in the form of a decrease in the ability of these cells to use the reserve power of mitochondrial respiration in response to the action of a stress factor. Excessive inhibition of immunocompetent cells can contribute to the activation of latent and opportunistic infections, which must be taken into account when choosing a dosing regimen for glucocorticosteroids.

Proteomics analysis of lung tissue reveals protein makers for the lung injury of adjuvant arthritis rats.

Lung injury is one of the common extra‑articular lesions in rheumatoid arthritis (RA). Due to its insidious onset and no obvious clinical symptoms, it can be easily dismissed in the early stage of diagnosis, which is one of the reasons that leads to a decline of the quality of life and subsequent death of patients with RA. However, its pathogenesis is still unclear and there is a lack of effective therapeutic targets. In the present study, tandem mass tag‑labeled proteomics was used to research the lung tissue proteins in RA model (adjuvant arthritis, AA) rats that had secondary lung injury. The aim of the present study was to identify the differentially expressed proteins related to RA‑lung injury, determine their potential role in the pathogenesis of RA‑lung injury and provide potential targets for clinical treatment. Lung tissue samples were collected from AA‑lung injury and normal rats. The differentially expressed proteins (DEPs) were identified by tandem mass spectrometry. Bioinformatic analysis was used to assess the biological processes and signaling pathways associated with these DEPs. A total of 310 DEPs were found, of which 244 were upregulated and 66 were downregulated. KEGG anlysis showed that 'fatty acid degradation', 'fatty acid metabolism', 'fatty acid elongation', 'complement and coagulation cascades', 'peroxisome proliferator‑activated receptor signaling pathway' and 'hypoxia‑inducible factor signaling pathway' were significantly upregulated in the lung tissues of AA‑lung injury. Immunofluorescence staining confirmed the increased expression of clusterin, serine protease inhibitors and complement 1qc in lung tissue of rats with AA lung injury. In the present study, the results revealed the significance of certain DEPs (for example, C9, C1qc and Clu) in the occurrence and development of RA‑lung injury and provided support through experiments to identify potential biomarkers for the early diagnosis and prevention of RA‑lung injury.

Evaluation of the Protective Effect of Citral, Silymarin, and Thymoquinone on Methotrexate-Induced Lung Injury in Rats.

Several studies have reported that methotrexate is an anti-cancer and immunosuppressive drug leading to lung injury. Therefore, the present study aimed to investigate the protective effects of silymarin, citral, and thymoquinone on methotrexate-induced pulmonary toxicity. Forty-eight rats were divided into six groups, including healthy, Methotrexate, and drug carrier control groups and silymarin, citral, and thymoquinone treatment groups. At the end of the experiment, the studied rats were anesthetized and sacrificed by CO2. Lung tissue samples were isolated to measure the antioxidant activity and histopathological evaluation. In the thymoquinone treatment group, the concentration of total antioxidant capacity and Malondialdehyde increased and decreased significantly, respectively, compared to the methotrexate group. The histopathological evaluation of the lung of the methotrexate group showed hemorrhage and congestion, the nodule-like accumulation of mononuclear inflammatory lymphocytes around the blood vessel, a small number of neutrophils around the blood vessel, and the inflammatory cells around the small vessels. However, no significant pathological alterations were observed in the treatment groups, especially the thymoquinone treatment group. Thymoquinone has the greatest protective effect on methotrexate-induced lung injury, probably due to its antioxidant effect.

Ischemia/reperfusion-activated ferroptosis in the early stage triggers excessive inflammation to aggregate lung injury in rats.

