Hydroxychloroquine attenuates sepsis-induced acute respiratory distress syndrome in rats.

BACKGROUND: This study investigates the effects of hydroxychloroquine (HCQ) on a sepsis-induced acute respiratory distress syndrome (ARDS) model in rats, initiated by a fecal intraperitoneal injection procedure (FIP). METHODS: Three groups were established: control (n=8), FIP + saline (n=7), and FIP + HCQ (20 mg/kg/day) (n=9). Blood samples were collected for arterial blood gas and biochemical analyses, and bilateral pneumonectomy was performed for histopathologic examination. RESULTS: In the FIP + saline group, PaO2 decreased and PaCO2 increased, whereas these levels normalized in the FIP + HCQ group compared to the control (p<0.001 and p<0.05, respectively). Histopathological scores for alveolar congestion, perivascular/interstitial edema, hemorrhage in alveolar tissue, leukocyte infiltration or aggregation in air spaces/vascular walls, and alveolar wall/hyaline membrane thickness increased in the FIP + saline group compared to the control group (p<0.01). These scores decreased in the FIP + HCQ group compared to the FIP + saline group (p<0.01). HCQ reversed the sepsis-induced increase in malondialdehyde, tumor necrosis factor-alpha, interleukin-6, and lactic acid. CONCLUSION: HCQ may be an effective and safe option to mitigate the severe progression of ARDS.

Systemic Corticosteroid as an Adjunct for Acute Respiratory Distress Syndrome in Non-Fatal Fresh Water Drowning: An Evidence-based Case Report.

BACKGROUND: Acute lung injury or acute respiratory distress syndrome (ARDS) is one of the most common complications of non-fatal drowning. Although respiratory societies' guidelines endorse the role of systemic corticosteroids in ARDS, the evidence for systemic corticosteroid use in ARDS due to non-fatal drowning is limited. METHODS: A search was conducted on Pubmed, OVID, and EuropePMC, assessing the clinical question using inclusion and exclusion criteria. The selected studies were critically appraised, and the results were summarized. RESULTS: A total of six retrospective studies were selected and assessed, all studies showed poor validity and a high risk of bias. Out of six studies, only four informed us of steroid administration's effect on outcomes. In two studies, mortality associated with corticosteroid administration seemed to be higher. On the contrary, one study found no mortality in the corticosteroid group, but 100% mortality was observed in the control group. In another study, steroid therapy seemed to not affect hospital length of stay or mechanical ventilation rates. CONCLUSION: Corticosteroid administration for non-fatal drowning and its impact on clinical outcomes remains equivocal. Routine administration of corticosteroids is not indicated and should be done on a case-by-case basis.

Effect of caspase inhibitors on hemodynamics and inflammatory factors in ARDS model rats.

To study the effects of caspase inhibitors on hemodynamics and inflammatory factors in acute respiratory distress syndrome (ARDS) model rats. Sixty healthy male Wistar rats were randomly divided into three groups, namely, the control group, ARDS group and ARDS + Caspase inhibitor group, with 20 rats in each group. The control group was intraperitoneally injected with 2 mL/kg saline, and the ARDS model group was established by intraperitoneally injecting 4 mg/kg Lipopolysaccharide (LPS), ARDS + Caspase inhibitor group was adminstered 20 mg/kg caspase inhibitor after intraperitoneal LPS injection. Changes in pulmonary arterial pressure (PAP) and mean arterial pressure (MAP) at 6 and 12 h before and after administration were recorded. Moreover, arterial blood gas was evaluated with a blood gas analyzer and changes in the partial pressure of O2 (PaO2), partial pressure of CO2 (PaCO2), partial pressure of O2/fraction of inspired O2 (PaO2/FiO2) were evaluated. In addition, the lung wet/dry weight (W/D) ratio and inflammatory factor levels in lung tissue were determined. Finally, pathological sections were used to determine the pulmonary artery media thickness (MT), MT percentage (MT%), and the degree of muscle vascularization. The pulmonary arterial pressure of rats was determined at several time points. Compared with the control group, the model group had a significantly increased pulmonary arterial pressure at each time point (P < 0.01), and the mean arterial pressure significantly increased at 6 h (P < 0.05). Compared with that of rats in the model group, the pulmonary arterial pressure of rats in drug administration group was significantly reduced at each time point after administration (P < 0.01), and the mean arterial pressure was significantly reduced at 6 h (P < 0.05). The arterial blood gas analysis showed that compared with those in the control group, PaO2, PaCO2 and PaO2/FiO2 in the model group were significantly reduced (P < 0.01), and PaO2, PaCO2 and PaO2/FiO2 were significantly increased after caspase inhibitor treatment (P < 0.05 or 0.01). The levels of the inflammatory mediators tumor necrosis factor-alpha (TNF-α), interleukin-1ß (IL-1ß) and interleukin-6 (IL-6) in the model group were significantly higher than those in the control group (P < 0.01), and they were significantly decreased after caspase inhibitor treatment (P < 0.01). In the model group, pulmonary artery MT, MT% and the degree of muscle vascularization were significantly increased (P < 0.05 or 0.01), and pulmonary artery MT and the degree of muscle vascularization were significantly reduced after caspase inhibitor treatment (P < 0.05 or 0.01). Apoptosis Repressor with a Caspase Recuitment Domain (ARC) can alleviate the occurrence and development of pulmonary hypertension (PH) by affecting hemodynamics and reducing inflammation.

