Daily Ards Research Analysis
Three impactful studies span mechanism to bedside: a preclinical study shows nootkatone protects against LPS-induced acute lung injury by suppressing the STING/TBK1/IRF3 axis in alveolar macrophages; a U.S. nationwide cohort confirms age is a strong, linear predictor of in-hospital mortality among ARDS patients on VV ECMO, arguing against strict age cutoffs; and an integrative proteomic–metabolomic study in late-pregnancy COVID-19 reveals inflammatory and metabolic pathway disruptions with adver
Summary
Three impactful studies span mechanism to bedside: a preclinical study shows nootkatone protects against LPS-induced acute lung injury by suppressing the STING/TBK1/IRF3 axis in alveolar macrophages; a U.S. nationwide cohort confirms age is a strong, linear predictor of in-hospital mortality among ARDS patients on VV ECMO, arguing against strict age cutoffs; and an integrative proteomic–metabolomic study in late-pregnancy COVID-19 reveals inflammatory and metabolic pathway disruptions with adverse perinatal outcomes.
Research Themes
- Immunometabolic targeting of the STING pathway in ALI/ARDS
- Patient selection and prognostication for VV ECMO in ARDS
- Maternal-fetal inflammatory and metabolic signatures in late-pregnancy COVID-19
Selected Articles
1. Nootkatone immunomodulates alveolar macrophage via STING/TBK1/IRF3 signaling pathway inhibition to protect against LPS-induced acute lung injury.
In LPS-induced ALI, nootkatone reduced inflammatory cell influx and cytokines, reprogrammed lung and alveolar macrophage metabolism toward baseline, and inhibited phospho-STING/TBK1/IRF3 signaling. These data identify the STING pathway in AMs as a druggable axis and support nootkatone as a candidate anti-inflammatory therapy for ALI/ARDS.
Impact: This work uncovers a tractable immunometabolic mechanism—STING/TBK1/IRF3 inhibition in alveolar macrophages—linking to robust in vivo efficacy, offering a credible therapeutic avenue beyond broad immunosuppression.
Clinical Implications: While preclinical, targeting STING signaling in alveolar macrophages may inform the development of precision anti-inflammatory therapies for ALI/ARDS, potentially reducing ventilator-induced injury by enabling lower-intensity support.
Key Findings
- Nootkatone lowered total cells, macrophages, and neutrophils in BALF and reduced IL-6, TNF-α, and IL-1β in LPS-induced ALI mice.
- It downregulated inflammatory mediator genes in alveolar macrophages (e.g., Cxcl10, Ccl3, Ccl4, Csf3, Il1b, Ccl5).
- It blunted mitochondrial respiration and glycolysis in lung single cells and AMs, approaching baseline metabolic activity.
- It significantly inhibited phospho-STING, phospho-TBK1, and phospho-IRF3 in lungs and AMs, implicating the STING/TBK1/IRF3 axis.
Methodological Strengths
- In vivo ALI model with complementary cellular (alveolar macrophage) analyses.
- Multi-layer readouts (cytokines, gene expression, metabolism, signaling proteins) supporting a coherent mechanism.
Limitations
- Preclinical models may not recapitulate human ARDS heterogeneity.
- Dose–response, pharmacokinetics, and safety in large animals/humans were not addressed.
Future Directions: Validate efficacy across ARDS phenotypes and pathogens, define optimal dosing and PK/PD, and assess combination strategies with ventilatory/ECMO support in translational models.
