Sepsis and Acute Respiratory Distress Syndrome: Recent Update

Thrombospondin-1 modulation by Bifidobacterium spp. mitigates lung damage in an acute lung injury mouse model

Our study shows that Bifidobacterium spp. supplementation reduces lung damage in acute lung injury by enhancing immune cell activity and restoring thrombospondin-1 levels, offering a promising therapeutic approach for the treatment of ALI/ARDS.

BACKGROUND

Acute lung injury (ALI) and acute respiratory distress syndrome (ARDS) are critical conditions characterized by severe lung inflammation and damage, often exacerbated by mechanical ventilation. Probiotics, particularly those containing Bifidobacterium spp. (Bifidus) have shown promise in modulating immune responses and reducing inflammation.

METHODS

In this study, we investigated the effects of Bifidus supplementation in a mouse model of lipopolysaccharide induced ALI and ventilator-induced lung injury.

RESULTS

Our results demonstrate that Bifidus significantly ameliorates lung injury by enhancing efferocytosis and reducing pro-inflammatory cytokine levels. Single-cell RNA sequencing revealed significant changes in lung immune cell populations, particularly macrophages and monocytes, which showed increased efferocytosis activity and modulation of key signaling pathways such as TNF, MAPK and TLR. Notably, Bifidus feeding restored thrombospondin-1 levels in lung tissue, facilitating clearance of apoptotic cells and promoting resolution of inflammation.

CONCLUSIONS

Overall, our study highlights the potential of Bifidus as a therapeutic strategy to mitigate lung injury in ALI/ARDS.

Bosutinib mitigates inflammation in experimental sepsis

BACKGROUND

Sepsis, a leading cause of death globally, lacks targeted and effective treatment. Its pathophysiology involves unbalanced inflammation, marked by a high release of inflammatory mediators, leukocyte recruitment, vascular changes and dysfunction of the nervous and respiratory systems. Src family tyrosine kinases (SFK) play a critical role in immune responses, and their inhibition can modulate excessive inflammation. This study investigates the potential of bosutinib, an SFK inhibitor, as a treatment for sepsis.

METHODS

Clinical signs, survival rates, systemic and neuronal inflammatory responses, cell recruitment, lung function and cerebral microcirculation were analysed in mice treated with bosutinib (3 mg/kg) or DMSO/saline followed by cecal ligation and puncture (CLP)-induced sepsis.

RESULTS

Bosutinib treatment reduced the severity of sepsis, improved survival rates and reduced the levels of pro-inflammatory cytokines and chemokines in peritoneal lavage, plasma and brain tissue. It also reduced cellular infiltration and bacterial growth at the infection site and protected lung function by reducing diffuse alveolar damage. Using intravital microscopy and laser speckle techniques, bosutinib improved capillary density and blood perfusion and reduced leukocyte recruitment and adhesion in the cerebral microcirculation of septic animals.

CONCLUSIONS

Bosutinib pretreatment attenuated dysregulated inflammatory responses and neurovascular changes in experimental sepsis.

Pyroptosis of pulmonary fibroblasts and macrophages through NLRC4 inflammasome leads to acute respiratory failure

The NAIP/NLRC4 inflammasome plays a pivotal role in the defense against bacterial infections, with its in vivo physiological function primarily recognized as driving inflammation in immune cells. Acute lung injury (ALI) is a leading cause of mortality in sepsis. In this study, we identify that the NAIP/NLRC4 inflammasome is highly expressed in both macrophages and pulmonary fibroblasts and that pyroptosis of these cells plays a critical role in lung injury. Mice challenged with gram-negative bacteria or flagellin developed lethal lung injury, characterized by reduced blood oxygen saturation, disrupted lung barrier function, and escalated inflammation. Flagellin-induced lung injury was protected in caspase-1 or GSDMD-deficient mice. These findings enhance our understanding of the NAIP/NLRC4 inflammasome's (patho)physiological function and highlight the significant role of inflammasome activation and pyroptosis in ALI during sepsis.

Harnessing stem cell therapeutics in LPS-induced animal models: mechanisms, efficacies, and future directions

The severity and threat posed by inflammation are well documented, and lipopolysaccharides (LPS), as important inducers of inflammatory responses, are widely recognized for studying host immunity and the resulting tissue and organ damage. The LPS-induced disease model, triggers a remarkable release of inflammatory factors, immune and coagulation dysfunction, and damage to vital organs such as the brain, lungs, heart, liver, and kidneys. Recently, the role of mesenchymal stem cells (MSCs) in various clinical diseases has garnered significant attention due to their immunomodulatory, anti-inflammatory, tissue healing, anti-apoptotic, and antibacterial properties. Despite the common use of LPS models to induce disease models and simulate acute inflammation, the integration of stem cell therapy within these models remains underexplored. This article integrates the LPS induced animal model and reviews the current evidence regarding the therapeutic mechanisms of stem cells in LPS-induced disease models across various human body systems. Furthermore, this review predicts and hypothesizes the feasibility and potential of using stem cells in disease models that have not yet been extensively studied, based on existing animal inflammation models.