Lung ischemia/reperfusion injury (LIRI) is a clinical syndrome of acute lung injury that occurs after lung transplantation or remote organ ischemia. Ferroptosis and inflammation are involved in the pathogenesis of LIRI according to the results of several studies on animal models. However, the interactive mechanisms between ferroptosis and inflammation contributing to LIRI remain unclear. HE staining and indicators of oxidative stress were used to evaluated the lung injury. The reactive oxygen species (ROS) level was examined by DHE staining. The quantitative Real-time PCR (qRT-PCR) and western blot analysis were employed to detect the level of inflammation and ferroptosis, and deferoxamine (DFO) was used to assess the importance of ferroptosis in LIRI and its effect on inflammation. In the present study, the link of ferroptosis with inflammation was evaluated at reperfusion 30-, 60- and 180-minute time points, respectively. As the results at reperfusion 30-minute point shown, the pro-ferroptotic indicators, especially cyclooxygenase (COX)-2 and acyl-CoA synthetase long-chain family member 4 (ACSL4), were upregulated while the anti-ferroptotic factors glutathione peroxidase 4 (GPX4), cystine-glumate antiporter (XCT) and ferritin heavy chain (FTH1) were downregulated. Meanwhile, the increased level of interleukin (IL)-6, tumor necrosis factor alpha (TNF-α) and IL-1β were observed beginning at reperfusion 60-minute point but mostly activated at reperfusion 180-minute point. Furthermore, deferoxamine (DFO) was employed to block ferroptosis, which can alleviate lung injury. Expectedly, the survival rate of rats was increased and the lung injury was mitigated containing the improvement of type II alveolar cells ultrastructure and ROS production. In addition, at the reperfusion 180-minute point, the inflammation was observed to be dramatically inhibited after DFO administration as verified by IL-6, TNF-α and IL-1β detection. These findings suggest that ischemia/reperfusion-activated ferroptosis plays an important role as the trigger for inflammation to further deteriorate lung damages. Inhibiting ferroptosis may have therapeutic potential for LIRI in clinical practice.

L-citrulline attenuates lipopolysaccharide-induced inflammatory lung injury in neonatal rats.

Prenatal or postnatal lung inflammation and oxidative stress disrupt alveolo-vascular development leading to bronchopulmonary dysplasia (BPD) with and without pulmonary hypertension. L-citrulline (L-CIT), a nonessential amino acid, alleviates inflammatory and hyperoxic lung injury in preclinical models of BPD. L-CIT modulates signaling pathways mediating inflammation, oxidative stress, and mitochondrial biogenesis-processes operative in the development of BPD. We hypothesize that L-CIT will attenuate lipopolysaccharide (LPS)-induced inflammation and oxidative stress in our rat model of neonatal lung injury. Newborn rats during the saccular stage of lung development were used to investigate the effect of L-CIT on LPS-induced lung histopathology and pathways involved in inflammatory, antioxidativeprocesses, and mitochondrial biogenesis in lungs in vivo, and in primary culture of pulmonary artery smooth muscle cells, in vitro. L-CIT protected the newborn rat lung from LPS-induced: lung histopathology, ROS production, NFκB nuclear translocation, and upregulation of gene and protein expression of inflammatory cytokines (IL-1β, IL-8, MCP-1α, and TNF-α). L-CIT maintained mitochondrial morphology, increased protein levels of PGC-1α, NRF1, and TFAM (transcription factors involved in mitochondrial biogenesis), and induced SIRT1, SIRT3, and superoxide dismutases protein expression. L-CIT may be efficacious in decreasing early lung inflammation and oxidative stress mitigating progression to BPD. The nonessential amino acid L-citrulline (L-CIT) mitigated lipopolysaccharide (LPS)-induced lung injury in the early stage of lung development in the newborn rat. This is the first study describing the effect of L-CIT on the signaling pathways operative in bronchopulmonary dysplasia (BPD) in a preclinical inflammatory model of newborn lung injury. If our findings translate to premature infants, L-CIT could decrease inflammation, oxidative stress and preserve mitochondrial health in the lung of premature infants at risk for BPD.

