Daily Ards Research Analysis
Analyzed 5 papers and selected 3 impactful papers.
Summary
Mechanistic studies identify the NLRP3 inflammasome and NF-κB/TSPO axis as actionable pathways to mitigate lung inflammation in preclinical ARDS models, while human immunoprofiling shows XBB.1.5 monovalent boosters preferentially enhance Omicron-lineage immunity under immune imprinting constraints. Together, these findings chart translational paths for host-targeted ARDS interventions and inform variant-updated vaccine strategies.
Research Themes
- Inflammasome-targeted therapeutics for ARDS
- Sedative repurposing via NF-κB/TSPO modulation in lung injury
- Immune imprinting and variant-updated SARS-CoV-2 vaccination
Selected Articles
1. Nimbolide ameliorates ARDS and ulcerative colitis by disrupting NLRP3 inflammasome activation.
A natural product screen identified nimbolide as a selective NLRP3 inflammasome inhibitor that blocks both NF-κB-dependent priming and inflammasome assembly by targeting Lys565 in the NLRP3 NACHT domain. In LPS-induced ARDS and DSS colitis mouse models, nimbolide reduced inflammation and tissue injury, supporting a dual-modulatory strategy for NLRP3-driven diseases.
Impact: This study discovers a selective, dual-phase NLRP3 inhibitor with target-site mapping and in vivo efficacy in ARDS models, addressing a long-standing translational gap in inflammasome therapeutics.
Clinical Implications: Provides a mechanistic basis for developing NLRP3-targeted therapies for ARDS and other inflammatory disorders; translation will require PK/PD, safety, and efficacy studies in larger animal models and early-phase trials.
Key Findings
- Nimbolide dose-dependently suppresses NLRP3 activation, blocking Caspase-1 cleavage, IL-1β release, and pyroptosis in macrophages.
- Nimbolide selectively targets NLRP3, with no significant inhibition of non-NLRP3 inflammasomes.
- Mechanistically, nimbolide inhibits both NF-κB-dependent priming and inflammasome assembly by targeting Lys565 in the NLRP3 NACHT domain.
- In vivo, nimbolide alleviates inflammation and tissue damage in LPS-induced ARDS and DSS-induced colitis in mice, supported by Nlrp3-knockout models.
Methodological Strengths
- Integrated approach from natural product library screening to mechanistic target-site mapping and selectivity testing.
- Validation across cellular systems and in vivo models, including Nlrp3-knockout mice.
Limitations
- Preclinical evidence limited to murine models; human safety, PK/PD, and efficacy are unknown.
- Dosing, exposure-response relationships, and off-target liabilities were not fully characterized.
Future Directions: Define PK/PD and safety, resolve structural binding via biophysics/crystallography, and test efficacy in diverse ARDS etiologies (e.g., sepsis, viral) followed by phase I studies.
Excessive activation of the NLRP3 inflammasome drives the pathogenesis of diverse inflammatory diseases. However, the clinical application of NLRP3 inflammasome inhibitors remains a significant challenge. Here, we screen a natural product library of 126 compounds and identify Nimbolide (NIM), a triterpenoid from Azadirachta indica, as a potent suppressor of IL-1β secretion. Cellular studies reveal that NIM dose-dependently suppresses NLRP3 inflammasome activation, thereby the blocking Caspase-1 cleavage, IL-1β release, and pyroptosis in macrophages. Importantly, NIM exhibits high selectivity for NLRP3 inflammasome, showing no significant inhibition of non-NLRP3 inflammasomes. Mechanistically, NIM exerts dual effects by suppressing both NF-κB-dependent priming and NLRP3 inflammasome assembly. Molecular investigations reveal that NIM directly targets the Lys565 within the NLRP3 NACHT domain, thereby hindering inflammasome assembly. Using male C57BL/6 and Nlrp3-knockout mice, we demonstrate that NIM administration effectively alleviates inflammation and pathological damage in models of LPS-induced acute respiratory distress syndrome (ARDS) and DSS-induced ulcerative colitis. Collectively, our findings highlight NIM as a natural inhibitor that targets both the priming and assembly phases of NLRP3 inflammasome activation, offering a dual-modulatory strategy for treating NLRP3-driven inflammatory disorder.
2. Preferential boosting of SARS-CoV-2 Omicron lineage-specific immune responses by monovalent XBB.1.5 vaccination.
In healthcare workers, monovalent XBB.1.5 vaccination preferentially boosted neutralizing and functional antibody responses to circulating Omicron subvariants while maintaining lower titers than those to ancestral spike. Vaccination recalled broadly S-reactive B cells with limited de novo XBB.1.5-specific clones, and T-cell responses remained broadly cross-reactive.
Impact: Comprehensive longitudinal immune profiling clarifies how variant-updated boosters reshape humoral and cellular immunity under immune imprinting, informing booster design and expectations of protection.
Clinical Implications: Supports use of monovalent variant boosters to enhance recognition of circulating Omicron lineages while highlighting persistent imprinting; vaccine updates may need strategies to elicit de novo variant-specific B-cell responses.
Key Findings
- Neutralizing antibodies to circulating Omicron subvariants were preferentially boosted but remained below titers against ancestral spike.
- Antibodies mediating ADCC were also boosted and showed broader promiscuity.
- Vaccination recalled broadly S-reactive B cells with limited de novo induction of XBB.1.5-specific B-cell clones.
- T-cell responses cross-reacted with all assessed SARS-CoV-2 variants.
Methodological Strengths
- Longitudinal profiling up to 6 months with integrated assessment of neutralization, ADCC, and B/T-cell phenotypes.