Heme-induced lung injury in human precision cut lung slices: a new model for acute lung injury

BACKGROUND

Acute respiratory distress syndrome (ARDS) causes high mortality and has no specific pharmacological treatment. Scarcity of drugs against ARDS is in part due to the lack of models for ARDS. As raised serum heme levels are associated with higher mortality in patients with ARDS, we hypothesised that circulating heme contributes to ARDS pathology and can induce lung injury resembling human disease. We aimed to develop a new model for acute lung injury and ARDS research with heme-induced injury in human precision cut lung slices (PCLS).

METHODS

We analysed heme and its degrading enzymes along with inflammatory cytokines in patients with coronavirus disease 2019 (COVID-19) and ARDS compared to healthy adult subjects. In PCLS, we studied effects of heme on cell survival, membrane integrity, the transcriptome by gene expression and the proteome by protein expression analysis or ELISA. We also tested synergistical effects with lipopolysaccharide (LPS) on cell survival in addition to heme to simulate bacterial infection.

RESULTS

Patients with COVID-19 and ARDS had increased serum levels of heme and heme oxygenase 1 (HO-1) compared to controls. In PCLS, heme induced cell death in a dose-dependent manner, stimulated pro-inflammatory and injury signals and triggered changes to the extracellular matrix (ECM). Comparative analyses of the lung transcriptomic and proteomic signatures revealed 27 common markers (log2 fold change greater than 1, at adjusted (adj) p-value < 0.05 significant), most of which were inflammatory. Similar inflammatory cytokines were raised in blood from patients with COVID-19 and ARDS compared to controls. LPS did not increase cytotoxicity in addition to heme.

CONCLUSION

Heme induced inflammatory cytokine release and cell death in human PCLS, resembling the patterns observed in blood samples from patients with COVID-19 and ARDS. Thus, heme-stimulated PCLS represent a novel ex vivo model for mechanistic studies for acute lung injury and ARDS.

Successful management of severe anaerobic infection inducing mediastinal and subcutaneous emphysema, septic shock, and ARDS: a case report highlighting VV-ECMO and NGS-guided therapy

Background

Mediastinal and cervical subcutaneous emphysema caused by anaerobic infections is rare in clinical practice, particularly when accompanied by sepsis, septic shock, and severe acute respiratory distress syndrome (ARDS). These cases pose significant treatment challenges. Veno-venous extracorporeal membrane oxygenation (VV-ECMO), as a life-saving intervention, has been increasingly utilized in patients with severe infections and refractory hypoxemia. This report aims to evaluate the effectiveness of VV-ECMO in the treatment of mediastinal and subcutaneous emphysema, sepsis, and severe ARDS caused by anaerobic infections, and to summarize relevant therapeutic strategies.

Case presentation

A 49-year-old male was admitted with fever, sore throat, chest tightness, and hoarseness. On admission, he presented with severe hypoxemia, sepsis, and acute kidney injury. Chest computed tomography (CT) revealed bilateral mediastinal emphysema and cervical subcutaneous emphysema. Next-generation sequencing (NGS) confirmed an anaerobic bacterial infection. Despite high-flow oxygen therapy and antibiotic treatment, the patient's oxygenation continued to deteriorate, culminating in cardiopulmonary arrest. VV-ECMO was initiated to improve oxygenation, alongside prone positioning ventilation, sputum clearance, and alveolar lavage. After 7 days of ECMO support and anti-infective treatment, the patient's oxygenation improved significantly, inflammatory markers decreased, and ECMO was successfully weaned.

Conclusion

VV-ECMO is of critical value in managing septic shock and ARDS caused by severe anaerobic infections, effectively improving oxygenation and supporting organ function. This case highlights the pivotal role of airway management, VV-ECMO support, and comprehensive therapeutic strategies in the management of complex infectious ARDS, providing valuable insights for similar clinical scenarios.

Comparison of high-flow nasal oxygen therapy and noninvasive ventilation in suspected sepsis patients with acute respiratory distress in the emergency department: a retrospective cohort study

INTRODUCTION

High-flow nasal cannula (HFNC) and non-invasive ventilation (NIV) are widely utilized respiratory support modalities for patients presenting with suspected sepsis and respiratory distress.This study aims to compare the 48-hour intubation rates between HFNC and NIV therapies in patients with suspected sepsis and respiratory distress.

METHODS

This retrospective cohort study collected data over a 2-year period (January 2022 to December 2023) from patients presenting to the ED of Ramathibodi Hospital with suspected sepsis who received respiratory support with either HFNC or NIV. To analyze the incidence of intubation and 28-day mortality, we employed multivariable Cox regression to estimate hazard ratios (HRs). The hospital length of stay and ventilator-free days at 28 days were compared using Gaussian regression analysis.