ERRα protects against sepsis-induced acute lung injury in rats

BackgroundSepsis-induced acute lung injury (ALI) is associated with poor survival rates. The identification of potential therapeutic targets for preventing sepsis-induced ALI has clinical importance. This study aims to investigate the role of estrogen-related receptor alpha (ERRα) in sepsis-induced ALI.MethodsLipopolysaccharide (LPS) was used to simulate sepsis-induced ALI model in rat pulmonary microvascular endothelial cells (PMVECs). The effects of ERRα overexpression and knockdown on LPS-induced endothelial permeability, apoptosis and autophagy were determined by horseradish peroxidase permeability assay, TdT-mediated dUTP Nick End Labeling (TUNEL) assay, flow cytometry, immunofluorescence staining, RT-PCR and Western Blotting. The rat model with sepsis-induced ALI was established by cecal ligation and puncture in anesthetized rats to verify the results of in vitro experiments. Animals were randomly assigned to receive intraperitoneal injection of vehicle or ERRα agonist. Lung vascular permeability, pathological injury, apoptosis and autophagy were examined.ResultsOverexpression of ERRα ameliorated LPS-induced endothelial hyperpermeability, degradation of adherens junctional molecules, upregulation of bax, cleaved caspase 3 and cleaved caspase 9 levels, downregulation of anti-apoptotic protein Bcl-2 level, and promoted the formation of autophagic flux, while the knockdown of ERRα exacerbated LPS-induced apoptosis and inhibited the activation of autophagy. Administration of ERRα agonist alleviated the pathological damage of lung tissue, increased the levels of tight junction proteins and adherens junction proteins, and decreased the expression of apoptosis-related proteins. Promoting the expression of ERRα significantly enhanced the process of autophagy and reduced CLP-induced ALI. Mechanistically, ERRα is essential to regulate the balance between autophagy and apoptosis to maintain the adherens junctional integrity.ConclusionERRα protects against sepsis-induced ALI through ERRα-mediated apoptosis and autophagy. Activation of ERRα provides a new therapeutic opportunity to prevent sepsis-induced ALI.

Silencing information regulator 1 ameliorates lipopolysaccharide-induced acute lung injury in rats via the upregulation of caveolin-1

BackgroundAcute lung injury (ALI) is an intractable medical problem linked with to high morbidity and mortality all over the worldglobally. The prognosis of advanced acute lung injury remains persistently poor due to its underlying mechanisms remain unclear.Despite advancements in medical research, the its prognosis of advanced ALI remains persistently poor due to unclear underlying mechanisms. We aimed to investigate the protective effects of silencing information regulator 1 (SIRT1) on lipopolysaccharide (LPS)-induced acute lung injuryALI and to reveal its underlying molecular mechanism. MethodsMale Sprague-–Dawley rats were divided grouped into 4 groupsfour: normal saline group (group NS), lipopolysaccharide group (group L), SIRT1 activator SRT1720-pretreated group (group S), and SIRT1 inhibitor EX527- pretreated group (group E). Rats They were intranasally dripped with LPS to establish the model of ALI modelsacute lung injury respectively. We investigated the effect of SIRT1 on acute lung injury by analysing We analyzed the CT images of the rat lungs and used, HE staining, lung wet-to-dry ratio, inflammatory factor expression, lung injury marker expression, immunohistochemistry, and related mRNA expression to determine the effect of SIRT1 on ALI. ResultsOur results show that LPS induction produced resulted in acute lung injury, ALI and disrupting disrupted normal SIRT1 expression, which led to the overexpression of STAT3, TLR4, TNF-ɑ, and IL-6 and suppression of Cav-1 expression. Upregulation The upregulation of Cav-1 protein and mRNA following the administration of an SIRT1 agonist resulted in reduced lung injury. SRT1720 pretreatment was closely associated with reduced expressions of STAT3,TLR4, TNF-ɑ, and IL-6. ALI lung injury was more severeworsened after administration of SIRT1 inhibitors, and the changes in the above indicators were reversed. ConclusionsThese results suggest that SIRT1 may protect against LPS-induced acute lung injuryALI via by counteracting inflammatory remissionion, and this protective effect might may be mediated by suppressing STAT3 to activate the expression ofinduce Cav-1 expression.

