Corticosteroids in ARDS

Xuanfei Baidu Decoction Alleviated Sepsis-Induced ALI by Modulating Gut Microbial Homeostasis and Promoting Inflammation Resolution: Bioinformatics and Experimental Study

The Xuanfei Baidu Decoction (XFBD) has shown effective therapeutic potential for acute lung injury (ALI) induced by lipopolysaccharide and immunoglobin G immune complexes. Herein, the protective effects and mechanisms of XFBD were investigated in a sepsis-induced ALI mouse model along with its effects on gut microbiota. Notably, bioinformatics and molecular docking analyses revealed that XFBD components exhibited a strong binding affinity to G-protein-coupled receptor 18 (GPR18). In the murine ALI model-induced by cecal ligation and puncture (CLP)-XFBD markedly improved lung histopathology, reduced M1 macrophage polarization, and decreased pro-inflammatory cytokine levels in both lung tissues and MH-S macrophages. Furthermore, XFBD downregulated key inflammatory pathways, including nuclear factor (NF)-κB, phosphorylated-NF-κB, CCAAT/enhancer binding protein-δ, and the nucleotide-binding oligomerization domain-like receptor pyrin domain-containing 3/Caspase-1/gasdermin D axis. Additionally, XFBD restored the CLP-induced disruption in gut microbiota balance, increasing the abundance of Prevotellaceae and Ruminococcaceae_UCG_014. Altogether, the findings of this study suggest that XFBD alleviates CLP-induced ALI by modulating gut microbial homeostasis and inhibiting associated inflammatory pathways, particularly via GPR18 activation, presenting the promising therapeutic potential of XFBD for treating sepsis-induced ALI.

Association of PIV value with early mortality in ICU patients with sepsis-associated acute kidney injury from the MIMIC IV database

Sepsis is a severe systemic inflammatory response, and sepsis-associated acute kidney injury (SA-AKI) is one of its most common complications. The pan-immune inflammation value (PIV), a novel inflammatory index, is designed to comprehensively reflect the status of systemic immune and inflammatory responses. However, the relationship between PIV and short-term clinical outcomes in SA-AKI patients remains unclear. This study was a retrospective analysis of SA-AKI patients from the MIMIC-IV database. The Boruta algorithm was used to identify key features predicting short-term mortality in SA-AKI patients. The relationships between ln (PIV) and all-cause mortality at 28 days and 90 days were assessed via multivariate Cox proportional hazards regression, subgroup analysis, sensitivity analysis, restricted cubic spline (RCS) modelling, and Kaplan‒Meier (K-M) survival analysis. A total of 4369 patients were included in the study, of whom 57.0% were male. Boruta analysis indicated that ln (PIV) was an important clinical feature. The results of multivariable Cox regression analysis revealed a positive correlation between ln (PIV) and mortality risk at both 28 days and 90 days (HR [95% CI] = 1.057 [1.009, 1.106], P = 0.019; HR [95% CI] = 1.075 [1.032, 1.120], P < 0.001). The RCS model revealed a nonlinear relationship between ln (PIV) and mortality at 28 and 90 days, with a critical threshold of 6.72. Above this threshold, a higher ln (PIV) was associated with increased mortality risk at both time points; sensitivity analyses confirmed that this association remained significant after specific patients were excluded. Subgroup analyses revealed that ln (PIV) significantly affected short-term mortality in diabetic patients (P < 0.05). Ln (PIV) is closely associated with short-term mortality in ICU patients with SA-AKI, suggesting its potential application in early risk assessment and clinical intervention.

PNSC5325 prevents acute respiratory distress syndrome by alleviating inflammation and inhibiting extracellular matrix degradation of alveolar macrophages

BACKGROUND

Acute respiratory distress syndrome (ARDS) is characterized by severe inflammation and significant extracellular matrix (ECM) degradation in the lungs. Our prior research identified the CtBP2-p300-NF-κB (C-terminal-binding protein 2-histone acetyltransferase p300-nuclear factor kappa B) transcriptional complex as critical in ARDS by activating pro-inflammatory cytokine genes.