Red Blood Cell-Hitchhiking Delivery of Simvastatin to Relieve Acute Respiratory Distress Syndrome.

Purpose: The purpose of this study is to address the high mortality and poor prognosis associated with Acute Respiratory Distress Syndrome (ARDS), conditions characterized by acute and progressive respiratory failure. The primary goal was to prolong drug circulation time, increase drug accumulation in the lungs, and minimize drug-related side effects. Methods: Simvastatin (SIM) was used as the model drug in this study. Employing a red blood cell surface-loaded nanoparticle drug delivery technique, pH-responsive cationic nanoparticles loaded with SIM were non-covalently adsorbed onto the surface of red blood cells (RBC), creating a novel drug delivery system (RBC@SIM-PEI-PPNPs). Results: The RBC@SIM-PEI-PPNPs delivery system effectively extended the drug's circulation time, providing an extended therapeutic window. Additionally, this method substantially improved the targeted accumulation of SIM in lung tissues, thereby enhancing the drug's efficacy in treating ARDS and impeding its progression to ARDS. Crucially, the system showed a reduced risk of adverse drug reactions. Conclusion: RBC@SIM-PEI-PPNPs demonstrates promise in ARDS and ARDS treatment. This innovative approach successfully overcomes the limitations associated with SIM's poor solubility and low bioavailability, resulting in improved therapeutic outcomes and fewer drug-related side effects. This research holds significant clinical implications and highlights its potential for broader application in drug delivery and lung disease treatment.

Clinical outcomes of corticosteroid administration for acute respiratory distress syndrome in adults based on meta-analyses and trial sequential analysis.

BACKGROUND: Acute respiratory distress syndrome (ARDS), which results in lung injury as a consequence of sepsis and septic shock, is associated with severe systemic inflammation and is responsible for a high worldwide mortality rate. OBJECTIVE: Investigate whether corticosteroids could benefit clinical outcomes in adult with ARDS. METHODS: A comprehensive search of electronic databases Ovid MEDLINE, Ovid EMbase, and Cochrane Library from their inception to 7 May 2023 was conducted to identify studies that met the eligibility criteria, including only randomized controlled trials. The study was performed in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines and the methods of trial sequential analysis. MAIN OUTCOME MEASURES: Mortality rates, including including the 14-, 28-, 45-, and 60-day mortality, hospital mortality, and intensive care unit (ICU) mortality. SAMPLE SIZE: 17 studies with 2508 patients. RESULTS: Data relating to mortality at 14, 28, 45, and 60 days were not significantly different when treatments with corticosteroids and placebo were compared. In terms of hospital and ICU mortality, the mortality of those who had received corticosteroids was significantly lower than that of those who had not. ARDS patients who received assisted ventilation benefited from corticosteroid therapy, as revealed by the significant difference in outcome days between those who received assisted ventilation and those who did not. Corticosteroid had significantly more days free from mechanical ventilation, ICU-free days, and MODS-free days during the first 28 days, but not more organ support-free days up to day 28. CONCLUSION: Although corticosteroid therapy did not reduce mortality rates at different observation periods, it significantly reduced hospital and ICU mortality. Administering corticosteroids to ARDS patients significantly decreased the days of assisted ventilation and time cost consumption. This study confirmed that long-term use of low-dose glucocorticoids may have a positive effect on early ARDS. LIMITATION: Risk of bias due to the differences in patient characteristics.

Mechanism Investigation and Clinical Retrospective Evaluation of Qingyi Granules: Pancreas Cleaner About Ameliorating Severe Acute Pancreatitis with Acute Respiratory Distress Syndrome.