RESULTS

A total of 546 patients met the inclusion criteria. The intubation at 48 h was 17.39% in the HFNC group and 19.47% in the NIV group (adjusted HR 0.74; 95% CI, 0.48 to 1.15; p = 0.18). The HFNC group demonstrated a trend toward lower 28-day mortality than the NIV group (adjusted HR 0.34; 95% CI, 0.12 to 1.02; p = 0.053). Additionally, the HFNC group had significantly more ventilator-free days (adjusted mean difference 1.46 days; 95% CI, 0.11 to 2.80; p = 0.034).

CONCLUSIONS

In patients with suspected sepsis and acute respiratory distress, HFNC therapy did not significantly reduce the 48-hour intubation compared to NIV. However, HFNC was associated with a trend toward lower 28-day mortality and a significantly greater number of ventilator-free days on day 28.

TRIAL REGISTRATION

This trial was retrospectively registered in the Thai Clinical Trial Registry on 09 November 2023. The TCTR identification number is TCTR20231109004.

Therapeutic Effects of TN13 Peptide on Acute Respiratory Distress Syndrome and Sepsis Models In Vivo

Background/Objectives: Regulation of acute inflammatory responses is crucial for host mortality and morbidity induced by pathogens. The pathogenesis of acute respiratory distress syndrome (ARDS) and sepsis are associated with systemic inflammation. p38 MAPK is a crucial regulator of inflammatory responses and is a potential target for acute inflammatory diseases, including ARDS and sepsis. We investigated the therapeutic effects of the TAT-TN13 peptide (TN13) on severe inflammatory diseases, including ARDS and sepsis, in vivo. Methods: To establish the ARDS model, C57BL/6 mice were intranasally (i.n.) administered lipopolysaccharide (LPS; 5 mg/kg, 40 µL) to induce lung inflammation. As a positive control, dexamethasone (DEX; 0.2 mg/kg) was administered intraperitoneally (i.n.) 1 h post-LPS exposure. In the experimental groups, TN13 was administered intranasally (i.n.) at doses of 2.5 mg or 5 mg/kg at the same time point. In the LPS-induced sepsis model, mice received an intraperitoneal injection of LPS (20 mg/kg) to induce systemic inflammation. TN13 (25 mg/kg, i.p.) was administered 1 h after LPS treatment. Control mice received phosphate-buffered saline (PBS). Lung histopathology, inflammatory cell infiltration, cytokine levels, and survival rates were assessed to evaluate TN13 efficacy. Results: TN13 significantly reduced inflammatory cell recruitment and cytokine production in the lungs, thereby mitigating LPS-induced ARDS. In the sepsis model, TN13 treatment improved survival rates by suppressing inflammatory responses. Mechanistically, TN13 exerted its effects by inhibiting the p38 MAPK/NF-κB signaling pathway. Conclusions: These results collectively suggested that TN13 could be an effective treatment option for severe inflammatory diseases.

HNF4A mitigates sepsis-associated lung injury by upregulating NCOR2/GR/STAB1 axis and promoting macrophage polarization towards M2 phenotype

Sepsis can trigger systemic inflammation and lead to detrimental effects on several organs, with particular emphasis on the lungs. In sepsis-associated lung injury, macrophages assume a pivotal role, as their overactivation could facilitate the secretion of inflammatory factors and the imbalance of polarization. Hepatocyte nuclear factor 4 alpha (HNF4A) has been reported its potential involvement in the regulation of inflammatory response and macrophage polarization. This study discusses the role and mechanism of HNF4A in sepsis-induced lung damage. HNF4A exhibits a decrease in expression by analyzing the differentially expressed genes in the lungs of septic mice from the Gene Expression Omnibus dataset GSE15379. Then, we established a mouse sepsis model through a cecal ligation and puncture method and observed that the expression of HNF4A was reduced in both lung tissues and alveolar macrophages. To evaluate the function of HNF4A, we overexpressed HNF4A mediated by adenovirus vectors, which were injected into mice. We found that HNF4A overexpression resulted in a higher survival rate in septic mice and an amelioration of pulmonary damage. Meanwhile, HNF4A overexpression mitigated the infiltration of inflammatory cells and impeded the M1 polarization but facilitated the M2 polarization of macrophages in the lung tissues or the alveolar lavage fluid. In vitro, we treated bone marrow-derived macrophages with interleukin-4. Consistent results were obtained that HNF4A overexpression promoted the M2 polarization of macrophages. Mechanistically, we found that HNF4A transcriptionally regulate the expression of nuclear receptor coactivator 2 (NCOA2) through binding to its promoter region. NCOA2 interacted with glucocorticoid receptor (GR). Stabilin 1 (STAB1) was selected as a possible target by transcriptome sequencing analysis. Functional experiments confirmed STAB1 as a downstream target of the HNF4A/NCOA2/GR axis. Overall, this research investigated the potential impact of HNF4A on pulmonary injury in sepsis. It is suggested that one of the regulatory mechanisms involved in this association may be the NCOR2/GR/STAB1 axis.

