Corticosteroids and ARDS: A review of treatment and prevention evidence

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.

Intubation in Eosinophilic Lung Disease: Predictors, Outcomes, and Characteristics from a National Inpatient Sample Analysis

Background and Objectives: Eosinophilic lung diseases (ELD) encompass disorders with an abnormally high number of polymorphonuclear eosinophils in the lungs. Presentation severity can range from low-grade fever and cough to life-threatening acute respiratory distress syndrome (ARDS). Due to the rarity of these conditions, no large sample studies have been performed to assess the characteristics of patients with pulmonary eosinophilia. Materials and Methods: Patients admitted with a diagnosis of pulmonary eosinophilia between the years 2016 and 2020 were extracted from the largest inpatient US database, the Nationwide Inpatient Sample (NIS). Patients under the age of eighteen and those with diabetic ketoacidosis were excluded. Baseline demographic characteristics and medical comorbidities were evaluated for individuals admitted with pulmonary eosinophilia depending on intubation requirement. The primary outcomes included in-hospital mortality, intubation, and length of stay (LOS). Results: 3784 records were extracted, among which 384 patients required intubation. Patients who required intubation had higher rates of in-hospital mortality (23.9% vs. 1.2% p < 0.0001%) and a significantly more prolonged hospital stay (19 days vs. 6 days p < 0.001) compared to patients who did not need intubation. Factors associated with mortality in the intubated group included increasing age (OR: 1.022, 95% CI 1.002-1.042), duration of intubation superior to 96 h (OR: 2.705, 95% CI 1.235-5.927), and AKI (OR: 2.964, 95% CI 1.637-5.366). Conclusions: Our findings suggest that ELD patients requiring intubation experience significantly higher rates of in-hospital mortality, acute kidney injury, deep venous thrombosis, and ARDS.

The association between early corticosteroid use and the risk of secondary infections in hospitalized patients with COVID-19: a double-edged sword. Results from the international SCCM discovery viral infection and respiratory illness universal study (VIRUS) COVID-19 registry

Background

Corticosteroids improve survival in hospitalized COVID-19 patients needing supplemental oxygen. However, concern exists about increased risk of secondary infections. This study investigated the impact of early corticosteroids use on these infections.

Methods

Data from the Society of Critical Care Medicine Discovery Viral Infection and Respiratory Illness Universal Study (VIRUS): COVID-19 registry were analyzed for adult patients, stratified by early corticosteroid use (within 48 h of admission). The primary outcome was documented secondary infections, including bacteremia, bacterial pneumonia, empyema, meningitis/encephalitis, septic shock, and ventilator-associated pneumonia. Univariate and multivariable logistic regression models were used to assess the association between early corticosteroids and these outcomes.

Results

Among 17,092 eligible patients, with 13.5% developed at least one secondary bacterial infection during hospitalization. Patients receiving early corticosteroids were older (median 63 years) compared to those who did not (median 60 years), with a similar gender distribution (42.5% vs. 44.2% female). Unadjusted analysis revealed a higher risk for any secondary infection (OR 1.93, 95% CI 1.76-2.12). This association persisted for specific infections including bacteremia (OR 2.0, 95% CI 1.58-2.54), bacterial pneumonia (OR 1.5, 95% CI 1.27-1.77), and septic shock (OR 1.67, 95% CI 1.44-1.93). However, the effect on meningitis/encephalitis (OR 0.62, 95% CI 0.24-1.57) and ventilator-associated pneumonia (VAP; OR 1.08, 95% CI 0.75-1.57) was non-significant. Adjusted analysis maintained significance for any secondary infection (OR 1.15, 95% CI 1.02-1.29), bacteremia (OR 1.43, 95% CI 1.09-1.88), and infections with unknown sources (OR 1.63, 95% CI 1.31-2.02). Notably, the association weakened and became non-significant for bacterial pneumonia (OR 0.98, 95% CI 0.81-1.20) and septic shock (OR 0.94, 95% CI 0.79-1.11), while it became significant for meningitis/encephalitis (OR 0.26, 95% CI 0.08-0.82). VAP remained non-significant (OR 0.87, 95% CI 0.56-1.34).

Conclusion

Early use of corticosteroids increased overall secondary infection risk in hospitalized COVID-19 patients, but the impact varied. Risk of bacteremia was notably increased, while the association with bacterial pneumonia and septic shock weakened after adjustment becoming non-significant and surprisingly reduced meningitis/encephalitis risk was noted suggesting the complexity of corticosteroid effects. Further research is needed to understand how corticosteroids influence specific secondary infections, and thereby optimize the treatment strategies.

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.

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.

Risk factors for acute respiratory distress syndrome in sepsis patients: A meta-analysis

Background

Acute Respiratory Distress Syndrome (ARDS) is a critical complication of sepsis, associated with high morbidity and mortality. Identifying risk factors for ARDS among sepsis patients is essential for early intervention and improving outcomes.

Methods

We conducted a comprehensive meta-analysis, reviewing studies that examined the association between various risk factors and ARDS development in sepsis patients. Databases such as PubMed, EMBASE, Cochrane Library, Medline, CINAHL, and Web of Science were searched up to January 2024, without language restrictions. Eligible studies included observational cohorts and case-control studies. Pooled odds ratios (ORs) and standardized mean differences (SMDs) were calculated using a random-effects model. Heterogeneity was assessed through I2 statistics, and publication bias was evaluated via the Luis Furuya-Kanamori (LFK) index.

Results

15 studies with more than 40,000 participants were analyzed. Significant risk factors for ARDS included pulmonary infection (OR: 2.696, 95 % CI: 1.655 to 4.390), septic shock (OR: 2.627, 95 % CI: 1.850 to 3.731), and pancreatitis (OR: 3.734, 95 % CI: 2.958 to 4.712). No significant associations were found between the development of ARDS in septic patients and the following risk factors: sex (OR: 1.106, 95%CI: 0.957-1.279), smoking status (OR: 1.214, 95%CI: 0.835-1.765), or steroid use (OR: 0.901, 95%CI: 0.617-1.314). APACHE-II and SOFA scores were predictive of ARDS development, emphasizing their utility in clinical assessments.

Conclusion

Pulmonary infection, septic shock, and pancreatitis significantly increase ARDS risk in sepsis patients. Our findings advocate for targeted management of these risk factors to mitigate ARDS development, emphasizing the importance of personalized care in sepsis management.

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.

Acute Respiratory Failure in Severe Acute Brain Injury

Acute respiratory failure is commonly encountered in severe acute brain injury due to a multitude of factors related to the sequelae of the primary injury. The interaction between pulmonary and neurologic systems in this population is complex, often with competing priorities. Many treatment modalities for acute respiratory failure can result in deleterious effects on cerebral physiology, and secondary brain injury due to elevations in intracranial pressure or impaired cerebral perfusion. High-quality literature is lacking to guide clinical decision-making in this population, and deliberate considerations of individual patient factors must be considered to optimize each patient's care.

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.