Protective effect of baicalin against lipopolysaccharideinduced acute lung injury in rats, and the mechanism of action

Purpose: To study the protective influence of baicalin (BA) against LPS-mediated acute lung injury (ALI) in a rat model.
 Methods: Twenty-seven Sprague-Dawley (SD) rats were assigned (9 rats each) to groups as follows: normal control (NC) treated intraperitoneally with normal saline; lipopolysaccharide (LPS) group treated with 10 mg/kg LPS; and lipopolysaccharide and baicalin (LPS + Ba) group treated with 100 mg/kg LPS, followed 15 min later by 10 mg/kg of baicalin. Pathological changes were assessed by H & E staining. Different types of cells were identified and counted using Rayleigh Giemsa staining. Levels of IL-6 and TNF-α and IL-1β in pulmonary tissue were determined by enzyme-linked immunosorbent assay (ELISA). Matute-Bello scoring method was applied to evaluate the extent of lung injury, while pulmonary expression levels of Nrf2, HO-1 and NQO1 were assayed with Western blot.
 Results: Lung injury score, and numbers of neutrophils and macrophages were significantly higher in LPS than in NC group. Inflammatory score, and numbers of neutrophils and macrophages in LPS + BA group were significantly lower than those in LPS group (p < 0.05). Compared with NC group, lung tissue levels of IL-6, TNF-α and IL-1β in LPS group were significantly increased, but were significantly reduced in LPS + BA rats, relative to LPS rats (p < 0.05). Expression levels of Nrf2, HO-1 and NQO1 in lung tissue were significantly lower in LPS group than in NC group (p < 0.05) but higher in lung tissue of LPS + BA group, relative to LPS group.
 Conclusion: Baicalin (BA) protects rats from LPS-induced ALI by enhancing the expressions of Nrf2 and HO-1 through activation of Nrf2/ARE signal pathway. These findings may be useful in developing novel BA-based anti-inflammatory drugs.

Dissecting the effects of paraquat-induced pulmonary injury in rats using UPLC-Q-TOF-MS/MS-based metabonomics.

Paraquat (PQ) is a toxic compound that selectively accumulates in the lungs, inducing severe pulmonary inflammation and fibrosis. However, data on the metabolomic changes induced by the PQ remain scant. This study aimed to determine the metabolic changes in Sprague-Dawley rats subjected to PQ using UPLC-Q-TOF-MS/MS. We established groups of PQ-induced pulmonary injury rats for 14 or 28days. Our data showed that PQ decreased the survival of the rats and induced pulmonary inflammation at day 14 or pulmonary fibrosis at day 28. There was upregulation of IL-1β expression in the inflammation group as well as upregulation of fibronectin, collagen and α-SMA in the pulmonary fibrosis group. OPLS-DA revealed differential expression of 26 metabotites between the normal and the inflammation groups; 31 plasma metabotites were also differently expressed between the normal and the fibrosis groups. There was high expression of lysoPc160-, hydroxybutyrylcarnitine, stearic acid, and imidazolelactic acid in the pulmonary injury group compared to the normal group. Metabolomics analysis confirmed that the PQ-induced lung injury was not only related to the aggravation of inflammation and apoptosis but also to mediated histidine, serine, glycerophospholipid, and lipid metabolism. This study gives insights into the mechanisms of PQ-induced lung injury and highlights the potential therapeutic targets. The effect of PQ on lung injury in rats was detected by metabonomics, and the possible metabolic mechanism was investigated by KEGG analysis. OPLS-DA revealed the differential expression of 26 metabotites and 31 plasma metabotites between the normal and the pulmonary injury groups. Metabolomics analysis confirmed that the PQ-induced lung injury was not only related to the aggravation of inflammation and apoptosis but also to mediated histidine, serine, glycerophospholipid, and lipid metabolism. Oleoylethanolamine, stearic acid, and imidazolelactic acid are potential molecular markers in PQ-induced pulmonary injury.

Cepharanthine Dry Powder Inhaler for the Treatment of Acute Lung Injury.