Inhibition of proton sensor GPR68 suppresses endothelial dysfunction and acute lung injury caused by Staphylococcus aureus bacterial particles

Lung bacterial infections, including hospital-acquired pneumonia, remain a serious problem for public health. Endothelial cell (EC) exposure to heat-killed Staphylococcus aureus (HKSA) represents a clinical scenario of high titers of killed bacterial particles present in the host after antibiotic therapy, which triggers inflammatory cascades, cytokine storms, and EC dysfunction leading to acute lung injury (ALI). GPR68 is a member of the proton-sensing G protein-coupled receptor family. Acting as a pH sensor, GPR68 becomes activated upon pH reduction and contributes to pathologic cell responses by activating ER stress and unfolded protein response. This study investigated the role of GPR68 in HKSA-induced EC dysfunction and HKSA-induced ALI. HKSA robustly increased GPR68 mRNA levels in human pulmonary EC and directly stimulated GPR68 activity. A selective GPR68 small molecule inhibitor, OGM-8345, attenuated HKSA-induced EC permeability and protected cell junction integrity. OGM-8345 inhibited HKSA-induced activation of inflammatory genes TNF-α, IL-6, IL-8, IL-1β, and CXCL5 and decreased cytokine secretion by HKSA-challenged EC. Co-treatment with the GPR68 activator Ogerin or medium acidification to pH 6.5 augmented HKSA-induced EC dysfunction, which was rescued by OGM-8345. Intratracheal HKSA injection increased vascular leak and lung inflammation in mice which were monitored by lung Evans blue extravasation, increased cell and protein count in bronchoalveolar lavage, and mRNA expression of inflammatory genes. ALI and barrier dysfunction was attenuated by OGM-8345. We show for the first time the role of GPR68 in mediating HKSA-induced lung injury and the strong potential for OGM-8345 as a therapeutic treatment of bacterial pathogen-induced ALI associated with tissue acidification.

Circular RNA-Cacna1d Plays a Critical Role in Sepsis-induced Lung Injury by Sponging microRNA-185-5p

The role of circular RNAs (circRNAs) in sepsis-induced lung injury is not clear. This study investigated the role and molecular mechanism of a novel circRNA in sepsis-induced lung injury and explored its prognostic value in patients with sepsis. In this study, aberrant circRNA expression profiling in lung tissues from mice with sepsis-induced lung injury was analyzed using high-throughput sequencing. circRNA-Cacna1d was verified by qRT-PCR, and its biological function in sepsis-induced lung injury was validated in vitro and in vivo. The interactions among circRNA-Cacna1d, microRNAs (miRNAs), and their downstream genes were verified. Furthermore, the clinical value of circRNA-Cacna1d in peripheral blood from patients with sepsis was also evaluated. We found that circRNA-Cacna1d expression was significantly increased in lung tissues of mice with sepsis and in microvascular endothelial cells after LPS challenge. circRNA-Cacna1d knockdown alleviated inflammatory response and ameliorated the permeability of vascular endothelium, thereby mitigating sepsis-induced lung injury and significantly improving the survival rate of mice with sepsis. Mechanistically, circRNA-Cacna1d directly interacted with miRNA-185-5p and functioned as a miRNA sponge to regulate the RhoA/ROCK1 signaling pathway. The expression level of circRNA-Cacna1d in patients with early sepsis was significantly higher than that in the healthy control subjects. Higher levels of circRNA-Cacna1d in patients with sepsis were associated with increased disease severity and poorer outcomes. In conclusions, circRNA-Cacna1d may play a role in sepsis-induced lung injury by regulating the RhoA/ROCK1 axis by acting as a miRNA-185-5p sponge. circRNA-Cacna1d is a potential therapeutic target for sepsis-induced lung injury and a prognostic biomarker in sepsis.

Role of mesenchymal stem cells in sepsis and their therapeutic potential in sepsis‑associated myopathy (Review)

Sepsis‑induced myopathy (SIM) is one of the leading causes of death in critically ill patients. SIM mainly involves the respiratory and skeletal muscles of patients, resulting in an increased risk of lung infection, aggravated respiratory failure, and prolonged mechanical ventilation and hospital stay. SIM is also an independent risk factor associated with increased mortality in critically ill patients. At present, no effective treatment for SIM has yet been established. However, mesenchymal stem cells (MSCs) have emerged as a promising therapeutic approach and have been utilized in the treatment of various clinical conditions. A significant body of basic and clinical research supports the efficacy of MSCs in managing sepsis and muscle‑related diseases. This literature review aims to explore the relationship between MSCs and sepsis, as well as their impact on skeletal muscle‑associated diseases. Additionally, the present review discusses the potential mechanisms and therapeutic benefits of MSCs in the context of SIM.