LC-QToF chemical profiling of Euphorbia grantii Oliv. and its potential to inhibit LPS-induced lung inflammation in rats via the NF-κB, CY450P2E1, and P38 MAPK14 pathways

Acute lung injury (ALI) is a life-threatening syndrome that causes high morbidity and mortality worldwide. The aerial parts of Euphorbia grantii Oliv. were extracted with methanol to give a total methanolic extract (TME), which was further fractionated into dichloromethane (DCMF) and the remaining mother liquor (MLF) fractions. Biological guided anti-inflammatory assays in vitro revealed that the DCMF showed the highest activity (IC50 6.9 ± 0.2 μg/mL and 0.29 ± 0.01 μg/mL) compared to. celecoxib (IC50 of 88.0 ± 1 μg/mL and 0.30 ± 0.01 μg/mL) on COX-1 and COX-2, respectively. Additionally, anti-LOX activity was IC50 = 24.0 ± 2.5 μg/mL vs. zileuton with IC50 of 40.0 ± 0.5 μg/mL. LC-DAD-QToF analysis of TME and the active DCMF resulted in the tentative identification and characterization of 56 phytochemical compounds, where the diterpenes were the dominated metabolites. An LPS-induced inflammatory model of ALI (10 mg/kg i.p) was used to assess the anti-inflammatory potential of DCMF in vivo at dose of 200 mg/kg and 300 mg/kg compared to dexamethasone (5 mg/kg i.p). Our treatments significantly reduced the pro-inflammatory cytokines (TNF-α, IL-1, IL-6, and MPO), increased the activity of antioxidant enzymes (SOD, CAT, and GSH), decreased the activity of oxidative stress enzyme (MDA), and reduced the expression of inflammatory genes (p38.MAPK14 and CY450P2E1). The western blotting of NF-κB p65 in lung tissues was inhibited after orally administration of the DCMF. Histopathological study of the lung tissues, scoring, and immunohistochemistry of transforming growth factor-beta 1 (TGF-β1) were also assessed. In both dose regimens, DCMF of E. grantii prevented further lung damage and reduced the side effects of LPS on acute lung tissue injury.

Corticosteroids in ARDS

Acute respiratory distress syndrome (ARDS) is frequently associated with sepsis. ARDS and sepsis exhibit a common pathobiology, namely excessive inflammation. Corticosteroids are powerful anti-inflammatory agents that are routinely used in septic shock and in oxygen-dependent SARS-CoV-2 related acute respiratory failure. Recently, corticosteroids were found to reduce mortality in severe community-acquired pneumonia. Corticosteroids may therefore also have a role to play in the treatment of ARDS. This narrative review was undertaken following a PubMed search for English language reports published before January 2023 using the terms acute respiratory distress syndrome, sepsis and steroids. Additional reports were identified by examining the reference lists of selected articles and based on personnel knowledge of the authors of the field. High-quality research is needed to fully understand the role of corticosteroids in the treatment of ARDS and to determine the optimal timing, dosing and duration of treatment.

Exploring m6A-RNA methylation as a potential therapeutic strategy for acute lung injury and acute respiratory distress syndrome

N6-methyladenosine (m6A) is the most common methylation modification in mammalian messenger RNA (mRNA) and noncoding RNAs. m6A modification plays a role in the regulation of gene expression and deregulation of m6A methylation has been implicated in many human diseases. Recent publications suggest that exploitation of this methylation process may possess utility against acute lung injury (ALI). ALI and its more severe form, acute respiratory distress syndrome (ARDS) are acute, inflammatory clinical syndromes characterized by poor oxygenation and diffuse pulmonary infiltrates. This syndrome is associated with microvascular endothelial dysfunction, subsequent pulmonary hypertension and may ultimately lead to mortality without rigorous and acute clinical intervention. Over the years, many attempts have been made to detect novel therapeutic avenues for research without much success. The urgency for the discovery of novel therapeutic agents has become more pronounced recently given the current pandemic infection of coronavirus disease 2019 (COVID-2019), still ongoing at the time that this review is being written. We review the current landscape of literature regarding ALI and ARDS etiology, pathophysiology, and therapeutics and present a potential role of m6A methylation. Additionally, we will establish the axiomatic principles of m6A methylation to provide a framework. In conclusion, METTL3, or methyltransferase-like 3, the selective RNA methyltransferase for m6A, is a hub of proinflammatory gene expression regulation in ALI, and using a modern drug discovery strategy will identify new and effective ALI drug candidates targeting METTTL3.

Interventions and outcomes of COVID-19 patients in a community hospital-A single center study comparing the first and second waves

BACKGROUND

We have had 3 coronavirus-related pandemics in the last two decades. Each has brought significant toll and with each case there was no cure. Even as vaccines have been developed for the current strain of the virus thereby increasing the prospects of bringing transmissions in communities to a minimum, lessons from this pandemic should be explored in preparation for future pandemics. Other studies have looked at differences in characteristics of patients and mortality rates between the first two waves. In our study we not only identify the differences in outcomes but also explore differences in hospital specific interventions that were implemented at Jersey City Medical Center, NJ, a community-based hospital.

AIM

The aim of this study is to assess the differences between the first two waves of the COVID -19 pandemic in terms of management and outcomes to help identify any key lessons in the handling of future pandemics. We compared the population demographics, interventions and outcomes used during the first two waves of COVID-19 in a community-based hospital.

METHODS

This is a retrospective single-center cross-sectional study including Laboratory confirmed COVID-19 patients requiring oxygen supplementation admitted at Jersey City Medical Center during the first wave (April 1 to June 30, 2020) and the second wave between (October 1, 2020, and January 1, 2021). The Chi-squared test was used to assess the relationship between categorical variables and the T- test for continuous variables. A Logistic regression model was built comparing the second to the first wave while accounting for important covariates.

RESULTS

There was a combined total of 473 patients from both waves. Patients in the first wave were older (66.17 years vs 60.38 years, p <0.01), had more comorbidities (2.75 vs 2.29, p 0.003), had more severe disease (50% vs 38.78% p of 0.002), had a longer length of stay (14.18 days vs 8.77 days, p <0.001) and were more likely to be intubated (32.49% vs 21.9 4%, p 0.01). In the univariate model, the odds of mortality in the second wave compared to the first wave was 0.63 (CI, 0.41-0.96) and 1.73 (CI, 0.65-4.66) in the fully adjusted model.

CONCLUSION

Overall, there was no statistically significant difference in mortality between the two waves. Interventions that were noted to be significantly different between the two waves were, increased likelihood of mechanical intubation in the first wave and increased use of steroids in the second wave compared to the first.

Glucocorticoids and COVID-19

Coronavirus Disease 19 (COVID-19) is associated with high morbidity and mortality rates globally, representing the greatest health and economic challenge today. Several drugs are currently approved for the treatment of COVID-19. Among these, glucocorticoids (GCs) have received particular attention due to their anti-inflammatory and immunosuppressive effects. In fact, GC are widely used in current clinical practice to treat inflammatory, allergic and autoimmune diseases. Major mechanisms of GC action include inhibition of innate and adaptive immune activity. In particular, an important role is played by the inhibition of pro-inflammatory cytokines and chemokines, and the induction of proteins with anti-inflammatory activity. Overall, as indicated by various national and international regulatory agencies, GCs are recommended for the treatment of COVID-19 in patients requiring oxygen therapy, with or without mechanical ventilation. Regarding the use of GCs for the COVID-19 treatment of non-hospitalized patients at an early stage of the disease, many controversial studies have been reported and regulatory agencies have not recommended their use. The decision to start GC therapy should be based not only on the severity of COVID-19 disease, but also on careful considerations of the benefit/risk profile in individual patients, including monitoring of adverse events. In this review we summarize the effects of GCs on the major cellular and molecular components of the inflammatory/immune system, the benefits and the adverse common reactions in the treatment of inflammatory/autoimmune diseases, as well as in the management of COVID-19.