METHODS

An ARDS mouse model was established using intratracheal instillation of lipopolysaccharide (LPS). Small molecules that inhibit the CtBP2-p300 interaction were identified through AlphaScreen. RNA sequencing (RNA-Seq) was conducted to determine differential gene expression. Immunoprecipitation and co-immunoprecipitation analyzed protein interactions. Reverse transcription-quantitative polymerase chain reaction (RT-qPCR) and immunoblotting detected gene and protein expression. Histological staining evaluated tissue damage.

RESULTS

Through AlphaScreen, two natural compounds, PNSC2477 and PNSC5325, were identified for their ability to inhibit the CtBP2-p300 interaction. While PNSC2477 demonstrated toxicity and was deemed unsuitable for further research, PNSC5325 exhibited minimal toxicity. PNSC5325 effectively inhibited the CtBP2-p300 interaction and reduced pro-inflammatory cytokine gene expression. RNA-Seq analysis of PNSC5325-treated cells indicated significant suppression of pro-inflammatory cytokine genes and matrix metalloproteinases (MMPs). Further molecular studies revealed that the CtBP2-p300 complex, in conjunction with activator protein 1 (AP1), activates MMP expression. PNSC5325 simultaneously suppressed both pro-inflammatory cytokines and MMPs by targeting the CtBP2-p300 complex. In LPS-injected mice, PNSC5325 administration significantly reduced ARDS incidence by inhibiting inflammatory and MMP genes.

CONCLUSION

These findings suggest that PNSC5325 protects against ARDS by inhibiting key inflammatory and ECM degradation pathways, highlighting its potential as a novel therapeutic agent for ARDS and paving the way for further clinical investigations.

[Impact of tumor lysis syndrome on the prognosis of pediatric mature B-cell lymphoma]

Objective: This study aimed to investigate the effect of tumor lysis syndrome (TLS) on the prognosis of children and adolescents with intermediate- or high-risk high-grade mature B-cell nonHodgkin lymphoma (HG B-NHL) . Methods: This study collected the clinical data and prognosis of 283 patients aged <18 years with newly diagnosed intermediate- or high-risk HG B-NHL treated at the Sun Yat-sen University Cancer Center from January 2010 to December 2022. The clinical characteristics, laboratory indicators during TLS, and prognosis of the patients were analyzed. The optimal cutoff values of laboratory indicators during TLS were identified using R studio according to event-free survival (EFS) . Results: Of the 283 patients enrolled, the median age was 7 (range: 1-18) years and the male-to-female ratio was 3.6∶1, 76 (26.9%) developed TLS, and 207 (73.1%) did not. Patients with TLS demonstrated higher proportions of the pathological subtype Burkitt lymphoma, high-risk stratification, age <12 years, and LDH of ≥1 000 IU/L compared with patients without TLS (all P<0.05). The 5-year EFS and overall survival (OS) rates of the entire group were (84.5±2.2) % and (88.2±2.0) %, respectively. The 5-year OS rate of patients with TLS was significantly lower than that of those without TLS [ (80.8±4.6) % vs (91.0±2.0) %, P=0.01]. Among patients with TLS, those with serum uric acid of ≤612.7 μmol/L (n=36) exhibited lower 5-year EFS [ (67.8±8.1) % vs (87.5±5.2) %, P=0.04] and OS rates [ (69.9±8.1) % vs (90.0±4.7) %, P=0.04] compared with those with uric acid of >612.7 μmol/L (n=40). Similarly, patients with serum phosphate of ≤1.89 mmol/L (n=58) demonstrated lower 5-year EFS [ (71.6±6.0) % vs 100%, P=0.02] and OS rates [ (74.8±5.8) % vs 100%, P=0.03] compared with those with phosphate of >1.89 mmol/L (n=18) . Conclusions: TLS is associated with poor prognosis in patients with HG B-NHL. Patients with lower serum uric acid and phosphate levels during TLS demonstrated worse prognoses, indicating their potential value in predicting prognosis and guiding stratified treatment.