Background: Despite its extensive utilization in Chinese hospitals for treating acute pancreatitis (AP) and related acute respiratory distress syndrome (ARDS), the active components and mechanisms underlying the action of Qingyi Granule (QYKL) remain elusive. Methods: This study consists of four parts. First, we used Mendelian randomization (MR) to investigate the causal relationship between AP, cytokine, and ARDS. Next, 321 patients were collected to evaluate the efficacy of QYKL combined with dexamethasone (DEX) in treating AP. In addition, we used UHPLC-QE-MS to determine the chemical constituents of QYKL extract and rat serum after the oral administration of QYKL. The weighted gene coexpression network analysis (WGCNA) method was used to find the main targets of AP-related ARDS using the GSE151572 dataset. At last, a AP model was established by retrograde injection of 5% sodium taurocholate. Results: MR showed that AP may have a causal relationship with ARDS by mediating cytokine storms. Retrospective study results showed early administration of QYKL was associated with a lower incidence of ARDS, mortality, admissions to the intensive care unit, and length of stay in AP patients compared to the Control group. Furthermore, we identified 23 QYKL prototype components absorbed into rat serum. WGCNA and differential expression analysis identified 1558 APALI-related genes. The prototype components exhibited strong binding activity with critical targets. QYKL has a significant protective effect on pancreatic and lung injury in AP rats, and the effect is more effective after combined treatment with DEX, which may be related to the regulation of the IL-6/STAT3 signaling pathway. Conclusion: By integrating MR, retrospective analysis, and systematic pharmacological methodologies, this study systematically elucidated the therapeutic efficacy of QYKL in treating AP-related ARDS, establishing a solid foundation for its medicinal use.

Standard vs. carbone dioxide adapted kidney replacement therapy in hypercapnic ARDS patients: a randomized controlled pilot trial (BigBIC).

BACKGROUND: Current continuous kidney replacement therapy (CKRT) protocols ignore physiological renal compensation for hypercapnia. This study aimed to explore feasibility, safety, and clinical benefits of pCO2-adapted CKRT for hypercapnic acute respiratory distress syndrome (ARDS) patients with indication for CKRT. METHODS: We enrolled mechanically ventilated hypercapnic ARDS patients (pCO2 > 7.33 kPa) receiving regional citrate anticoagulation (RCA) based CKRT in a prospective, randomized-controlled pilot-study across five intensive care units at the Charité-Universitätsmedizin Berlin, Germany. Patients were randomly assigned 1:1 to the control group with bicarbonate targeted to 24 mmol/l or pCO2-adapted-CKRT with target bicarbonate corresponding to physiological renal compensation. Study duration was six days. Primary outcome was bicarbonate after 72 h. Secondary endpoints included safety and clinical endpoints. Endpoints were assessed in all patients receiving treatment. RESULTS: From September 2021 to May 2023 40 patients (80% male) were enrolled. 19 patients were randomized to the control group, 21 patients were randomized to pCO2-adapted-CKRT. Five patients were excluded before receiving treatment: three in the control group (consent withdrawal, lack of inclusion criteria fulfillment (n = 2)) and two in the intervention group (lack of inclusion criteria fulfillment, sudden unexpected death) and were therefore not included in the analysis. Median plasma bicarbonate 72 h after randomization was significantly higher in the intervention group (30.70 mmol/l (IQR 29.48; 31.93)) than in the control group (26.40 mmol/l (IQR 25.63; 26.88); p < 0.0001). More patients in the intervention group received lung protective ventilation defined as tidal volume < 8 ml/kg predicted body weight. Thirty-day mortality was 10/16 (63%) in the control group vs. 8/19 (42%) in the intervention group (p = 0.26). CONCLUSION: Tailoring CKRT to physiological renal compensation of respiratory acidosis appears feasible and safe with the potential to improve patient care in hypercapnic ARDS. TRIAL REGISTRATION: The trial was registered in the German Clinical Trials Register (DRKS00026177) on September 9, 2021 and is now closed.

A comparative analysis of sivelestat sodium hydrate and ulinastatin combination therapy in the treatment of sepsis with acute respiratory distress syndrome.