Indications, Clinical Utility, and Safety of Bronchoscopy in COVID-19

BACKGROUND

Bronchoscopy is an aerosol-generating procedure and routine use for patients with coronavirus disease 2019 (COVID-19) has been discouraged. The purpose of this review was to discuss the indications, clinical utility, and risks associated with bronchoscopy in patients with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pneumonia.

METHODS

A literature search was performed by using appropriate key terms to identify all relevant articles from medical literature databases up to August 1, 2021.

RESULTS

Twelve cohorts (9 retrospective and 3 prospective) reported the performance of 2,245 bronchoscopies in 1,345 patients with COVID-19. The majority of the subjects were male. Nearly two thirds of the bronchoscopies (62%) were performed for therapeutic indications; the rest (38%) were for diagnostic purposes. Bronchoalveolar lavage had an overall yield of 33.1% for SARS-CoV-2 in subjects with negative results of real-time polymerase chain reaction on nasopharyngeal specimens. The incidence of a secondary infection ranged from 9.3% to as high as 65%. Antibiotics were changed in a significant number of the subjects (14%-83%) based on the bronchoscopic findings. Bronchoscopy was well tolerated in most subjects except those who required noninvasive ventilation, in whom the intubation rate after the procedure was 60%. The rate of transmission of SARS-CoV-2 among health-care workers was minimum.

CONCLUSIONS

Bronchoscopy in patients with COVID-19 results in a significant change in patient management. Transmission of SARS-CoV-2 seems to be low with consistent use of appropriate personal protective equipment by health-care workers. Therefore, bronchoscopic evaluation should be considered for all diagnostic and therapeutic indications in this patient population.

Gene Therapy for Acute Respiratory Distress Syndrome

Acute respiratory distress syndrome (ARDS) is a devastating clinical syndrome that leads to acute respiratory failure and accounts for over 70,000 deaths per year in the United States alone, even prior to the COVID-19 pandemic. While its molecular details have been teased apart and its pathophysiology largely established over the past 30 years, relatively few pharmacological advances in treatment have been made based on this knowledge. Indeed, mortality remains very close to what it was 30 years ago. As an alternative to traditional pharmacological approaches, gene therapy offers a highly controlled and targeted strategy to treat the disease at the molecular level. Although there is no single gene or combination of genes responsible for ARDS, there are a number of genes that can be targeted for upregulation or downregulation that could alleviate many of the symptoms and address the underlying mechanisms of this syndrome. This review will focus on the pathophysiology of ARDS and how gene therapy has been used for prevention and treatment. Strategies for gene delivery to the lung, such as barriers encountered during gene transfer, specific classes of genes that have been targeted, and the outcomes of these approaches on ARDS pathogenesis and resolution will be discussed.

Nitric-Oxide-Releasing Dexamethasone Derivative NCX-1005 Improves Lung Function and Attenuates Inflammation in Experimental Lavage-Induced ARDS

Acute respiratory distress syndrome (ARDS) is a common complication of critical illness and remains a major source of morbidity and mortality in the intensive care unit (ICU). ARDS is characterised by diffuse lung inflammation, epithelial and endothelial deterioration, alveolar–capillary leak and oedema formation, and worsening respiratory failure. The present study aimed to investigate the anti-inflammatory activity of nitric-oxide-releasing dexamethasone derivative NCX-1005 as a potential novel drug for ARDS. Adult rabbits with lavage-induced ARDS were treated with dexamethasone i.v. (0.5 mg/kg; DEX) and nitro-dexamethasone i.v. (0.5 mg/kg, NCX-1005) or were untreated (ARDS). Controls represented healthy ventilated animals. The animals were subsequently oxygen-ventilated for an additional 4 h and respiratory parameters were recorded. Lung oedema, inflammatory cell profile in blood and bronchoalveolar lavage, levels of the cytokines (IL-1β, IL-6, IL-8, TNF-α), and oxidative damage (TBARS, 3NT) in the plasma and lung were evaluated. Nitric oxide-releasing dexamethasone derivative NCX-1005 improved lung function, reduced levels of cytokines, oxidative modifications, and lung oedema formation to similar degrees as dexamethasone. Only NCX-1005 prevented the migration of neutrophils into the lungs compared to dexamethasone. In conclusion, the nitric oxide-releasing dexamethasone derivative NCX-1005 has the potential to be effective drug with anti-inflammatory effect in experimental ARDS.

The Effect of a Combined Ganciclovir, Methylprednisolone, and Immunoglobulin Regimen on Survival and Functional Outcomes in Patients With Japanese Encephalitis

Objective: There is currently no effective treatment for Japanese encephalitis, which has a high rate of morbidity and mortality. This study assessed the effectiveness of a ganciclovir, methylprednisolone, and immunoglobulin combination (TAGMIC) therapy in decreasing cognitive impairment and mortality among patients with Japanese encephalitis.

Methods: We retrospectively assessed the clinical data of 31 patients diagnosed with Japanese encephalitis, who were admitted to an intensive care unit. Patients were divided into the TAGMIC and non-TAGMIC group according to their treatment regime. We compared the 60-day, 6-month, and overall mortality and survival curves between groups. We also compared Barthel Index scores, Montreal Cognitive Assessment (MoCA) scores, and diffusion tensor imaging (DTI) results.

Results: There was no significant difference in the 30-day mortality rate or Kaplan–Meier survival curve between groups. The 60-day, 6-month, and overall mortality rates in the TAGMIC group were significantly reduced (P = 0.043, P = 0.018, and P = 0.018, respectively) compared with the non-TAGMIC group (0, 0, 0 vs. 31.25, 37.5, 37.5%, respectively). The 60-day, 6-month, and overall Kaplan–Meier survival curves were significantly different between groups (P = 0.020, P = 0.009, P = 0.009, respectively). There was no significant difference in the Barthel Index scores of surviving patients. Among the five patients who underwent MoCA and DTI, four had a score of 0/5 for delayed recall (no cue), while the remaining patient had a score of 2/5. All five patients were able to achieve a score of 5/5 with classification and multiple-choice prompts, and had sparse or broken corpus callosum (or other) fibre bundles.

Conclusion: TAGMIC treatment can reduce mortality due to severe Japanese encephalitis. The memory loss of surviving patients is mainly due to a disorder of the memory retrieval process, which may be related to the breakage of related fibre bundles.

Comparison of standard dose with high dose of methylprednisolone in the management of COVID-19 patients admitted in ICU

CONTEXT

The pathological progression in severe Coronavirus Disease 2019 (COVID-19) includes an excessive and unregulated pro-inflammatory cytokine storm. Though the efficacy of corticosteroids like methylprednisolone (MPS) in severe COVID-19 is proven now, its dose and duration are not precise.