Acute lung injury (ALI) and acute respiratory distress syndrome (ARDS) are characterized by diffuse pulmonary interstitial edema, alveolar edema, lung infiltration by immune cells, and acute hypoxic respiratory insufficiency. Nootkatone (NKT) is an organic compound and a bioactive sesquiterpene ketone with anti-inflammatory properties. This study aims to explore the potential protective effects of NKT in lipopolysaccharide (LPS)-induced ALI models. The study assesses the anti-inflammatory action of NKT, its effects on the metabolism of both the lungs and alveolar macrophages (AMs), and the underlying cellular mechanisms. NKT inhibits the increase in total cell, macrophage and neutrophil counts in bronchoalveolar lavage fluid of the ALI mice, as well as pro-inflammatory cytokines (IL-6, TNF-α, and IL-1β). NKT also downregulates the expressions of genes related to inflammatory mediator in AMs, including Cxcl10 (IP-10), Ccl4 (MIP-1β), Ccl3 (MIP-1α), Csf3 (G-CSF), Il22 (IL-22), Il12a (IL-12α), Il1b (IL-1β), Ccl5 (RANTES). NKT diminishes mitochondrial respiration and glycolysis in lung single cells and AMs of ALI mice almost to baseline. Treatment with NKT significantly reduces the protein expression of phospho-STING, phospho-TANK-binding kinase 1 (TBK1) and phospho-IFN regulatory factor 3 (IRF3) in the lungs and AMs, thereby inhibiting the STING/TBK1/IRF3 pathway. We report for the first time that NKT may exert its anti-inflammatory effects in LPS-induced ALI by suppressing the STING/TBK1/IRF3 signaling pathway in AMs and lungs, offering compelling evidence for further development of NKT as a treatment of ALI.
2. Proteomic and metabolomic analysis of serum in women infected with COVID-19 during late pregnancy.
In third-trimester COVID-19, serum DIA-proteomics and metabolomics identified acute-phase protein changes (e.g., SAA1/2) and perturbations in riboflavin, aromatic amino acid, arginine, steroid hormone, and fatty acid pathways. Clinically, the infected group had higher rates of cesarean delivery, postpartum reproductive tract infection, and fetal distress.
Impact: This integrative omics study links molecular pathway disruptions to adverse perinatal outcomes in late-pregnancy COVID-19, providing candidate biomarkers and targets for maternal–fetal risk stratification.
Clinical Implications: Serum proteo-metabolomic signatures could inform risk stratification and monitoring in pregnant patients with COVID-19, motivating targeted obstetric and infectious disease management.
Key Findings
- Higher rates of cesarean section, postpartum reproductive tract infection, and fetal distress in the COVID-19 group versus controls.
- Proteomic changes included regulation of SAA1, SAA2, IPO7, WDR19, and BAZ1A, linked to developmental processes.
- Metabolomic alterations implicated riboflavin metabolism, phenylalanine/tyrosine/tryptophan biosynthesis, and arginine biosynthesis; integrated analysis highlighted disruptions in steroid hormone biosynthesis and fatty acid degradation.
Methodological Strengths
- Combined DIA-proteomics and UPLC-Q-TOF-MS metabolomics with pathway enrichment analysis.
- Time-anchored sampling (within 2 days of fever onset vs 1 week pre-delivery) enabling biologically meaningful contrasts.
Limitations
- Single-center, small sample size limits generalizability and statistical power.
- Cross-sectional design precludes causal inference and longitudinal trajectory mapping.
Future Directions: Validate biomarkers in multicenter cohorts, integrate placental/cord blood omics, and link maternal signatures to neonatal outcomes longitudinally.