OBJECTIVE: This comparative analysis aimed to investigate the efficacy of Sivelestat Sodium Hydrate (SSH) combined with Ulinastatin (UTI) in the treatment of sepsis with acute respiratory distress syndrome (ARDS). METHODS: A control group and an observation group were formed with eighty-four cases of patients with sepsis with ARDS, with 42 cases in each group. The control group was intravenously injected with UTI based on conventional treatment, and the observation group was injected with SSH based on the control group. Both groups were treated continuously for 7 days, and the treatment outcomes and efficacy of both groups were observed. The Murray Lung Injury Score (MLIS), Sequential Organ Failure Assessment (SOFA), and Acute Physiology and Chronic Health Evaluation II (APACHE II) were compared. Changes in respiratory function, inflammatory factors, and oxidative stress indicators were assessed. The occurrence of adverse drug reactions was recorded. RESULTS: The total effective rate in the observation group (95.24%) was higher than that in the control group (80.95%) (P < 0.05). The mechanical ventilation time, intensive care unit (ICU) hospitalization time, and duration of antimicrobial medication in the observation group were shorter and multiple organ dysfunction syndrome incidence was lower than those in the control group (P < 0.05). The mortality rate of patients in the observation group (35.71%) was lower than that in the control group (52.38%), but there was no statistically significant difference between the two groups (P > 0.05). MLIS, SOFA, and APACHE II scores in the observation group were lower than the control group (P < 0.05). After treatment, respiratory function, inflammation, and oxidative stress were improved in the observation group (P < 0.05). Adverse reactions were not significantly different between the two groups (P > 0.05). CONCLUSION: The combination of SSH plus UTI improves lung injury and pulmonary ventilation function, and reduces inflammation and oxidative stress in patients with sepsis and ARDS.

The clinical effectiveness of sivelestat in treating sepsis patients with both acute respiratory distress syndrome and septic cardiomyopathy.

BACKGROUND: We aimed to assess the efficacy of the neutrophil elastase inhibitor, sivelestat, in the treatment of sepsis-induced acute respiratory distress syndrome (ARDS) and septic cardiomyopathy (SCM). METHODS: Between January 2019 and December 2021, we conducted a randomized trial on patients who had been diagnosed with sepsis-induced acute respiratory distress syndrome (ARDS) and septic cardiomyopathy (SCM) at Wuhan Union Hospital. The patients were divided into two groups by random envelop method, the Sivelestat group and the Control group. We measured the serum concentrations of Interleukin (IL)-6, IL-8, Tumor necrosis factor-α (TNF-α), and High-mobility group box 1 (HMGB1) at five time points, which were the baseline, 12 h, 24 h, 48 h, and 72 h after admission to the ICU. We evaluated the cardiac function by sonography and the heart rate variability (HRV) with 24-hour Holter recording between the time of admission to the intensive care unit (ICU) and 72 h after Sivelestat treatment. RESULTS: From January 2019 to December 2021, a total of 70 patients were included in this study. The levels of IL-6, IL-8, and TNF-α were significantly lower in the Sivelestat group at different time points (12 h, 24 h, 48 h, and 72 h). HMGB1 levels were significantly lower at 72 h after Sivelestat treatment (19.46 ± 2.63pg/mL vs. 21.20 ± 2.03pg/mL, P = 0.003). The stroke volume (SV), tricuspid annular plane systolic excursion (TAPSE), early to late diastolic transmitral flow velocity (E/A), early (e') and late (a') diastoles were significantly low in the Control group compared with the Sivelestat group. Tei index was high in the Control group compared with the Sivelestat group (0.60 ± 0.08 vs. 0.56 ± 0.07, P = 0.029). The result of HRV showed significant differences in standard deviation of normal-to-normal intervals (SDNN), low frequency (LF), and LF/HF (high frequency) between the two groups. CONCLUSIONS: Sivelestat can significantly reduce the levels of serum inflammatory factors, improve cardiac function, and reduce heart rate variability in patients with Sepsis-induced ARDS and SCM.

Abscisic acid for acute respiratory distress syndrome therapy by suppressing alveolar macrophage pyroptosis via upregulating acyloxyacyl hydrolase expression.