AIMS

Our study aimed to compare the effect of a standard dose (SD) of MPS (60-120 mg/day) to a high dose (HD) of MPS (>120 mg/day) on the outcome of hospitalized COVID-19 patients.

SETTINGS AND DESIGN

This study was a cross-sectional study. Patients admitted to AIIMS, Bhopal's intensive care unit (ICU) from July 2020 to March 2021 were enrolled in the study.

METHODS AND MATERIAL

The patient's medical records were extracted from the medical record section of the hospital. The primary endpoint was the all-cause mortality during the hospital stay. The secondary endpoints were the need for mechanical ventilation, the use of vasopressors, the occurrence of acute kidney injury (AKI), and secondary infections.

STATISTICAL ANALYSIS USED

Data were entered in the MS Excel spreadsheet and coded appropriately.

RESULTS

Our data showed that survival, the need for mechanical ventilation, the occurrence of AKI, and secondary bacterial infection are comparable among the two groups with no significant difference. The logistic regression analysis showed that there is a slightly higher risk of death for patients with an acute respiratory distress syndrome (ARDS) receiving HD of corticosteroids compared to SD, though these results were found to be statistically non-significant.

CONCLUSIONS

In hospitalized patients suffering from severe COVID-19 pneumonia, an SD of MPS is as effective as an HD of MPS in terms of reduction in mortality and need for mechanical ventilation.

The Role of Glucocorticoids in Inflammatory Diseases

For more than 70 years, glucocorticoids (GCs) have been a powerful and affordable treatment option for inflammatory diseases. However, their benefits do not come without a cost, since GCs also cause side effects. Therefore, strong efforts are being made to improve their therapeutic index. In this review, we illustrate the mechanisms and target cells of GCs in the pathogenesis and treatment of some of the most frequent inflammatory disorders affecting the central nervous system, the gastrointestinal tract, the lung, and the joints, as well as graft-versus-host disease, which often develops after hematopoietic stem cell transplantation. In addition, an overview is provided of novel approaches aimed at improving GC therapy based on chemical modifications or GC delivery using nanoformulations. GCs remain a topic of highly active scientific research despite being one of the oldest class of drugs in medical use.

Corticosteroid use in ARDS and its application to evolving therapeutics for coronavirus disease 2019 (COVID-19): A systematic review

Data regarding the use of corticosteroids for treatment of acute respiratory distress syndrome (ARDS) are conflicting. As the coronavirus disease 2019 (COVID‐19) pandemic progresses, more literature supporting the use of corticosteroids for COVID‐19 and non‐COVID‐19 ARDS have emerged. Glucocorticoids are proposed to attenuate the inflammatory response and prevent progression to the fibroproliferative phase of ARDS through their multiple mechanisms and anti‐inflammatory properties. The purpose of this systematic review was to comprehensively evaluate the literature surrounding corticosteroid use in ARDS (non‐COVID‐19 and COVID‐19) in addition to a narrative review of clinical considerations of corticosteroid use in these patient populations. OVID Medline and EMBASE were searched. Randomized controlled trials evaluating the use of corticosteroids for COVID‐19 and non‐COVID‐19 ARDS in adult patients on mortality outcomes were included. Risk of bias was assessed with the Risk of Bias 2.0 tool. There were 388 studies identified, 15 of which met the inclusion criteria that included a total of 8877 patients. The studies included in our review reported a mortality benefit in 6/15 (40%) studies with benefit being seen at varying time points of mortality follow‐up (ICU survival, hospital, and 28 and 60 days) in the COVID‐19 and non‐COVID‐19 ARDS studies. The two non‐COVID19 trials assessing lung injury score improvements found that corticosteroids led to significant improvements with corticosteroid use. The number of mechanical ventilation‐free days significantly were found to be increased with the use of corticosteroids in all four studies that assessed this outcome. Corticosteroids are associated with improvements in mortality and ventilator‐free days in critically ill patients with both COVID‐19 and non‐COVID‐19 ARDS, and evidence suggests their use should be encouraged in these settings. However, due to substantial differences in the corticosteroid regimens utilized in these trials, questions still remain regarding the optimal corticosteroid agent, dose, and duration in patients with ARDS.

Steroid therapy for COVID-19: A systematic review and meta-analysis of randomized controlled trials

There is an urgent need for effective treatment modalities for coronavirus disease 2019 (COVID-19). Data for the use of steroids in COVID-19 is emerging. We conducted this systematic review and meta-analysis to estimate the effectiveness of steroid administration in mortality reduction due to COVID-19 compared to the control group. A systematic search of the Pubmed and Embase databases was performed to extract randomized controlled trials (RCTs) regarding the use of steroid therapy for COVID-19. An overall and subgroup (based upon the type of steroid) pooled mortality analysis was performed, and odds ratios were reported. Cochrane risk of bias assessment tool was used to assess the risk of bias. Heterogeneity was assessed using the I2 statistic. Six RCTs, including 7707 patients, were selected for review. Three trials reported 28-day mortality, and two trials reported 21-day mortality, and one trial reported in-hospital mortality. There were 730 deaths among 2837 participants in the steroid group while 1342 deaths among 4870 patients randomized to the control group (Odds ratio 0.76, 95% confidence interval 0.58-1.00, p=0.05). The effect was significant in patients on oxygen or mechanical ventilation. There was no difference in the various preparations and doses of the steroids. There was heterogeneity among the trials as the I2 value was 53%, with a p-value of 0.06. There was no indication of increased serious adverse events. This meta-analysis of RCTs demonstrated that the use of systemic corticosteroids is associated with a reduction in all-cause mortality in patients with COVID-19 on oxygen or mechanical ventilation.

Nanotherapeutics in the treatment of acute respiratory distress syndrome

Acute respiratory distress syndrome (ARDS) is a form of oxygenation failure primarily characterized by rapid inflammation resulting from a direct pulmonary or indirect systemic insult. ARDS has been a major cause of death in the recent COVID-19 outbreak wherein asymptomatic respiratory tract infection progresses to ARDS from pneumonia have emphasized the need for a reliable therapy for the disease. The disease has a high mortality rate of approximately 30-50%. Despite the high mortality rate, a dearth of effective pharmacotherapy exists that demands extensive research in this area. The complex ARDS pathophysiology which remains to be understood completely and the multifactorial etiology of the disease has led to the poor diagnosis, impeded drug-delivery to the deeper pulmonary tissues, and delayed treatment of the ARDS patients. Besides, critically ill patients are unable to tolerate the off-target side effects. The vast domain of nanobiotechnology presents several drug delivery systems offering numerous benefits such as targeted delivery, prolonged drug release, and uniform drug-distribution. The present review presents a brief insight into the ARDS pathophysiology and summarizes conventional pharmacotherapies available to date. Furthermore, the review provides an updated report of major developments in the nanomedicinal approaches for the treatment of ARDS. We also discuss different nano-formulations studied extensively in the ARDS preclinical models along with underlining the advantages as well as challenges that need to be addressed in the future.