Severe acute respiratory syndrome Coronavirus 2 (SARS-CoV-2) induces a severe cytokine storm that may cause acute lung injury/acute respiratory distress syndrome (ALI/ARDS) with high clinical morbidity and mortality in infected individuals. Cepharanthine (CEP) is a bisbenzylisoquinoline alkaloid isolated and extracted from Stephania cepharantha Hayata. It exhibits various pharmacological effects, including antioxidant, anti-inflammatory, immunomodulatory, anti-tumor, and antiviral activities. The low oral bioavailability of CEP can be attributed to its poor water solubility. In this study, we utilized the freeze-drying method to prepare dry powder inhalers (DPI) for the treatment of acute lung injury (ALI) in rats via pulmonary administration. According to the powder properties study, the aerodynamic median diameter (Da) of the DPIs was 3.2 μm, and the in vitro lung deposition rate was 30.26; thus, meeting the Chinese Pharmacopoeia standard for pulmonary inhalation administration. We established an ALI rat model by intratracheal injection of hydrochloric acid (1.2 mL/kg, pH = 1.25). At 1 h after the model's establishment, CEP dry powder inhalers (CEP DPIs) (30 mg/kg) were sprayed into the lungs of rats with ALI via the trachea. Compared with the model group, the treatment group exhibited a reduced pulmonary edema and hemorrhage, and significantly reduced content of inflammatory factors (TNF-α, IL-6 and total protein) in their lungs (p < 0.01), indicating that the main mechanism of CEP underlying the treatment of ALI is anti-inflammation. Overall, the dry powder inhaler can deliver the drug directly to the site of the disease, increasing the intrapulmonary utilization of CEP and improving its efficacy, making it a promising inhalable formulation for the treatment of ALI.

Protective effect of melatonin and ascorbic acid combination on sepsis-induced lung injury: An Experimental study.

This study investigated the synergistic protective effects of melatonin (MEL) and ascorbic acid (vitamin C, ASA) in treating sepsis-induced lung injury in rats. Rats were divided into five groups: control, cecal ligation and puncture (CLP), CLP + MEL, CLP + ASA and CLP + MEL + ASA. The effects of MEL (10 mg/kg), ASA (100 mg/kg) and their combination on oxidative stress, inflammation and histopathology were evaluated in septic rats' lung tissues. Sepsis-induced oxidative stress and inflammation were evident through increased levels of malondialdehyde (MDA), myeloperoxidase (MPO), total oxidant status (TOS)and oxidative stress index (OSI); decreased levels of superoxide dismutase (SOD), glutathione (GSH), catalase (CAT) and glutathione peroxidase (GPx); and elevated levels of tumour necrosis factor-α (TNF-α) and interleukin-1 β (IL-1β) in the lung tissue. Treatment with MEL, ASA and their combination significantly improved antioxidant capacity and reduced oxidative stress, with the combination treatment being more effective. The combination treatment also significantly reduced TNF-α and IL-1β levels and improved peroxisome proliferator-activated receptor (PPAR), arylesterase (ARE) and paraoxonase (PON) levels in the lung tissue. Histopathological examination showed reduced oedema and lymphocyte infiltration with a lung tissue appearance similar to the control group. Immunohistochemical staining for caspase 3 demonstrated reduced immune positivity in the treatment groups. In conclusion, this study supports the potential synergistic protective effects of MEL and ASA in treating sepsis-induced lung injury. The combination therapy could effectively reduce oxidative stress, inflammation and improve antioxidant capacity in septic rats, suggesting a promising strategy for treating sepsis-induced lung injury.

Exploring the Modulatory Effect of High-Fat Nutrition on Lipopolysaccharide-Induced Acute Lung Injury in Vagotomized Rats and the Role of the Vagus Nerve.