OBJECTIVE: Abscisic acid (ABA) is a phytohormone that inhibits airway inflammation in acute respiratory distress syndrome (ARDS) mouse models. However, the molecular mechanism underlying this phenomenon remains unclear. METHODS: Serum ABA level in patients and mice was measured via liquid chromatography-tandem mass spectrometry (LC-MS/MS). In-depth molecular mechanism was investigated through transmission electron microscopy, RNA-sequencing, and molecular docking in ARDS mice and cultured primary alveolar macrophages (AMs). RESULTS: We found that the serum ABA level was remarkably decreased in ARDS mice and patients. ABA inhibited lipopolysaccharide (LPS)-induced airway inflammation in mice; moreover, it downregulated genes associated with pyroptosis, as shown by RNA-sequencing and lung protein immunoblots. ABA inhibited the formation of membrane pores in AMs and suppressed the cleavage of gasdermin D (GSDMD) and the activation of caspase-11 and caspase-1 in vivo and in vitro; however, the overexpression of caspase-11 reversed the protective effect of ABA on LPS-induced pyroptosis of primary AMs. ABA inhibited intra-AM LPS accumulation while increasing the level of acyloxyacyl hydrolase (AOAH) in AMs, whereas AOAH deficiency abrogated the suppressive action of ABA on inflammation, pyroptosis, and intra-AM LPS accumulation in vivo and in vitro. Importantly, ABA promoted its intracellular receptor lanthionine C-like receptor 2 interacting with transcription factor peroxisome proliferator-activated receptor γ, which ultimately leading to increase AOAH expression to inactivate LPS and inhibit pyroptosis in AMs. CONCLUSIONS: ABA protected against LPS-induced lung injury by inhibiting pyroptosis in AMs via proliferator-activated receptor γ-mediated AOAH expression.

Inhibition of aquaporin-9 ameliorates severe acute pancreatitis and associated lung injury by NLRP3 and Nrf2/HO-1 pathways.

Inflammation, apoptosis and oxidative stress play crucial roles in the deterioration of severe acute pancreatitis-associated acute respiratory distress syndrome (SAP-ARDS). Unfortunately, despite a high mortality rate of 45 %[1], there are limited treatment options available for ARDS outside of last resort options such as mechanical ventilation and extracorporeal support strategies[2]. This study investigated the potential therapeutic role and mechanisms of AQP9 inhibitor RG100204 in two animal models of severe acute pancreatitis, inducing acute respiratory distress syndrome: 1) a sodium-taurocholate induced rat model, and 2) and Cerulein and lipopolysaccharide induced mouse model. RG100204 treatment led to a profound reduction in inflammatory cytokine expression in pancreatic, and lung tissue, in both models. In addition, infiltration of CD68 + and CD11b + cells into these tissues were reduced in RG100204 treated SAP animals, and edema and SAP associated tissue damage were improved. Moreover, we demonstrate that RG100204 reduced apoptosis in the lungs of rat SAP animals, and reduces NF-κB signaling, NLRP3, expression, while profoundly increasing the Nrf2-dependent anti oxidative stress response. We conclude that AQP9 inhibition is a promising strategy for the treatment of pancreatitis and its systemic complications, such as ARDS.

An update on the pharmacological management of acute respiratory distress syndrome.

INTRODUCTION: Acute respiratory distress syndrome (ARDS) is characterized by acute inflammatory injury to the lungs, alterations in vascular permeability, loss of aerated tissue, bilateral infiltrates, and refractory hypoxemia. ARDS is considered a heterogeneous syndrome, which complicates the search for effective therapies. The goal of this review is to provide an update on the pharmacological management of ARDS. AREAS COVERED: The difficulties in finding effective pharmacological therapies are mainly due to the challenges in designing clinical trials for this unique, varied population of critically ill patients. Recently, some trials have been retrospectively analyzed by dividing patients into hyper-inflammatory and hypo-inflammatory sub-phenotypes. This approach has led to significant outcome improvements with some pharmacological treatments that previously failed to demonstrate efficacy, which suggests that a more precise selection of ARDS patients for clinical trials could be the key to identifying effective pharmacotherapies. This review is provided after searching the main studies on this topics on the PubMed and clinicaltrials.gov databases. EXPERT OPINION: The future of ARDS therapy lies in precision medicine, innovative approaches to drug delivery, immunomodulation, cell-based therapies, and robust clinical trial designs. These should lead to more effective and personalized treatments for patients with ARDS.

A phytomedicine extract exerts an anti-inflammatory response in the lungs by reducing STING-mediated type I interferon release.