Nanotherapy therapy for acute respiratory distress syndrome: a review

Acute respiratory distress syndrome (ARDS) is a complex and life-threatening disease characterized by severe respiratory failure. The lethality of ARDS remains alarmingly high, especially with the persistent ravages of coronavirus disease 2019 (COVID-19) in recent years. ARDS is one of the major complications of neocoronavirus pneumonia and the leading cause of death in infected patients. The large-scale outbreak of COVID-19 has greatly increased the incidence and mortality of ARDS. Despite advancements in our understanding of the causes and mechanisms of ARDS, the current clinical practice is still limited to the use of supportive medications to alleviate its progression. However, there remains a pressing need for effective therapeutic drugs to combat this devastating disease. In this comprehensive review, we discuss the commonly used therapeutic drugs for ARDS, including steroids, vitamin C, targeted inhibitors, and heparin. While these medications have shown some promise in managing ARDS, there is still a significant gap in the availability of definitive treatments. Moreover, we highlight the potential of nanocarrier delivery systems, such as liposomes, lipid nanoparticles, polymer nanoparticles, and inorganic nanoparticles, as promising therapeutic approaches for ARDS in the future. These innovative delivery systems have demonstrated encouraging results in early clinical trials and offer the potential for more targeted and effective treatment options. Despite the promising early results, further clinical trials are necessary to fully assess the efficacy and safety of nanotherapies for ARDS. Additionally, more in-depth research should be conducted to focus on the continuous development of precision therapies targeting different stages of ARDS development or different triggers. This will provide more ideas and rationale for the treatment of ARDS and ultimately lead to better patient outcomes.

Acute respiratory distress syndrome: A review of ARDS across the life course

Acute respiratory distress syndrome (ARDS) is a multifactorial, inflammatory lung disease with significant morbidity and mortality that predominantly requires supportive care in its management. Although initially described in adult patients, the diagnostic definitions for ARDS have evolved over time to accurately describe this disease process in pediatric and, more recently, neonatal patients. The management of ARDS in each age demographic has converged in the application of lung-protective ventilatory strategies to mitigate the primary disease process and prevent its exacerbation by limiting ventilator-induced lung injury. However, differences arise in the preferred ventilatory strategies or adjunctive pulmonary therapies used to mitigate each type of ARDS. In this review, we compare and contrast the epidemiology, common etiologies, pathophysiology, diagnostic criteria, and outcomes of ARDS across the lifespan. Additionally, we discuss in detail the different management strategies used for each subtype of ARDS and spotlight how these strategies were applied to mitigate poor outcomes during the COVID-19 pandemic. This review is geared toward both clinicians and clinician-scientists as it not only summarizes the latest information on disease pathogenesis and patient management in ARDS across the lifespan but also highlights knowledge gaps for further investigative efforts. We conclude by projecting how future studies can fill these gaps in research and what improvements may be envisioned in the management of NARDS and PARDS based on the current breadth of literature on adult ARDS treatment strategies.

Association of corticosteroid therapy with reduced acute kidney injury and lower NET markers in severe COVID-19: an observational study

BACKGROUND

Acute kidney injury (AKI) is common in critical cases of coronavirus disease 2019 (COVID-19) and associated with worse outcome. Dysregulated neutrophil extracellular trap (NET) formation is one of several suggested pathophysiological mechanisms involved in the development of COVID-19 associated AKI. The corticosteroid dexamethasone was implemented as a standard treatment for severe COVID-19 as of June 2020. A sub-analysis of a prospective observational single center study was performed to evaluate the effect of corticosteroid treatment on AKI development and NET markers in critical cases of COVID-19.