- Focus on real-world healthcare workers with diverse exposure histories to vaccination and infection.
Limitations
- Sample size and detailed exposure stratification are not specified in the abstract; cohort limited to healthcare workers.
- No direct clinical endpoints (e.g., infection incidence or severity) reported.
Future Directions: Quantify correlates of protection across variants, optimize antigen design to overcome imprinting, and link immune profiles to clinical effectiveness in diverse populations.
OBJECTIVES: Ongoing escape from pre-existing antibodies by severe acute respiratory distress syndrome coronavirus-2 (SARS-CoV-2) necessitates yearly coronavirus disease 2019 (COVID-19) vaccine updates. Monovalent variant-specific booster vaccines for at-risk populations aim to re-direct antibody responses towards antigenically distinct variants. However, multiple past exposures to the ancestral SARS-CoV-2 spike (S) protein through vaccination and infection could hinder the de novo induction of variant-specific immune responses. METHODS: Here, we profiled SARS-CoV-2-specific antibody, T- and B-cell immune responses in healthcare workers up to 6 months after monovalent XBB.1.5 vaccination. RESULTS: Neutralizing antibodies targeting Omicron subvariants circulating at the time of vaccination were preferentially boosted by vaccination but remained lower than those neutralizing the ancestral strain. Similar responses were observed for antibodies that mediate functionality through antibody-dependent cellular cytotoxicity, although these responses were more promiscuous. Broadly S-reactive B-cells were recalled by vaccination, with limited de novo induction of XBB.1.5-specific B-cell clones. B-cells targeting the receptor binding domain of circulating Omicron subvariants were favored, and T-cell responses cross-reacted with all SARS-CoV-2 variants that were assessed. CONCLUSIONS: Combined, this comprehensive immune profiling demonstrates that despite evidence of imprinted antibody responses targeting ancestral S, monovalent booster vaccination skews the immune response to Omicron lineage recognition.
3. Remimazolam alleviates acute lung injury via translocator protein mediated inhibition of the NF-κB pathway.
Remimazolam attenuated LPS-induced ALI by inhibiting NF-κB signaling via translocator protein, reducing cytokine production and preserving endothelial/epithelial junctions in mice and cell models. Pharmacologic perturbations with an NF-κB agonist and a TSPO ligand corroborated the mechanism.
Impact: Identifies an approved sedative with anti-inflammatory and barrier-protective actions mediated through TSPO/NF-κB, supporting drug repurposing prospects for ARDS.
Clinical Implications: Suggests remimazolam may offer dual benefits—sedation and anti-inflammatory barrier protection—in ARDS/ALI; warrants dose-finding, safety, and efficacy evaluation in clinically relevant ARDS settings.
Key Findings
- Remimazolam reduced neutrophil infiltration and pro-inflammatory cytokine production in LPS-induced ALI.
- Network pharmacology and RNA-seq implicated NF-κB signaling; remimazolam inhibited IKB-α phosphorylation in endothelial and epithelial cells and in murine lungs.
- NF-κB agonist PMA abrogated remimazolam’s effects, while a selective TSPO ligand reversed its inhibition of IKB-α phosphorylation and inflammatory responses, implicating TSPO.
Methodological Strengths
- Convergent in vivo and in vitro validation with mechanistic readouts (RNA-seq, signaling assays).
- Use of pharmacologic agonist/antagonist tools to causally implicate NF-κB and TSPO.
Limitations
- Preclinical LPS-induced model may not capture full ARDS heterogeneity; no survival or lung mechanics outcomes reported.
- Translational dosing relative to clinical sedation regimens and safety endpoints are not addressed.
Future Directions: Evaluate efficacy across infectious and sterile ARDS etiologies, define sedative-exposure windows that maximize anti-inflammatory benefits, and initiate early-phase clinical studies.
BACKGROUND: Acute lung injury (ALI)/acute respiratory distress syndrome (ARDS) is characterized by inflammatory dysregulation and alveolar-capillary barrier damage, leading to high mortality. Remimazolam (REM), an ultra-short-acting benzodiazepine, shows anti-inflammatory effects preclinically; however, its therapeutic role and mechanism in ALI/ARDS remain unclear. This study aimed to explore the mechanism underlying the effects of REM against ALI/ARDS. METHODS: An ALI model was established by lipopolysaccharide (LPS) challenge in mice to evaluate REM's efficacy. Then, network pharmacology and RNA sequencing were performed to identify the potential mechanism on REM against ALI/ARDS, which were further validated using LPS-stimulated human umbilical vein endothelial cells, murine lung epithelial cells, and ALI murine model. RESULTS: REM significantly attenuated neutrophil infiltration in the lungs of ALI mice. Integrated network pharmacology and RNA sequencing analyses revealed that the targets of REM in ALI/ARDS were significantly enriched in the regulation of inflammatory responses, cellular junctions, and the NF-κB pathway. In vivo and in vitro experiments confirmed that REM suppressed LPS-induced pro-inflammatory cytokine production and preserved inter-endothelial/epithelial junction integrity. Moreover, REM inhibited LPS-triggered IKB-α phosphorylation in endothelial and alveolar epithelial cells, and ALI murine lung tissues. Crucially, the NF-κB agonist-phorbol 12-myristate 13-acetate abrogated REM's anti-inflammatory and barrier-protective effects. Conversely, the selective translocator protein ligand reversed REM-mediated inhibition of IKB-α phosphorylation and inflammatory responses in both cell lines. CONCLUSION: REM alleviated ALI by suppressing the NF-κB pathway via translocator protein, reducing inflammation and preserving alveolar-capillary barrier function. These findings highlight REM's potential for ARDS treatment.