BACKGROUND: Acute respiratory distress syndrome (ARDS) is an acute respiratory disease characterized by bilateral chest radiolucency and severe hypoxemia. Quzhou Fructus Aurantii ethyl acetate extract (QFAEE), which is prepared from the traditional Chinese respiratory anti-inflammatory natural herb Quzhou Fructus Arantii, has the potential to alleviate ARDS. In this work, we aimed to investigate the potential and mechanism underlying the action of QFAEE on ARDS and how QFAEE modulates the STING pathway to reduce type I interferon release to alleviate the inflammatory response. METHODS: Lipopolysaccharide (LPS), a potential proinflammatory stimulant capable of causing pulmonary inflammation with edema after nasal drops, was employed to model ARDS in vitro and in vivo. Under QFAEE intervention, the mechanism of action of QFAEE to alleviate ARDS was explored in this study. TREX1-/- mice were sued as a research model for the activation of the congenital STING signaling pathway. The effect of QFAEE on TREX1-/- mice could explain the STING-targeted effect of QFAEE on alleviating the inflammatory response. Our explorations covered several techniques, Western blot, histological assays, immunofluorescence staining, transcriptomic assays and qRT-PCR to determine the potential mechanism of action of QFAEE in antagonizing the inflammatory response in the lungs, as well as the mechanism of action of QFAEE in targeting the STING signaling pathway to regulate the release of type I interferon. RESULTS: QFAEE effectively alleviates ARDS symptoms in LPS-induced ARDS. We revealed that the mechanism underlying LPS-induced ARDS is the STING-TBK1 signaling pathway and further elucidated the molecular mechanism of QFAEE in the prevention and treatment of ARDS. QFAEE reduced the release of type I interferons by inhibiting the STING-TBK1-IRF3 axis, thus alleviating LPS-induced pneumonia and lung cell death in mice. Another key finding is that activation of the STING pathway by activators or targeted knockdown of the TREX1 gene can also induce ARDS. As expected, QFAEE was found to be an effective protective agent in alleviating ARDS and the antagonistic effect of QFAEE on ARDS was achieved by inhibiting the STING signaling pathway. CONCLUSIONS: The main anti-inflammatory effect of QFAEE was achieved by inhibiting the STING signaling pathway and reducing the release of type I interferons. According to this mechanism of effect, QFAEE can effectively alleviate ARDS and can be considered a potential therapeutic agent. In addition, the STING pathway plays an essential role in the development and progression of ARDS, and it is a potential target for ARDS therapy.

PNSC928, a plant-derived compound, specifically disrupts CtBP2-p300 interaction and reduces inflammation in mice with acute respiratory distress syndrome.

BACKGROUND: Prior research has highlighted the involvement of a transcriptional complex comprising C-terminal binding protein 2 (CtBP2), histone acetyltransferase p300, and nuclear factor kappa B (NF-κB) in the transactivation of proinflammatory cytokine genes, contributing to inflammation in mice with acute respiratory distress syndrome (ARDS). Nonetheless, it remains uncertain whether the therapeutic targeting of the CtBP2-p300-NF-κB complex holds potential for ARDS suppression. METHODS: An ARDS mouse model was established using lipopolysaccharide (LPS) exposure. RNA-Sequencing (RNA-Seq) was performed on ARDS mice and LPS-treated cells with CtBP2, p300, and p65 knockdown. Small molecules inhibiting the CtBP2-p300 interaction were identified through AlphaScreen. Gene and protein expression levels were quantified using RT-qPCR and immunoblots. Tissue damage was assessed via histological staining. KEY FINDINGS: We elucidated the specific role of the CtBP2-p300-NF-κB complex in proinflammatory gene regulation. RNA-seq analysis in LPS-challenged ARDS mice and LPS-treated CtBP2-knockdown (CtBP2KD), p300KD, and p65KD cells revealed its significant impact on proinflammatory genes with minimal effects on other NF-κB targets. Commercial inhibitors for CtBP2, p300, or NF-κB exhibited moderate cytotoxicity in vitro and in vivo, affecting both proinflammatory genes and other targets. We identified a potent inhibitor, PNSC928, for the CtBP2-p300 interaction using AlphaScreen. PNSC928 treatment hindered the assembly of the CtBP2-p300-NF-κB complex, substantially downregulating proinflammatory cytokine gene expression without observable cytotoxicity in normal cells. In vivo administration of PNSC928 significantly reduced CtBP2-driven proinflammatory gene expression in ARDS mice, alleviating inflammation and lung injury, ultimately improving ARDS prognosis. CONCLUSION: Our results position PNSC928 as a promising therapeutic candidate to specifically target the CtBP2-p300 interaction and mitigate inflammation in ARDS management.

Pulmonary drug delivery devices and nanosystems as potential treatment strategies for acute respiratory distress syndrome (ARDS).