Aquaporins in sepsis- an update

Aquaporins (AQPs), a family of membrane proteins that facilitate the transport of water and small solutes, have garnered increasing attention for their role in sepsis, not only in fluid balance but also in immune modulation and metabolic regulation. Sepsis, characterized by an excessive and dysregulated immune response to infection, leads to widespread organ dysfunction and significant mortality. This review focuses on the emerging roles of aquaporins in immune metabolism and their potential as therapeutic targets in sepsis, with particular attention to the modulation of inflammatory responses and organ protection. Additionally, it explores the diverse roles of aquaporins across various organ systems, highlighting their contributions to renal function, pulmonary gas exchange, cardiac protection, and gastrointestinal barrier integrity in the context of sepsis. Recent studies suggest that AQPs, particularly aquaglyceroporins like AQP3, AQP7, AQP9, and AQP10, play pivotal roles in immune cell metabolism and offer new therapeutic avenues for sepsis treatment. In the context of sepsis, immune cells undergo metabolic shifts to meet the heightened energy demands of the inflammatory response. A key adaptation is the shift from oxidative phosphorylation (OXPHOS) to aerobic glycolysis, where pyruvate is converted to lactate, enabling faster ATP production. AQPs, particularly aquaglyceroporins, may facilitate this process by transporting glycerol, a substrate that fuels glycolysis. AQP3, for example, enhances glucose metabolism by transporting glycerol and complementing glucose uptake via GLUT1, while also regulating O-GlcNAcylation, a post-translational modification that boosts glycolytic flux. AQP7 could further contributes to immune cell energy production by influencing lipid metabolism and promoting glycolysis through p38 signaling. These mechanisms could be crucial for maintaining the energy supply needed for an effective immune response during sepsis. Beyond metabolism, AQPs also regulate key immune functions. AQP9, highly expressed in septic patients, is essential for neutrophil migration and activation, both of which are critical for controlling infection. AQP3, on the other hand, modulates inflammation through the Toll-like receptor 4 (TLR4) pathway, while AQP1 plays a role in immune responses by activating the PI3K pathway, promoting macrophage polarization, and protecting against lipopolysaccharide (LPS)-induced acute kidney injury (AKI). These insights into the immunoregulatory roles of AQPs suggest their potential as therapeutic targets to modulate inflammation in sepsis. Therapeutically, AQPs present promising targets for reducing organ damage and improving survival in sepsis. For instance, inhibition of AQP9 with compounds like HTS13286 or RG100204 has been shown to reduce inflammation and improve survival by modulating NF-κB signaling and decreasing oxidative stress in animal models. AQP5 inhibition with methazolamide and furosemide has demonstrated efficacy in reducing immune cell migration and lung injury, suggesting its potential in treating acute lung injury (ALI) in sepsis. Additionally, the regulation of AQP1 through non-coding RNAs (lncRNAs and miRNAs) may offer new strategies to mitigate organ damage and inflammatory responses. Moreover, AQPs have emerged as potential biomarkers for sepsis progression and outcomes. Altered expression of AQPs, such as AQP1, AQP3, and AQP5, correlates with sepsis severity, and polymorphisms in AQP5 have been linked to better survival rates and improved outcomes in sepsis-related acute respiratory distress syndrome (ARDS). This suggests that AQP expression could be used to stratify patients and tailor treatments based on individual AQP profiles. In conclusion, AQPs play a multifaceted role in the pathophysiology of sepsis, extending beyond fluid balance to crucial involvement in immune metabolism and inflammation. Targeting AQPs offers novel therapeutic strategies to mitigate sepsis-induced organ damage and improve patient survival. Continued research into the metabolic and immune functions of AQPs will be essential for developing targeted therapies that can be translated into clinical practice.

α4 Nicotinic Acetylcholine Receptors in Lipopolysaccharide-Related Lung Inflammation