Botanical formulation, TADIOS, alleviates lipopolysaccharide (LPS)-Induced acute lung injury in mice via modulation of the Nrf2-HO-1 signaling pathway

ETHNOPHARMACOLOGICAL RELEVANCE

TADIOS is an herbal formulation prepared from a mixture of Taraxacum officinale (L.) Weber ex F.H.Wigg, Dioscorea batatas Decaisne and Schizonepeta tenuifolia (Benth.) Briquet. These plants have traditionally been used in Asia to treat a variety of respiratory diseases. A bulk of literature on traditional Korean medicine describe their activities and functions for respiratory problems. Therefore, we hypothesized that the combination of these plants might be effective in alleviating respiratory symptoms.

AIM OF THE STUDY

In this study, we investigated whether TADIOS ameliorates LPS-induced acute lung injury via regulation of the Nrf2-HO-1 signaling pathway.

MATERIALS AND METHODS

The LPS-induced acute lung injury mouse model was used to determine the anti-inflammatory and anti-oxidative stress effects of TADIOS. The amount of marker compounds contained in TADIOS was quantified using high-performance liquid chromatography (HPLC) analysis. The protein level of pro-inflammatory cytokines in culture supernatant was measured by ELISA. Changes in the RNA level of pro-inflammatory cytokines in mice lungs and RAW264.7 cells were measured by quantitative RT-PCR. The relative amounts of reactive oxygen species (ROS) were measured by DCF-DA assay. Western blot analysis was used to evaluate expression of cellular proteins. Effects of TADIOS on antioxidant responsive elements (AREs) were determined by luciferase assay. The severity of acute lung injury was evaluated by Hematoxylin & Eosin (H&E) staining. To test the effects of TADIOS on LPS-induced oxidative stress, myeloperoxidase (MPO) activity and the total antioxidant capacity were measured.

RESULTS

TADIOS was prepared by extraction of a blend of these three plants by ethanol, and quality control was performed through quantification of marker compounds by HPLC and measurement of bioactivities using cell-based bioassays. In the murine macrophage cell line RAW264.7, TADIOS effectively suppressed the production of pro-inflammatory cytokines such as IL-6 and IL-1β, and also ROS induced by LPS. When RAW264.7 cells were transfected with a luciferase reporter plasmid containing nucleotide sequences for AREs, TADIOS treatment increased the level of relative luciferase units in a dose-dependent manner. In the LPS-induced acute lung injury mouse model, orally administered TADIOS alleviated lung damage and neutrophil infiltration induced by LPS. Consistent with the in vitro data, treatment with TADIOS inhibited the LPS-mediated expression of pro-inflammatory cytokines and oxidative stress, and activated the Nrf2-HO-1 axis.

CONCLUSION

Our data suggest the potential for TADIOS to be developed as a safe and effective therapeutics for the treatment of acute respiratory distress syndrome.

BRD4 targeting nanotherapy prevents lipopolysaccharide induced acute respiratory distress syndrome

Acute respiratory distress syndrome (ARDS) is a life threatening respiratory disease associated with pulmonary edema, alveolar dysfunction, hypoxia, and inflammatory cell accumulation. The most contagious form of COVID-19 associated with ARDS caused by SARS-CoV-2. SARS-CoV-2 majorly produces the cytokine storm and severe lung inflammation and ultimately leads to respiratory failure. ARDS is a complex disease and there is no proper therapeutics for effective therapy. Still, there is a huge scope to identify novel targets to combat respiratory illness. In the current study, we have identified the epigenetic regulating protein BRD4 and developed siRNA based nanomedicine to treat the ARDS. The liposomes were prepared by thin-film hydration method, where BRD4 siRNA complexed with cationic lipid and exhibited 96.24 ± 18.01 nm size and stable even in the presence of RNase. BRD4 siRNA lipoplexes (BRD4-siRNA-LP) inhibited inflammatory cells in lungs and suppressed the lipopolysaccharide (LPS) induced the neutrophil infiltration and mast cell accumulation. Also, BRD4 siRNA based nanomedicine significantly reduced the LPS induced cytokine storm followed by inflammatory signaling pathways. Interestingly, BRD4-siRNA-LP suppressed the LPS-induced p65 and STAT3 nuclear translocation and ameliorated the lung inflammation. Thus, BRD4-siRNA-LP could be a plausible therapeutic option for treating ARDS and might be useful for combating the COVID-19 associated respiratory illness.

P, Biatris PS, J. SJUC. Therapeutic role of corticosteroids in COVID-19: a systematic review of registered clinical trials

BACKGROUND

In March 2020, the World Health Organization declared the coronavirus disease 2019 as a global pandemic. Though antiviral drugs and antimalarial drugs are considered treatment options for treating coronavirus disease 2019 (COVID-19), no specific antivirals are currently available for its treatment. Efficient use of drug discovery approaches including repurposing or repositioning of drugs used in the treatment of severe acute respiratory syndrome coronavirus (SARS-CoV) and the Middle East respiratory syndrome coronavirus (MERS-CoV) is considered recently. The widespread application of corticosteroid therapy in COVID-19 should be backed with careful documented pragmatic research of its use in this context.

MAIN BODY

This article aims to analyze various trials registered across the globe providing an overall picture of the use of corticosteroids in the treatment of COVID-19. An extensive search was conducted on the clinical trial registries around the world to identify all the trials reporting information regarding the use of corticosteroids in COVID-19. Our initial search returned 231 trials, out of which 60 trials were finally included in the analysis. Fifty-six studies were interventional trials, and all the trials had clearly defined primary and secondary outcomes of interest, of which only 11 trials had evaluation of respiratory rate as one of their outcomes.

CONCLUSION

Few preliminary trial findings show promising results and recommend the use of methylprednisolone and dexamethasone in the severe form of the disease; however, there is insufficient data to prove its benefits over its risks. Routine use of corticosteroids should be favored only after a better insight is obtained, with the completion of these trials.

A Review of the Evidence for Corticosteroids in COVID-19

OBJECTIVE

To review available evidence on corticosteroids in acute respiratory distress syndrome (ARDS), Coronavirus Disease 2019 (COVID-19), and other viral pneumonias.

DATA SOURCES

A literature search of MEDLINE, PubMed and clinicaltrials.gov was performed to identify studies between 1980 to 2020 using the following search terms: corticosteroids, COVID19, severe respiratory syndrome coronavirus 2 (SARS-CoV-2), Middle East respiratory syndrome-related coronavirus (MERS-CoV), and influenza. Pre-printed articles were also reviewed at medRxiv.org.

DATA ANALYSIS

Corticosteroids were not recommended early in the COVID-19 pandemic outside of the use for concomitant indications (i.e. ARDS, septic shock) as they have been associated with delayed time to viral clearance in other viral pneumonias. A randomized trial showed a mortality benefit with dexamethasone in COVID-19. Guidelines have been updated to include a strong recommendation for their use in COVID-19 in those hospitalized requiring supplemental oxygen or mechanical ventilation.

CONCLUSION

Based on data from available randomized trials, patients that require respiratory support or mechanical ventilation benefit from corticosteroid therapy. Corticosteroids are an inexpensive and readily available therapy that should be standard of care in hospitalized COVID-19 patients requiring respiratory support.