Despite advances in drug delivery technologies, treating acute respiratory distress syndrome (ARDS) is challenging due to pathophysiological barriers such as lung injury, oedema fluid build-up, and lung inflammation. Active pharmaceutical ingredients (API) can be delivered directly to the lung site of action with the use of aerosol-based drug delivery devices, and this circumvents the hepatic first-pass effect and improves the bioavailability of drugs. This review discusses the various challenges and barriers for pulmonary drug delivery, current interventions for delivery, considerations for effective drug delivery, and the use of nanoparticle drug delivery carriers as potential strategies for delivering therapeutics in ARDS. Nanosystems have the added benefit of entrapping drugs, increase pulmonary drug bioavailability, and using biocompatible and biodegradable excipients that can facilitate targeted and/or controlled delivery. These systems provide an alternative to existing conventional systems. An effective way to deliver drugs for the treatment of ARDS can be by using colloidal systems that are aerosolized or inhaled. Drug distribution to the deeper pulmonary tissues is necessary due to the significant endothelial cell destruction that is prevalent in ARDS. The particle size of nanoparticles (<0.5 µm) makes them ideal candidates for treating ARDS as they can reach the alveoli. A look into the various potential benefits and limitations of nanosystems used for other lung disorders is also considered to indicate how they may be useful for the potential treatment of ARDS.

Exogenous surfactant for lung contusion causing ARDS: A systematic review of clinical and experimental reports.

This systematic review aimed to summarize the available data on the treatment of pulmonary contusions with exogenous surfactants, determine whether this treatment benefits patients with severe pulmonary contusions, and evaluate the optimal type of surfactant, method of administration, and drug concentration. Three databases (MEDline, Scopus, and Web of Science) were searched using the following keywords: pulmonary surfactant, surface-active agents, exogenous surfactant, pulmonary contusion, and lung contusion for articles published between 1945 and February 2023, with no language restrictions. Four reviewers independently rated the studies for inclusion, and the other four reviewers resolved conflicts. Of the 100 articles screened, six articles were included in the review. Owing to the limited number of papers on this topic, various types of studies were included (two clinical studies, two experiments, and two case reports). In all the studies, surfactant administration improved the selected ventilation parameters. The most frequently used type of surfactant was Curosurf® in the concentration of 25 mg/kg of ideal body weight. In most studies, the administration of a surfactant by bronchoscopy into the segmental bronchi was the preferable way of administration. In both clinical studies, patients who received surfactants required shorter ventilation times. The administration of exogenous surfactants improved ventilatory parameters and, thus, reduced the need for less aggressive artificial lung ventilation and ventilation days. The animal-derived surfactant Curosurf® seems to be the most suitable substance; however, the ideal concentration remains unclear. The ideal route of administration involves a bronchoscope in the segmental bronchi.

In Vivo Immune-Modulatory Activity of Lefamulin in an Influenza Virus A (H1N1) Infection Model in Mice.

Lefamulin is a first-in-class systemic pleuromutilin antimicrobial and potent inhibitor of bacterial translation, and the most recent novel antimicrobial approved for the treatment of community-acquired pneumonia (CAP). It exhibits potent antibacterial activity against the most prevalent bacterial pathogens that cause typical and atypical pneumonia and other infectious diseases. Early studies indicate additional anti-inflammatory activity. In this study, we further investigated the immune-modulatory activity of lefamulin in the influenza A/H1N1 acute respiratory distress syndrome (ARDS) model in BALB/c mice. Comparators included azithromycin, an anti-inflammatory antimicrobial, and the antiviral oseltamivir. Lefamulin significantly decreased the total immune cell infiltration, specifically the neutrophils, inflammatory monocytes, CD4+ and CD8+ T-cells, NK cells, and B-cells into the lung by Day 6 at both doses tested compared to the untreated vehicle control group (placebo), whereas azithromycin and oseltamivir did not significantly affect the total immune cell counts at the tested dosing regimens. Bronchioalveolar lavage fluid concentrations of pro-inflammatory cytokines and chemokines including TNF-α, IL-6, IL-12p70, IL-17A, IFN-γ, and GM-CSF were significantly reduced, and MCP-1 concentrations were lowered (not significantly) by lefamulin at the clinically relevant 'low' dose on Day 3 when the viral load peaked. Similar effects were also observed for oseltamivir and azithromycin. Lefamulin also decreased the viral load (TCID50) by half a log10 by Day 6 and showed positive effects on the gross lung pathology and survival. Oseltamivir and lefamulin were efficacious in the suppression of the development of influenza-induced bronchi-interstitial pneumonia, whereas azithromycin did not show reduced pathology at the tested treatment regimen. The observed anti-inflammatory and immune-modulatory activity of lefamulin at the tested treatment regimens highlights a promising secondary pharmacological property of lefamulin. While these results require confirmation in a clinical trial, they indicate that lefamulin may provide an immune-modulatory activity beyond its proven potent antibacterial activity. This additional activity may benefit CAP patients and potentially prevent acute lung injury (ALI) and ARDS.

Rosmarinic acid alleviates septic acute respiratory distress syndrome in mice by suppressing the bronchial epithelial RAS-mediated ferroptosis.