Sepsis remains an important healthcare challenge. The lungs are often affected in sepsis, resulting in acute lung injury characterized by inflammation. Mechanisms involving lipopolysaccharide (LPS) stimulation of toll-like receptor (TLR) signaling with induction of proinflammatory pathways have been implicated in this process. To date, however, studies targeting these pathways have failed to improve outcomes. We have found that LPS may also promote lung injury through the activation of α4 nicotinic acetylcholine receptors (α4 nAChRs) in immune cells. We observed increased expression of α4 nAChRs in human THP-1 monocytic cells exposed to LPS (100 ng/mL, 24 h). We also observed that LPS stimulated the expression of other relevant genes, including tumor necrosis factor-α, interleukin-1β, plasminogen activator inhibitor-1, the solute carrier family 7 member 11, extracellular superoxide dismutase, and transforming growth factor-β1. Of interest, dihydro-β-erythroidine hydrobromide (DHβE), a specific chemical inhibitor of α4 nAChRs, inhibited the LPS-induced expression of these genes. We generated mice with a global knockout mutation of the α4 nAChR subunit in the C57BL/6 background using CRISPR/Cas9 technology. The lungs of these LPS-treated animals demonstrated a reduction in the expression of the above-mentioned genes when compared with the lungs of wild-type animals. In support of the role of oxidative stress, we observed that LPS induced expression of the cystine transporter Slc7a11 in both THP-1 cells and in wild-type mouse lungs. The effects of LPS on THP-1 cells were blocked by the thiol antioxidant N-acetylcysteine and mimicked by redox stress. Importantly, the induction of IL-1β by redox stress was inhibited by the α4 nAChR inhibitor DHβE. Finally, we showed that LPS stimulated calcium influx in THP-1 cells, which was blocked by the α4 nAChR inhibitor. Our observations suggest that LPS promotes lung injury by stimulating redox stress, which activates α4 nAChR signaling and drives proinflammatory cytokine expression.

The multi-herbal decoction SH003 alleviates LPS-induced acute lung injury by targeting inflammasome and extracellular traps in neutrophils

BACKGROUND

Acute lung injury (ALI) is a devastating condition caused by sepsis, pneumonia, trauma, and more recently, COVID-19. SH003, an herbal formula consisted of Astragalus membranaceus, Angelica gigas and Trichosanthes kirilowii, is known for its effects on cancer and immunoregulation.

HYPOTHESIS/PURPOSE

Previous studies show SH003 exerts a promising anti-inflammatory effect. This study investigates the effect of modified SH003 on ALI using in silico, in vivo, and in vitro models.

STUDY DESIGN AND METHODS

We performed in silico-based analysis of SH003 on ALI-related pathways. C57BL/6 mice were intraperitoneally subjected to lipopolysaccharide (LPS) to induce septic ALI, followed by oral administration of SH003 for 2 weeks. Dexamethasone was used as the positive control. Human peripheral blood-derived polymorphonuclear neutrophils (PMN) were used to investigate the effect and mechanisms of SH003 on neutrophil extracellular trap (NET) formation.

RESULTS

Network pharmacology analysis suggested SH003 regulates lung inflammation by modulating NET formation. SH003 significantly reduced mortality in sepsis in vivo by inhibiting local and systemic inflammation, likely via nuclear factor kappa B and mitogen-activated protein kinase pathways-mediated inflammasome suppression. SH003 also decreased NET-related markers in lung tissues and inhibited LPS- and phorbol myristate acetate-induced NET formation in PMN. Cytometry time-of-flight analysis confirmed regulation of NETosis-related pathways by SH003.

CONCLUSION

SH003 effectively inhibits excessive immune responses in the lung by suppressing inflammasome activation and NET formation. These findings suggest SH003 as a potential therapeutic agent for septic ALI.

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.

Impact of the timing of invasive mechanical ventilation in patients with sepsis: a multicenter cohort study

BACKGROUND

The potential adverse effects associated with invasive mechanical ventilation (MV) can lead to delayed decisions on starting MV. We aimed to explore the association between the timing of MV and the clinical outcomes in patients with sepsis ventilated in intensive care unit (ICU).

METHODS

We analyzed data of adult patients with sepsis between September 2019 and December 2021. Data was collected through the Korean Sepsis Alliance from 20 hospitals in Korea. Patients who were admitted to ICU and received MV were included in the study. Patients were divided into 'early MV' and 'delayed MV' groups based on whether they were on MV on the first day of ICU admission or later. Propensity score matching was applied, and patients in the two groups were compared on a 1:1 ratio to overcome bias between the groups. Outcomes including ICU mortality, hospital mortality, length of hospital and ICU stay, and organ failure at ICU discharge were compared.

RESULTS

Out of 2440 patients on MV during ICU stay, 2119 'early MV' and 321 'delayed MV' cases were analyzed. The propensity score matching identified 295 patients in each group with similar baseline characteristics. ICU mortality was lower in 'early MV' group than 'delayed MV' group (36.3% vs. 46.4%; odds ratio, 0.66; 95% confidence interval, 0.47-0.93; p = 0.015). 'Early MV' group had lower in-hospital mortality, shorter ICU stay, and required tracheostomy less frequently than 'delayed MV' group. Multivariable logistic regression model identified 'early MV' as associated with lower ICU mortality (odds ratio, 0.38; 95% confidence interval, 0.29-0.50; p < 0.001).

CONCLUSION

In patients with sepsis ventilated in ICU, earlier start (first day of ICU admission) of MV may be associated with lower mortality.