During esophagectomy, the vagus nerve is transected, which may add to the development of postoperative complications. The vagus nerve has been shown to attenuate inflammation and can be activated by a high-fat nutrition via the release of acetylcholine. This binds to α7 nicotinic acetylcholine receptors (α7nAChR) and inhibits α7nAChR-expressing inflammatory cells. This study investigates the role of the vagus nerve and the effect of high-fat nutrition on lipopolysaccharide (LPS)-induced lung injury in rats. Firstly, 48 rats were randomized in 4 groups as follows: sham (sparing vagus nerve), abdominal (selective) vagotomy, cervical vagotomy and cervical vagotomy with an α7nAChR-agonist. Secondly, 24 rats were randomized in 3 groups as follows: sham, sham with an α7nAChR-antagonist and cervical vagotomy with an α7nAChR-antagonist. Finally, 24 rats were randomized in 3 groups as follows: fasting, high-fat nutrition before sham and high-fat nutrition before selective vagotomy. Abdominal (selective) vagotomy did not impact histopathological lung injury (LIS) compared with the control (sham) group (p > 0.999). There was a trend in aggravation of LIS after cervical vagotomy (p = 0.051), even after an α7nAChR-agonist (p = 0.090). Cervical vagotomy with an α7nAChR-antagonist aggravated lung injury (p = 0.004). Furthermore, cervical vagotomy increased macrophages in bronchoalveolar lavage (BAL) fluid and negatively impacted pulmonary function. Other inflammatory cells, TNF-α and IL-6, in the BALF and serum were unaffected. High-fat nutrition reduced LIS after sham (p = 0.012) and selective vagotomy (p = 0.002) compared to fasting. vagotomy. This study underlines the role of the vagus nerve in lung injury and shows that vagus nerve stimulation using high-fat nutrition is effective in reducing lung injury, even after selective vagotomy.

Molsidomine decreases hyperoxia-induced lung injury in neonatal rats.

The study's objective is to evaluate if Molsidomine (MOL), an anti-oxidant, anti-inflammatory, and anti-apoptotic drug, is effective in treating hyperoxic lung injury (HLI). The study consisted of four groups of neonatal rats characterized as the Control, Control+MOL, HLI, HLI + MOL groups. Near the end of the study, the lung tissue of the rats were evaluated with respect to apoptosis, histopathological damage, anti-oxidant and oxidant capacity as well as degree of inflammation. Compared to the HLI group, malondialdehyde and total oxidant status levels in lung tissue were notably reduced in the HLI + MOL group. Furthermore, mean superoxide dismutase, glutathione peroxidase, and glutathione activities/levels in lung tissue were significantly higher in the HLI + MOL group as compared to the HLI group. Tumor necrosis factor-α and interleukin-1β elevations associated with hyperoxia were significantly reduced following MOL treatment. Median histopathological damage and mean alveolar macrophage numbers were found to be higher in the HLI and HLI + MOL groups when compared to the Control and Control+MOL groups. Both values were increased in the HLI group when compared to the HLI + MOL group. Our research is the first to demonstrate that bronchopulmonary dysplasia may be prevented through the protective characteristics of MOL, an anti-inflammatory, anti-oxidant, and anti-apoptotic drug. Molsidomine prophylaxis significantly decreased the level of oxidative stress markers. Molsidomine administration restored the activities of antioxidant enzymes. Molsidomine prophylaxis significantly reduced the levels of inflammatory cytokines. Molsidomine may provide a new and promising therapy for BPD in the future. Molsidomine prophylaxis decreased lung damage and macrophage infiltration in the tissue.

Metabolomics investigation reveals metabolic mediators associated with Ligusticum wallichii-relieving experimental acute pancreatitis

Background: Acute pancreatitis (AP) is a typical destructive inflammation of the pancreas. The direct effect of L. wallichii on AP remains unknown. Methods: AP animal model was constructed by intraperitoneal injection of caerulein in male Sprague–Dawley rats. L. wallichii extracts were used to treat rats with AP. Then, tissue injury was evaluated by hematoxylin and eosin staining. Serum indicators, including amylase, lipase, KL-6, creatinine and urea, were measured by commercial kits. GC/MS-based metabolomics was utilized to characterize the metabolome. Results: Intraperitoneal injection of L. wallichii extracts protected against lung, liver, and kidney injury in rats with caerulein-induced AP. GC/MS-based metabolomics analysis revealed that L. wallichii treatment could restore caerulein-induced alteration of the abundance of most metabolites. These differential metabolites enriched twelve metabolic pathways that were able to be reprogramed by L. wallichii administration. L. wallichii impacted arginine metabolism by inhibiting arginase expression and activity. Inhibition of arginase by S-(2-boronoethyl)-L-cysteine (BEC) could relieve caerulein-induced AP, suggesting that suppression of arginase is a potential mechanism for L. wallichii to ameliorate AP. Conclusion: Our data provide the inter-relationship between metabolic reprograming and anti-AP effects of L. wallichii extracts in rats, and highlight the potential of metabolic reprograming against AP pathogenesis.