Activating angiotensin-converting enzyme 2 (ACE2) is an important player in the pathogenesis of septic-related acute respiratory distress syndrome (ARDS). Rosmarinic acid (RA) as a prominent polyphenolic secondary metabolite derived from Rosmarinus officinalis modulates ACE2 in sepsis remains unclear, although its impact on ACE inhibition and septic-associated lung injury has been explored. The study investigated the ACE2 expression in lipopolysaccharide (LPS)-induced lungs in mice and BEAS2B cells. Additionally, molecular docking, protein-protein interaction (PPI) network analysis, and western blotting were employed to predict and evaluate the molecular mechanism of RA on LPS-induced ferroptosis in vivo and in vitro. LPS-induced glutathione peroxidase 4 (GPX4) downregulation, ACE/ACE2 imbalance, and alteration of frequency of breathing (BPM), minute volume (MV), and the expiratory flow at 50% expired volume (EF50) were reversed by captopril pretreatment in vitro and in vivo. RA notably inhibited the infiltration into the lungs of neutrophils and monocytes with increased amounts of GPX4 and ACE2 proteins, lung function improvement, and decreased inflammatory cytokines levels and ER stress in LPS-induced ARDS in mice. Molecular docking showed RA was able to interact with ACE and ACE2. Moreover, combined with different pharmacological inhibitors to block ACE and ferroptosis, RA still significantly inhibited inflammatory cytokines Interleukin-1ß (IL-1ß), tumor necrosis factor-α (TNF-α), and C-X-C motif chemokine 2 (CXCL2) levels, as well as improved lung function, and enhanced GPX4 expression. Particularly, the anti-ferroptosis effect of RA in LPS-induced septic ARDS is RAS-dependent.

Oral beta-hydroxybutyrate alleviates COVID-19 related acute respiratory distress syndrome: A randomized, single-blind, placebo-controlled trial.

BACKGROUND: Acute respiratory distress syndrome (ARDS) is a lung complication of COVID-19 that requires intensive care and ventilation. Beta-hydroxybutyrate (BHB) is a ketone body that can modulate metabolism and inflammation in immune cells and lung tissues. We hypothesized that oral BHB could alleviate COVID-19 related ARDS by reducing pro-inflammatory cytokines and increasing anti-inflammatory cytokines. METHODS: We randomized 75 patients with mild (as per Berlin criteria) ARDS symptoms to receive oral 25 g twice daily or placebo for five days. The primary outcome was the change in pro-inflammatory cytokines (Interleukin-1ß, Interleukin-6, interleukin-18, tumour necrosis factor-alpha) and anti-inflammatory cytokine (interleukin-10) from baseline to day 5. The secondary outcomes were the change in BHB levels from baseline to day 5, the number of hospitalization days, and the occurrence of adverse events. RESULTS: Treatment with formulated BHB resulted in a significant decrease in pro-inflammatory cytokines; Interleukin-1ß (p = 0.0204), Interleukin-6 (p = 0.0309), interleukin-18 (p = 0.0116), tumour necrosis factor-alpha (p = 0.0489) and increase in interleukin-10 (p = 0.0246) compared treatment with placebo. Importantly, higher BHB levels (p = 0.0001) were observed after supplementation; additionally, patients who underwent this approach were hospitalized for fewer days. No serious adverse events were reported. CONCLUSION: Beta-hydroxybutyrate, an oral adjunct therapy, has shown promising results in ameliorating symptoms of ARDS. This includes reduced inflammation, oxidative stress, and decreased patient fatigue levels. Further study with a large sample size is warranted to assess the potential of BHB therapy's effectiveness in reducing the development of severe illness. CLINICAL TRIAL REGISTRATION: (http://ctri.nic.in/CTRI/2021/03/031790).

[Corticosteroids in intensive care medicine]. / Kortikosteroide in der Intensivmedizin.

In the case of septic shock, recent studies show benefits from a combination of hydrocortisone and fludrocortisone, but clear guideline recommendations are still lacking. For severe community-acquired pneumonia, early corticosteroid therapy is recommended. Corticosteroid therapy should not be used in influenza-associated community-acquired pneumonia. In contrast, a significantly lower 28-day mortality rate was observed for COVID-19 by the use of dexamethasone. Current guidelines also recommend the use of corticosteroids in Acute Respiratory Distress Syndrome. These recommendations are based primarily on studies that started steroid therapy early. However, many questions such as the type of corticosteroid, the timing and duration of therapy, and the dosage still remain unanswered.