Effectiveness of Glucocorticoids in Acute Respiratory Distress Syndrome: An Umbrella Review

Objectives. Acute respiratory distress syndrome is a very challenging condition that is associated with high morbidity and mortality. This review was intended to evaluate evidence on the effectiveness of glucocorticoid treatment for acute respiratory distress syndrome. Method. A comprehensive search strategy was conducted on PubMed/Medline, Cochrane Library, Science Direct, and LILACS. Data extraction was carried out by two independent reviewers using a customized checklist. The quality of each systematic review was assessed by two independent reviewers using an AMSTAR tool, and the overall quality of evidence was generated with online GRADEpro GDT software for primary and secondary outcomes. Results. The umbrella review included nine systematic reviews and meta-analysis and one narrative review with 8491 participants. The methodological quality of the included studies was moderate-to-high quality. The overall quality of evidence and recommendations varied form high to very low. Conclusion. There is high-to-moderate quality evidence that early low-dose prolonged glucocorticoid therapy reduces mortality in ARDS. However, randomized controlled trials with large sample sizes to address ventilator-free days, the incidence of infection, and other glucocorticoid-associated adverse events are required as the quality of evidence for these secondary outcomes which were low to very low. Registration. This umbrella review was registered in PROSPERO, the International Prospective Register of Systematic Reviews (CRD42019130539).

Sphingosine 1-phosphate in sepsis and beyond: Its role in disease tolerance and host defense and the impact of carrier molecules

Sphingosine 1-phosphate (S1P) is an important immune modulator responsible for physiological cellular responses like lymphocyte development and function, positioning and emigration of T and B cells and cytokine secretion. Recent reports indicate that S1P does not only regulate immunity, but can also protect the function of organs by inducing disease tolerance. S1P also influences the replication of certain pathogens, and sphingolipids are also involved in pathogen recognition and killing. Certain carrier molecules for S1P like serum albumin and high density lipoproteins contribute to the regulation of S1P effects. They are able to associate with S1P and modulate its signaling properties. Similar to S1P, both carrier molecules are also decreased in sepsis patients and likely contribute to sepsis pathology and severity. In this review, we will introduce the concept of disease tolerance and the involvement of S1P. We will also discuss the contribution of S1P and its precursor sphingosine to host defense mechanisms against pathogens. Finally, we will summarize current data demonstrating the influence of carrier molecules for differential S1P signaling. The presented data may lead to new strategies for the prevention and containment of sepsis.

Pharmacological Agents Targeting Thromboinflammation in COVID-19: Review and Implications for Future Research

Coronavirus disease 2019 (COVID-19), currently a worldwide pandemic, is a viral illness caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). The suspected contribution of thrombotic events to morbidity and mortality in COVID-19 patients has prompted a search for novel potential options for preventing COVID-19-associated thrombotic disease. In this article by the Global COVID-19 Thrombosis Collaborative Group, we describe novel dosing approaches for commonly used antithrombotic agents (especially heparin-based regimens) and the potential use of less widely used antithrombotic drugs in the absence of confirmed thrombosis. Although these therapies may have direct antithrombotic effects, other mechanisms of action, including anti-inflammatory or antiviral effects, have been postulated. Based on survey results from this group of authors, we suggest research priorities for specific agents and subgroups of patients with COVID-19. Further, we review other agents, including immunomodulators, that may have antithrombotic properties. It is our hope that the present document will encourage and stimulate future prospective studies and randomized trials to study the safety, efficacy, and optimal use of these agents for prevention or management of thrombosis in COVID-19.

Clinical features and short-term outcomes of 221 patients with COVID-19 in Wuhan, China

BACKGROUND

In late December 2019, an outbreak of acute respiratory illness, coronavirus disease 2019 (COVID-19), emerged in Wuhan, China. We aimed to study the epidemiology, clinical features and short-term outcomes of patients with COVID-19 in Wuhan, China.

METHODS

We performed a single center, retrospective case series study in 221 patients with laboratory confirmed SARS-CoV-2 pneumonia at a university hospital, including 55 severe patients and 166 non-severe patients, from January 2, 2020 to February 10, 2020.

RESULTS

Of the 221 patients with COVID-19, the median age was 55.0 years and 48.9% were male and only 8 (3.6%) patients had a history of exposure to the Huanan Seafood Market. Compared to the non-severe pneumonia patients, the median age of the severe patients was significantly older, and they were more likely to have chronic comorbidities. Most common symptoms in severe patients were high fever, anorexia and dyspnea. On admission, 33.0% patients showed leukopenia and 73.8% showed lymphopenia. In addition, the severe patients suffered a higher rate of co-infections with bacteria or fungus and they were more likely to developing complications. As of February 15, 2020, 19.0% patients had been discharged and 5.4% patients died. 80% of severe cases received ICU (intensive care unit) care, and 52.3% of them transferred to the general wards due to relieved symptoms, and the mortality rate of severe patients in ICU was 20.5%.

CONCLUSIONS

Patients with elder age, chronic comorbidities, blood leukocyte/lymphocyte count, procalcitonin level, co-infection and severe complications might increase the risk of poor clinical outcomes.

Acute respiratory distress syndrome in acute pancreatitis

Development of organ failure is one of the major determinants of mortality in patients with acute pancreatitis (AP). Acute respiratory distress syndrome (ARDS) is an important cause of respiratory failure in AP and is associated with high mortality. Pathogenesis of ARDS in AP is incompletely understood. Release of various cytokines plays an important role in development of ARDS in AP. Increased gut permeability due to various toxins, inflammatory mediators, and pancreatic enzymes potentiates lung injury by gut-lymph-lung axis leading on to increased translocation of bacterial endotoxins. Various scoring systems, serum levels of various cytokines and lung ultrasound have been evaluated for prediction of development of ARDS in AP with varying results. Various drugs have shown encouraging results in prevention of ARDS in animal models but these encouraging results in animal models are yet to be confirmed in clinical studies. There is no specific effective treatment for ARDS. Treatment of sepsis and local complications of AP should be done according to the standard management strategies. Lung protective ventilatory strategies are of paramount importance to improve outcome of patients of AP with ARDS and therefore effective coordination between gastroenterologists and intensivists is needed for effective management of these patients.

Paralytics, Sedation, and Steroids in Acute Respiratory Distress Syndrome

In this article, we discuss the literature behind the use of paralytics, sedation, and steroids in acute respiratory distress syndrome. We explore the controversies and discuss the recommendations for the use of these agents.

Effects of intravenous phosphodiesterase inhibitors and corticosteroids on severe meconium aspiration syndrome

BACKGROUND

Meconium aspiration syndrome (MAS) is a major cause of severe respiratory failure in near- and full-term neonates. Alleviating inflammation is key to successfully treating severe MAS. Phosphodiesterase (PDE) inhibitors are known to play a role in airway smooth muscle relaxation and alveolar inflammation inhibition. This study aimed to investigate the effects of various intravenous (IV) PDE inhibitors and corticosteroids on MAS.