Bovine pulmonary surfactant alleviates inflammation and epithelial cell apoptosis in the early phase of lipopolysaccharide-induced acute lung injury in rats

ABSTRACT We investigate the impact of bovine pulmonary surfactant (PS) on LPS-induced ALI in vitro and in vivo to improve recognition and prevent mortality in sepsis-induced ALI. Primary alveolar type II (AT2) cells were treated with LPS alone or in combination with PS. Cell morphology observation, CCK-8 proliferation assay, flow cytometry apoptosis assay, and ELISA for inflammatory cytokine levels were performed at different time points after treatment. An LPS-induced ALI rat model was established and treated with vehicle or PS. Lung wet/dry weight ratio, histopathological changes, lung function parameters, and serum inflammatory cytokine levels were examined 6 h after PS treatment. Survival analysis by Kaplan-Meier method. RNA sequencing was conducted to identify LPS-induced differentially expressed genes in rat lungs. Proapoptotic gene expression in rat lungs was determined by Western blot. LPS significantly inhibited cell proliferation while promoting apoptosis of AT2 cells starting 2 h after treatment, accompanied by a significant increase in inflammatory cytokine production; PS reversed these effects. PS decreased the lung wet/dry ratio in septic rats, histological abnormalities, alterations in lung function parameters, and inflammatory cytokines production; while improving the overall survival of rats. LPS-induced differentially expressed genes were closely associated with apoptosis. PS attenuated LPS-induced upregulation of proapoptotic gene expression starting 2 h after treatment in AT2 cells while restoring lung ATPase activity in vivo. Bovine PS alleviates LPS-induced ALI in the early phase, possibly by suppressing inflammation and AT2 cell apoptosis, as a preemptive therapeutic agent for managing sepsis-induced ALI.

Glutamine inhibits inflammation, oxidative stress, and apoptosis and ameliorates hyperoxic lung injury.

Glutamine (Gln) is the most widely acting and abundant amino acid in the body and has anti-inflammatory properties, regulates body metabolism, and improves immune function. However, the mechanism of Gln's effect on hyperoxic lung injury in neonatal rats is unclear. Therefore, this work focused on examining Gln's function in lung injury of newborn rats mediated by hyperoxia and the underlying mechanism. We examined body mass and ratio of wet-to-dry lung tissue weights of neonatal rats. Hematoxylin and eosin (HE) staining was performed to examine histopathological alterations of lung tissues. In addition, enzyme-linked immunoassay (ELISA) was conducted to measure pro-inflammatory cytokine levels within bronchoalveolar lavage fluid (BALF). Apoptosis of lung tissues was observed using TUNEL assay. Western blotting was performed for detecting endoplasmic reticulum stress (ERS)-associated protein levels. The results showed that Gln promoted body weight gain, significantly reduced pathological damage and oxidative stress in lung tissue, and improved lung function in neonatal rats. Gln reduced pro-inflammatory cytokine release as well as inflammatory cell production in BALF and inhibited apoptosis in lung tissue cells. Furthermore, we found that Gln could downregulate ERS-associated protein levels (GRP78, Caspase-12, CHOP) and inhibit c-Jun N-terminal kinase (JNK) and inositol-requiring enzyme 1 alpha (IRE1α) phosphorylation. These results in an animal model of bronchopulmonary dysplasia (BPD) suggest that Gln may have a therapeutic effect on BPD by reducing lung inflammation, oxidative stress, and apoptosis and improving lung function; its mechanism of action may be related to the inhibition of the IRE1α/JNK pathway.