COVID-19 Related Acute Respiratory Distress Syndrome versus Classical Acute Respiratory Distress Syndrome Patients: Inflammatory Biomarkers as Predictors of Mortality in Pulmonary Septic Shock

Introduction and Objectives

Coronavirus disease-2019 (COVID-19)-related severe acute respiratory distress syndrome (ARDS) differs pathophysiological from other pulmonary septic shock-related ARDS. Thus, we assessed whether all-cause in-hospital mortality differs for severe COVID-19-related and classical severe ARDS and which inflammatory biomarkers can predict mortality among these patients.

Material and Methods

This single-center, retrospective, observational cohort study included pulmonary septic shock patients (n = 114) with COVID-19-related and classical severe ARDS admitted in the Intensive Care Unit.

Results

Patients with a mean age of 73 (IQR 62-82), predominantly male (63%), were divided into two groups based on outcomes: survivors (n = 50) and non-survivors (n = 64). COVID-19-related severe ARDS (n = 48) accounts for 75% of deaths. Present comorbidities like heart disease (p = 0.043), neurologic disorders (p = 0.018), and liver disease (p = 0.038) were associated with in-hospital mortality, as well. Regarding inflammatory biomarkers, the AUC/c-statistic was 0.656 (95% CI: 0.53-0.759) for leukocytes, 0.613 (95% CI: 0.509-0.717) C-reactive protein (CRP) and 0.651 (95% CI: 0.548-0.753) for procalcitonin in predicting all-cause in-hospital mortality among patients with pulmonary septic shock and severe ARDS.

Conclusion

Patients with pulmonary septic shock and with COVID-19-related severe ARDS had a higher incidence of in-hospital mortality than those with classical severe ARDS. The high value of leukocytes, C-reactive protein, and procalcitonin were predictive for all-cause in-hospital mortality in patients with pulmonary septic shock and ARDS. Infection with COVID-19 was an independent predictor of in-hospital mortality in the presence of ARDS.

Hydroxychloroquine attenuates sepsis-induced acute respiratory distress syndrome in rats

BACKGROUND

This study investigates the effects of hydroxychloroquine (HCQ) on a sepsis-induced acute respiratory distress syndrome (ARDS) model in rats, initiated by a fecal intraperitoneal injection procedure (FIP).

METHODS

Three groups were established: control (n=8), FIP + saline (n=7), and FIP + HCQ (20 mg/kg/day) (n=9). Blood samples were collected for arterial blood gas and biochemical analyses, and bilateral pneumonectomy was performed for histopathologic examination.

RESULTS

In the FIP + saline group, PaO2 decreased and PaCO2 increased, whereas these levels normalized in the FIP + HCQ group compared to the control (p<0.001 and p<0.05, respectively). Histopathological scores for alveolar congestion, perivascular/interstitial edema, hemorrhage in alveolar tissue, leukocyte infiltration or aggregation in air spaces/vascular walls, and alveolar wall/hyaline membrane thickness increased in the FIP + saline group compared to the control group (p<0.01). These scores decreased in the FIP + HCQ group compared to the FIP + saline group (p<0.01). HCQ reversed the sepsis-induced increase in malondialdehyde, tumor necrosis factor-alpha, interleukin-6, and lactic acid.

CONCLUSION

HCQ may be an effective and safe option to mitigate the severe progression of ARDS.

Mortality and its associated factors among mechanically ventilated adult patients in the intensive care units of referral hospitals in Northwest Amhara, Ethiopia, 2023

Background

Worldwide, nearly half of the patients admitted to intensive care units require ventilatory support. Despite advances in intensive care unit patient management and mechanical ventilator utilization, the odds of mortality among mechanically ventilated patients are higher in resource-limited settings. Little is known about the mortality of patients on mechanical ventilation outside the capital of Ethiopia. This study aimed to assess mortality and its associated factors among mechanically ventilated adult patients in intensive care units.

Method

An institutional-based cross-sectional study was conducted on mechanically ventilated patients in intensive care units from 1 February 2020 to 1 March 2023. A simple random sampling technique was used to select 434 patients' charts. A data extraction tool designed on the Kobo toolbox, a smartphone data collection platform, was used to collect the data. The data were exported into Microsoft Excel 2019 and then into Stata 17 for data management and analysis. Descriptive statistics were used to summarize the characteristics of the study participants. A bivariable logistic regression was conducted, and variables with p ≤ 0.20 were recruited for multivariable analysis. Statistical significance was declared at p < 0.05, and the strength of associations was summarized using an adjusted odds ratio with 95% confidence intervals.

Result

A total of 404 charts of mechanically ventilated patients were included, with a completeness rate of 93.1%. The overall proportion of mortality was 62.87%, with a 95% CI of (58.16-67.58). In the multivariable logistic regression, age 41-70 years (AOR: 4.28, 95% CI: 1.89-9.62), sepsis (AOR: 2.43, 95% CI: 1.08-5.46), reintubation (AOR: 2.76, 95% CI: 1.06-7.21), and sedation use (AOR: 0.41, 95% CI: 0.18-0.98) were found to be significant factors associated with the mortality of mechanically ventilated patients in the intensive care unit.