RESULTS

Two hundred and ten adult patients admitted to intensive care at a tertiary level hospital due to respiratory failure or shock secondary to SARS-CoV-2-infection between March 13th 2020 and January 14th 2021 were included in the study. Ninety-seven of those did not receive corticosteroids. One hundred and thirteen patients were treated with corticosteroids [dexamethasone (n = 98) or equivalent treatment (n = 15)], but the incidence of AKI was assessed only in patients that received corticosteroids before any registered renal dysfunction (n = 63). Corticosteroids were associated with a lower incidence of AKI (19% vs 55.8%, p < 0.001). Fewer patients demonstrated detectable concentrations of extracellular histones in plasma when treated with corticosteroids (8.7% vs 43.1%; p < 0.001). Extracellular histones and in particular non-proteolyzed histones were observed more frequently with increasing AKI severity (p < 0.001). MPO-DNA was found in lower concentrations in patients that received corticosteroids before established renal dysfunction (p = 0.03) and was found in higher concentrations in patients with AKI stage 3 (p = 0.03). Corticosteroids did not ameliorate established AKI during the first week of treatment.

CONCLUSION

Corticosteroid treatment in severe COVID-19 is associated with a lower incidence of AKI and reduced concentrations of NET markers in plasma.

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.

Specific Inhibition of Orai1-mediated Calcium Signalling Resolves Inflammation and Clears Bacteria in an Acute Respiratory Distress Syndrome Model

Rationale: Acute respiratory distress syndrome (ARDS) has an unacceptably high mortality rate (35%) and is without effective therapy. Orai1 is a Ca2+ channel involved in store-operated Ca2+ entry (SOCE), a process that exquisitely regulates inflammation. Orai1 is considered a druggable target, but no Orai1-specific inhibitors exist to date. Objectives: To evaluate whether ELD607, a first-in-class Orai1 antagonist, can treat ARDS caused by bacterial pneumonia in preclinical models. Methods: ELD607 pharmacology was evaluated in HEK293T cells and freshly isolated immune cells from patients with ARDS. A murine acute lung injury model caused by bacterial pneumonia was then used: mice were infected with Pseudomonas aeruginosa, Staphylococcus aureus, methicillin-resistant S. aureus, or multidrug-resistant P. aeruginosa and then treated with ELD607 intranasally. Measurements and Main Results: ELD607 specifically inhibited SOCE in HEK293T cells with a half-maximal inhibitory concentration of 9 nM. ELD607 was stable in ARDS airway secretions and inhibited SOCE in ARDS immune cells. In vivo, inhaled ELD607 significantly reduced neutrophilia and improved survival. Surprisingly, Orai1 inhibition by ELD607 caused a significant reduction in lung bacteria, including methicillin-resistant S. aureus. ELD607 worked as an immunomodulator that reduced cytokine levels, reduced neutrophilia, and promoted macrophage-mediated resolution of inflammation and clearance of bacteria. Indeed, when alveolar macrophages were depleted with inhaled clodronate, ELD607 was no longer able to resolve inflammation or clear bacteria. Conclusions: These data indicate that specific Orai1 inhibition by ELD607 may be a novel approach to reduce multiorgan inflammation and treat antibiotic-resistant bacteria.

Investigational pharmacological agents for the treatment of ARDS

INTRODUCTION

Acute Respiratory Distress Syndrome (ARDS) is a heterogeneous form of lung injury with severe hypoxemia and bilateral infiltrates after an inciting event that results in diffuse lung inflammation with a high mortality rate. While research in COVID-related ARDS has resulted in several pharmacotherapeutic agents that have undergone successful investigation, non-COVID ARDS studies have not resulted in many widely accepted pharmacotherapeutic agents despite exhaustive research.