INTRODUCTION: To investigate the alterations of serum proteins and metabolomics in women infected with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) at the end of pregnancy and their potential effects on fetal development. METHODS: The corona virus disease 2019 (COVID-19) group (n=31) included women in the third trimester diagnosed with SARS-CoV-2 infection and who delivered, while the control group (n=30) comprised uninfected women in the same gestational period. This study applied data-independent acquisition (DIA) proteomics and ultra-performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry (UPLC-Q-TOF-MS) metabolomics to analyze serum samples from two groups of full-term pregnant women. Serum samples in the control group were collected one week before delivery, while those in the COVID-19 group were collected within two days after the onset of fever. The differences between groups were compared by bioinformatics data analysis. For proteins and metabolites exhibiting a significant association with SARS-CoV-2, metabolic pathway enrichment was performed utilizing MetaboAnalyst 6.0, and the possible targets and pathways of SARS-CoV-2 infection in women in late pregnancy were plotted. RESULTS: The incidence of cesarean section, postpartum reproductive tract infection, and fetal distress were significantly higher in the COVID-19 group compared to the control group. Differential proteomic analysis revealed the regulation of proteins such as SAA1, SAA2, IPO7, WDR19, and BAZ1A, which were involved in processes such as visual, skin and limb development. Metabolomics analysis revealed key altered metabolites, including 1-(7-methoxy-2-oxo-2H-chromen-8-yl)-3-methyl-2-oxobutylacetate, 5-(hydroxymethyl) -4-methoxy-2,5-dihydrofuran-2-one, and cyclocytidine, which were involved in the riboflavin metabolism, the phenylalanine, tyrosine and tryptophan biosynthesis, and the arginine biosynthesis. Integrative analysis of proteomic and metabolomic revealed significant disruptions in metabolic pathways, including arginine biosynthesis, steroid hormone biosynthesis, and fatty acid degradation. CONCLUSIONS: This study revealed the main proteomic and metabolic effects of SARS-CoV-2 infection on women in the third trimester of pregnancy. Our comprehensive omics data elucidating the molecular mechanisms underlying SARS-CoV-2 infection in women during late pregnancy. These findings offer novel insights and potential targets for future investigations into the impact of SARS-CoV-2 infection on maternal and infant health.
3. Age and In-Hospital Mortality in Patients With Acute Respiratory Distress Syndrome Undergoing Venovenous Extracorporeal Membrane Oxygenation.
Using a large U.S. inpatient database, mortality among ARDS patients on VV ECMO rose linearly with age without a clear threshold, with ORs reaching 4.27 for ≥76 vs 18–25 years. The authors recommend individualized ECMO candidacy based on overall clinical status rather than strict age cutoffs.
Impact: Clarifies the age–mortality relationship in ECMO-supported ARDS at scale, informing ethical and operational decisions about patient selection during resource-constrained conditions.
Clinical Implications: Avoid rigid age cutoffs for VV ECMO in ARDS; integrate age as a continuous risk factor within comprehensive assessments (comorbidities, trajectory, frailty) when determining candidacy.
Key Findings
- Among 510,175 ARDS hospitalizations, 13,150 received VV ECMO with a 43.4% in-hospital mortality rate.
- Predicted mortality increased linearly with age; mortality ORs vs 18–25 years: 26–35 (1.01), 36–45 (1.47), 46–55 (1.96), 56–65 (2.79), 66–75 (3.72), ≥76 (4.27).
- No clear age threshold was identified, arguing against strict age-based exclusion for ECMO.
Methodological Strengths
- Large, nationally representative inpatient sample with multivariable adjustment.
- Age modeled across categories demonstrating a consistent linear trend.
Limitations
- Retrospective administrative data lack granular physiologic and ventilatory parameters.
- Residual confounding and selection bias in ECMO referral/availability cannot be excluded.
Future Directions: Incorporate physiologic severity scores, frailty, and trajectory data into predictive models and validate in prospective registries to refine ECMO candidacy tools.
Age is a known risk factor for mortality in acute respiratory distress syndrome (ARDS) patients receiving venovenous extracorporeal membrane oxygenation (VV ECMO), but an optimal age cutoff for patient selection remains unclear. This study evaluates the association between age and in-hospital mortality in ARDS patients undergoing VV ECMO using the National Inpatient Sample from 2019 to 2022. We included adults with ARDS treated with VV ECMO and applied logistic regression to assess mortality risk while adjusting for demographics, comorbidities, hospital settings, and socioeconomic factors. Among an estimated 510,175 ARDS hospitalizations, 13,150 patients received VV ECMO, with an in-hospital mortality rate of 43.4%. The predicted mortality increased linearly with age. Compared with patients aged 18-25 years, the odds ratios (ORs) for mortality were 1.01 (26-35 years), 1.47 (36-45 years), 1.96 (46-55 years), 2.79 (56-65 years), 3.72 (66-75 years), and 4.27 (≥76 years), with statistical significance for older groups. Our findings confirm age as a strong predictor of mortality in this population. However, the absence of a clear threshold suggests that strict age cutoffs may not be justified. Instead, ECMO candidacy should be individualized, emphasizing overall clinical status rather than age alone.