METHODS

MAS was induced in newborn piglets by instilling human meconium in them. The piglets were randomly divided into five groups (n = 5 in each group): (1) control (sham treatment); (2) dexamethasone (Dex) (IV 0.6 mg/kg of dexamethasone); (3) aminophylline (Ami) (IV 6 mg/kg of aminophylline, followed by continuous infusion of 0.5 mg/kg/h of aminophylline; (4) milrinone (Mil) (IV 50 μg/kg of milrinone, followed by continuous infusion of 0.75 μg/kg/h of milrinone); and (5) rolipram (Rol) (IV 0.8 mg/kg of rolipram). The duration of the experimental period was 4 hours.

RESULTS

Compared to the control group, all the four treatment groups revealed better oxygenation 3 hours and more after the start of treatment. The Rol group had a significantly elevated heart beat (p < 0.05) and relatively lower blood pressure compared to the other groups during the first 2 hours of the experiment. The Dex group had significantly lower interleukin (IL)-1β levels in the lung tissue compared to the other groups (p < 0.05) and significantly lower IL-6 levels compared to the Ami and Mil groups (p < 0.05). Lung histology showed slightly less inflammation and atelectasis in the Dex group compared to the other groups, but lung injury scores showed no significant between-group differences.

CONCLUSION

Using IV corticosteroids or any type of PDE inhibitors has some beneficial effects in improving oxygenation in MAS. PDE inhibitors are not superior to IV corticosteroids; in fact, adverse cardiovascular effects occur with the phosphodiesterase type 4 (PDE4) inhibitor. Further investigations are required before using IV corticosteroids and PDE inhibitors in future clinical application.

Guidelines on the management of acute respiratory distress syndrome

The Faculty of Intensive Care Medicine and Intensive Care Society Guideline Development Group have used GRADE methodology to make the following recommendations for the management of adult patients with acute respiratory distress syndrome (ARDS). The British Thoracic Society supports the recommendations in this guideline. Where mechanical ventilation is required, the use of low tidal volumes (<6 ml/kg ideal body weight) and airway pressures (plateau pressure <30 cmH2O) was recommended. For patients with moderate/severe ARDS (PF ratio<20 kPa), prone positioning was recommended for at least 12 hours per day. By contrast, high frequency oscillation was not recommended and it was suggested that inhaled nitric oxide is not used. The use of a conservative fluid management strategy was suggested for all patients, whereas mechanical ventilation with high positive end-expiratory pressure and the use of the neuromuscular blocking agent cisatracurium for 48 hours was suggested for patients with ARDS with ratio of arterial oxygen partial pressure to fractional inspired oxygen (PF) ratios less than or equal to 27 and 20 kPa, respectively. Extracorporeal membrane oxygenation was suggested as an adjunct to protective mechanical ventilation for patients with very severe ARDS. In the absence of adequate evidence, research recommendations were made for the use of corticosteroids and extracorporeal carbon dioxide removal.

Pretreatment of ferulic acid attenuates inflammation and oxidative stress in a rat model of lipopolysaccharide-induced acute respiratory distress syndrome

Acute respiratory distress syndrome (ARDS) is a fatal clinical condition that can be caused by pulmonary and non-pulmonary diseases. Oxidative stress and inflammation play key roles in the development of ARDS. In this study, we investigated whether ferulic acid (FA), an anti-oxidant, was beneficial for prophylaxis of ARDS. We established an ARDS rat model using lipopolysaccharide (LPS) administration. Lung injury was assessed by lung wet/dry ratio and broncho-alveolar lavage fluid (BALF) analysis. Hematoxylin and eosin staining was performed to evaluate the histological changes of the lungs. Enzyme-linked immunosorbent assay (ELISA) and immunoblotting were performed to detect proteins in BALF and lung tissue, respectively. Pulmonary function was determined by testing the oxygen level in BALF. FA pretreatment significantly alleviated LPS-induced pulmonary histological changes. FA reversed LPS-induced changes of lung wet/dry ratio, total protein in BALF, P(A-a)O₂, and PaO₂/FiO₂. In addition, LPS dramatically up-regulated the secretion of interleukin (IL)-1β, IL-6, tumor necrosis factor (TNF)-α, and IL-10 in BALF (P < 0.01). However, pretreatment of FA significantly improved LPS-induced inflammation. We found that FA indeed reduced oxidative stress in the lungs by testing malondialdehyde level, myeloperoxidase level, and total anti-oxidant capacity. We also proved that FA inactivated multiple mitogen-activated protein kinase signaling pathways in the lungs. In conclusion, FA alleviated LPS-induced ARDS through its anti-inflammatory and anti-oxidant activities.

New Insights into the Immune Molecular Regulation of the Pathogenesis of Acute Respiratory Distress Syndrome

Acute respiratory distress syndrome is an inflammatory disease characterized by dysfunction of pulmonary epithelial and capillary endothelial cells, infiltration of alveolar macrophages and neutrophils, cell apoptosis, necroptosis, NETosis, and fibrosis. Inflammatory responses have key effects on every phase of acute respiratory distress syndrome. The severe inflammatory cascades impaired the regulation of vascular endothelial barrier and vascular permeability. Therefore, understanding the relationship between the molecular regulation of immune cells and the pulmonary microenvironment is critical for disease management. This article reviews the current clinical and basic research on the pathogenesis of acute respiratory distress syndrome, including information on the microenvironment, vascular endothelial barrier and immune mechanisms, to offer a strong foundation for developing therapeutic interventions.

Synthesis and evaluation of 2-cyano-3, 12-dioxooleana-1, 9(11)-en-28-oate-13β, 28-olide as a potent anti-inflammatory agent for intervention of LPS-induced acute lung injury

The present study was designed to synthesize 2-Cyano-3, 12-dioxooleana-1, 9(11)-en-28-oate-13β, 28-olide (1), a lactone derivative of oleanolic acid (OA) and evaluate its anti-inflammatory activity. Compound 1 significantly diminished nitric oxide (NO) production and down-regulated the mRNA expression of iNOS, COX-2, IL-6, IL-1β, and TNF-α in lipopolysaccharide (LPS)-stimulated RAW264.7 cells. Further in vivo studies in murine model of LPS-induced acute lung injury (ALI) showed that 1 possessed more potent protective effects than the well-known anti-inflammatory drug dexamethasone by inhibiting myeloperoxidase (MPO) activity, reducing total cells and neutrophils, and suppressing inflammatory cytokines expression, and thus ameliorating the histopathological conditions of the injured lung tissue. In conclusion, compound 1 could be developed as a promising anti-inflammatory agent for intervention of LPS-induced ALI.

Phototherapy in systemic sclerosis: Review

Systemic scleroderma-also known as systemic sclerosis (SSc)-is a chronic systemic connective tissue disease characterized by collagen deposition in cutaneous and internal organs, leading to skin sclerosis and multiple organ fibrosis. The pathogenesis is complex and remains poorly understood. Treatment is based on organ involvement and requires a multidisciplinary approach. Skin sclerosis can cause disability, leading to decreasing quality of life. Various systemic antifibrotic therapies have been used; however, most have unsatisfactory results. Recently, phototherapy and in particular ultraviolet A (UVA) has been used to treat skin sclerosis in SSc patients with satisfactory results. The main mechanisms include lymphocyte apoptosis, cytokine alteration, inhibition of collagen synthesis and increased collagenase production, and neovascularization, leading to the breakdown of collagen fibrils resulting in skin softening or even healing digital ulcers. Most studies reported that psoralen plus UVA (PUVA) and UVA1 phototherapy improved clinical outcomes vis-à-vis skin sclerosis, joint mobility, ulcers, and histopathology. PUVA and UVA1 phototherapy therefore have potential as an alternative or adjunctive therapy for patients with SSc.