AREAS COVERED

The aim of this review is to discuss adjuvant pharmacotherapies targeting non-COVID Acute Lung Injury (ALI)/ARDS and novel therapeutics in COVID associated ALI/ARDS. In ARDS, variable data may support selective use of neuromuscular blocking agents, corticosteroids and neutrophil elastase inhibitors, but are not yet universally used. COVID-ALI/ARDS has data supporting the use of IL-6 monoclonal antibodies, corticosteroids, and JAK inhibitor therapy.

EXPERT OPINION

Although ALI/ARDS modifying pharmacological agents have been identified in COVID-related disease, the data in non-COVID ALI/ARDS has been less compelling. The increased use of more specific molecular phenotyping based on physiologic parameters and biomarkers, will ensure equipoise between groups, and will likely allow more precision in confirming pharmacological agent efficacy in future studies.

Therapeutic utility of human umbilical cord-derived mesenchymal stem cells-based approaches in pulmonary diseases: Recent advancements and prospects

Pulmonary diseases across all ages threaten millions of people and have emerged as one of the major public health issues worldwide. For diverse disease conditions, the currently available approaches are focused on alleviating clinical symptoms and delaying disease progression but have not shown significant therapeutic effects in patients with lung diseases. Human umbilical cord-derived mesenchymal stem cells (UC-MSCs) isolated from the human UC have the capacity for self-renewal and multilineage differentiation. Moreover, in recent years, these cells have been demonstrated to have unique advantages in the treatment of lung diseases. We searched the Public Clinical Trial Database and found 55 clinical trials involving UC-MSC therapy for pulmonary diseases, including coronavirus disease 2019, acute respiratory distress syndrome, bronchopulmonary dysplasia, chronic obstructive pulmonary disease, and pulmonary fibrosis. In this review, we summarize the characteristics of these registered clinical trials and relevant published results and explore in depth the challenges and opportunitiesfaced in clinical application. Moreover, the underlying molecular mechanisms involved in UC-MSC-based therapy for pulmonary diseases are also analyzed in depth. In brief, this comprehensive review and detailed analysis of these clinical trials can be expected to provide a scientific reference for future large-scale clinical application.

Synergistic Pulmonoprotective Effect of Natural Prolyl Oligopeptidase Inhibitors in In Vitro and In Vivo Models of Acute Respiratory Distress Syndrome

Acute respiratory distress syndrome (ARDS) is a highly morbid inflammatory lung disease with limited pharmacological interventions. The present study aims to evaluate and compare the potential pulmonoprotective effects of natural prolyl oligopeptidase (POP) inhibitors namely rosmarinic acid (RA), chicoric acid (CA), epigallocatechin-3-gallate (EGCG) and gallic acid (GA), against lipopolysaccharide (LPS)-induced ARDS. Cell viability and expression of pro-inflammatory mediators were measured in RAW264.7 cells and in primary murine lung epithelial and bone marrow cells. Nitric oxide (NO) production was also assessed in unstimulated and LPS-stimulated RAW264.7 cells. For subsequent in vivo experiments, the two natural products (NPs) with the most favorable effects, RA and GA, were selected. Protein, cell content and lipid peroxidation levels in bronchoalveolar lavage fluid (BALF), as well as histopathological changes and respiratory parameters were evaluated in LPS-challenged mice. Expression of key mediators involved in ARDS pathophysiology was detected by Western blotting. RA and GA favorably reduced gene expression of pro-inflammatory mediators in vitro, while GA decreased NO production in macrophages. In LPS-challenged mice, RA and GA co-administration improved respiratory parameters, reduced cell and protein content and malondialdehyde (MDA) levels in BALF, decreased vascular cell adhesion molecule-1 (VCAM-1) and the inducible nitric oxide synthase (iNOS) protein expression, activated anti-apoptotic mechanisms and down-regulated POP in the lung. Conclusively, these synergistic pulmonoprotective effects of RA and GA co-administration could render them a promising prophylactic/therapeutic pharmacological intervention against ARDS.