Glucocorticoids limit acute lung inflammation in concert with inflammatory stimuli by induction of SphK1

Acute lung injury (ALI) is a severe inflammatory disease for which no specific treatment exists. As glucocorticoids have potent immunosuppressive effects, their application in ALI is currently being tested in clinical trials. However, the benefits of this type of regimen remain unclear. Here we identify a mechanism of glucocorticoid action that challenges the long-standing dogma of cytokine repression by the glucocorticoid receptor. Contrarily, synergistic gene induction of sphingosine kinase 1 (SphK1) by glucocorticoids and pro-inflammatory stimuli via the glucocorticoid receptor in macrophages increases circulating sphingosine 1-phosphate levels, which proves essential for the inhibition of inflammation. Chemical or genetic inhibition of SphK1 abrogates the therapeutic effects of glucocorticoids. Inflammatory p38 MAPK- and mitogen- and stress-activated protein kinase 1 (MSK1)-dependent pathways cooperate with glucocorticoids to upregulate SphK1 expression. Our findings support a critical role for SphK1 induction in the suppression of lung inflammation by glucocorticoids, and therefore provide rationales for effective anti-inflammatory therapies.

Endothelial damage is a major component of acute lung injury pathogenesis. Here the authors show that in a mouse model of acute lung injury, glucocorticoids induce sphingosine kinase 1 production in macrophages, promoting endothelial barrier function and ameliorating the disease.

Pro-oxidative toxicity of cells in suspension does not point to a cell cultural artefact as an explanation of the increased susceptibility of alveolar epithelial-like cells after glucocorticoid pretreatment

The influence of cell numbers on peroxide-(tertiary butylhydroperoxide (tBHP) or hydrogen peroxide-(HP)) or zinc-(zinc chloride) induced oxidative stress was assessed in alveolar epithelial-like cell lines in this work. Differences in cell numbers change the cellular glutathione and glutathione reductase activity as well as the amount of exported glutathione and therefore might influence susceptibility against oxidative stress. Toxicity due to zinc decreased, toxicity due to HP increased, while tBHP-mediated toxicity was unchanged in our experiments when cells were exposed in suspension as compared to monolayers. Toxicity of HP correlated to the glutathione content in monolayers and in cell suspensions, while zinc- or tBHP-mediated toxicity did not correlate towards glutathione. Decreasing cellular glutathione and the activity of some antioxidative enzymes by glucocorticoid pretreatment had no effect on toxicity of zinc or tBHP in L2 cells in suspensions, while toxicity in monolayers was increased. Glucocorticoid pretreatment seems to increase toxicity of HP in A549 monolayers according to the lowered protein content, while toxicity might be changed by a different way when cells are incubated as cell suspensions. No explanation as a cell culture artificial effect was observed, therefore we assume the increased toxicity after glucocorticoid pretreatment occurs in vivo as well.

Presumptive acute lung injury following multiple surgeries in a cat

A 12-year-old, 3.5-kg spayed female domestic shorthair cat had a tracheal mass identified as malignant B-cell lymphoma. The cat had tracheal resection and subsequently developed laryngeal paralysis. Due to multiple episodes of respiratory distress the cat subsequently had tracheal surgeries. Finally, the cat had a sudden onset of severe respiratory distress and collapsed. Computed tomography imaging and arterial blood gas analysis supported a diagnosis of acute lung injury.

A TLR4-interacting SPA4 peptide inhibits LPS-induced lung inflammation

The interaction between surfactant protein-A (SP-A) and TLR4 is important for host defense. We have recently identified an SPA4 peptide region from the interface of SP-A-TLR4 complex. Here, we studied the involvement of the SPA4 peptide region in SP-A-TLR4 interaction using a two-hybrid system, and biological effects of SPA4 peptide in cell systems and a mouse model. HEK293 cells were transfected with plasmid DNAs encoding SP-A or a SP-A-mutant lacking SPA4 peptide region and TLR4. Luciferase activity was measured as the end-point of SP-A-TLR4 interaction. NF-κB activity was also assessed simultaneously. Next, the dendritic cells or mice were challenged with Escherichia coli-derived LPS and treated with SPA4 peptide. Endotoxic shock-like symptoms and inflammatory parameters (TNF-α, NF-κB, leukocyte influx) were assessed. Our results reveal that the SPA4 peptide region contributes to the SP-A-TLR4 interaction and inhibits the LPS-induced NF-κB activity and TNF-α. We also observed that the SPA4 peptide inhibits LPS-induced expression of TNF-α, nuclear localization of NF-κB-p65 and cell influx, and alleviates the endotoxic shock-like symptoms in a mouse model. Our results suggest that the anti-inflammatory activity of the SPA4 peptide through its binding to TLR4 can be of therapeutic benefit.

Mesenchymal stem cells: a promising therapy for the acute respiratory distress syndrome

Acute respiratory distress syndrome (ARDS) is a pulmonary syndrome with growing prevalence and high mortality and morbidity that increase with age. There is no current therapy able to restore pulmonary function in ARDS patients. Preclinical models of ARDS have demonstrated that intratracheal or systemic administration of mesenchymal stem cells (MSCs) protects the lung against injury. The mechanisms responsible for the protective effects are multiple, including the secretion of multiple paracrine factors capable of modulating the immune response and restoring epithelial and endothelial integrity. Recent studies have demonstrated that MSCs can also control oxidative stress, transfer functional mitochondria to the damaged cells, and control bacterial infection by secretion of antibacterial peptides. These characteristics make MSCs promising candidates for ARDS therapy.

Ccl2/Cx3cr1-deficient mice: an animal model for age-related macular degeneration

BACKGROUND/AIMS

Senescent Ccl2-/- mice develop cardinal features of human age-related macular degeneration (AMD). Loss-of-function single-nucleotide polymorphisms within CX3CR1 are associated with AMD.

METHODS

We generated Ccl2-/-/Cx3cr1-/- [double-knockout (DKO)] mice and evaluated the eyes using fundoscopy routine histology, immunochemistry, biochemistry and proteomics.

RESULTS

At 6 weeks old, all DKO mice developed AMD-like retinal lesions such as abnormal retinal pigment epithelium cells, drusen, photoreceptor atrophy and choroidal neovascularization, which progressed with age and reversed with high omega-3 long-chain polyunsaturated fatty acid diet. N-retinylidene-N-retinylethanolamine (A2E), a major lipofuscin fluorophore, illustrated by an emission peak at approximately 600 nm, was significantly higher in DKO retinal pigment epithelium. Decreased ERp29 was found in the retina of DKO mice.

CONCLUSION

A broad spectrum of AMD pathologies with early onset and high penetrance in these mice implicate certain chemokines, A2E and endoplasmic reticulum proteins in AMD pathogenesis.