Conclusion

The magnitude of mortality among mechanically ventilated patients was high. Factors associated with increased odds of death were advanced age, sepsis, and reintubation. However, sedation use was a factor associated with decreased mortality. Healthcare professionals in intensive care units should pay special attention to patients with sepsis, those requiring reintubation, those undergoing sedation, and those who are of advanced age.

Bakuchiol regulates TLR4/MyD88/NF-κB and Keap1/Nrf2/HO-1 pathways to protect against LPS-induced acute lung injury in vitro and in vivo

Bakuchiol (Bak) possesses a protective effect in acute lung injury (ALI). Nonetheless, the molecular processes that regulate the protective activity of Bak in ALI remain elusive. Lipopolysaccharide (LPS)-treated rats and RLE-6TN cells were used as the ALI models in vivo and in vitro to investigate the function and mechanism of Bak. Rats were divided into four groups: control, LPS, LPS + Bak (30 mg/kg), and LPS + Bak (60 mg/kg). RLE-6TN cells were assigned into four groups: control, LPS, LPS + Bak (10 µM), and LPS + Bak (20 µM). Myeloperoxidase (MPO) and 4-hydroxy-2-nonenal (4-HNE) levels were detected by immunohistochemistry (IHC). The levels of TNF-α, IL-6, and IL-1β were quantified by ELISA. Apoptosis was analyzed by TdT-mediated dUTP nick-end labeling (TUNEL) staining and flow cytometry. Malondialdehyde (MDA), superoxide dismutase (SOD), glutathione peroxidase (GSH-Px), and reactive oxygen species (ROS) were assayed to evaluate oxidative stress. In LPS-induced rats, Bak attenuated pathological injury, lung wet/dry weight ratio, MPO expression, and protein concentration and cell number in bronchial alveolar lavage fluid (BALF). Bak decreased the secretion of TNF-α, IL-6, and IL-1β in BALF. Bak reduced MDA content and 4-HNE expression, and increased SOD and GSH-Px activities in lung tissues. Bak also repressed pulmonary apoptosis by decreasing Bax expression and enhancing Bcl-2 expression. In LPS-treated RLE-6TN cells, Bak downregulated the mRNA levels of TNF-α, IL-6, and IL-1β and inhibited the protein expression of iNOS and COX2. Bak decreased MDA level and ROS production and increased SOD and GSH-Px activities. Bak also suppressed cell apoptosis, reduced Bax expression, and increased Bcl-2 expression. Moreover, Bak decreased the expression of TLR4, MyD88, p-IκBα, and p-p65. Additionally, Bak inhibited Keap1 expression and increased Nrf2 and HO-1 levels. Bak protects against LPS-induced inflammation, oxidative stress, and apoptosis in ALI by regulating TLR4/MyD88/NF-κB and Keap1/Nrf2/HO-1 pathways.

Exploring the ferroptosis-related gene lipocalin 2 as a potential biomarker for sepsis-induced acute respiratory distress syndrome based on machine learning

BACKGROUND

Sepsis is a major cause of mortality in patients, and ARDS is one of the most common outcomes. The pathophysiology of acute respiratory distress syndrome (ARDS) caused by sepsis is significantly impacted by genes related to ferroptosis.

METHODS

In this study, Weighted gene co-expression network analysis (WGCNA), protein-protein interaction (PPI) networks, functional enrichment analysis, and machine learning were employed to identify characterized genes and to construct receiver operating characteristic (ROC) curves. Additionally, DNA methylation levels were quantified and single-cell analysis was conducted. To validate the alterations in the expression of Lipocalin-2 (LCN2) and ferroptosis-related proteins in the in vitro model, Western blotting was carried out, and the changes in intracellular ROS and Fe2+ levels were detected.

RESULTS

A combination of eight machine learning algorithms, including RFE, LASSO, RandomForest, SVM-RFE, GBDT, Bagging, XGBoost, and Boruta, were used with a machine learning model to highlight the significance of LCN2 as a key gene in sepsis-induced ARDS. Analysis of immune cell infiltration showed a positive correlation between neutrophils and LCN2. In a cell model induced by LPS, it was found that Ferrostatin-1 (Fer-1), a ferroptosis inhibitor, was able to reverse the expression of LCN2. Knocking down LCN2 in BEAS-2B cells reversed the LPS-induced lipid peroxidation, Fe2+ levels, ACSL4, and GPX4 levels, indicating that LCN2, a ferroptosis-related gene (FRG), plays a crucial role in mediating ferroptosis.

CONCLUSION

Upon establishing an FRG model for individuals with sepsis-induced ARDS, we determined that LCN2 could be a dependable marker for predicting survival in these patients. This finding provides a basis for more accurate ARDS diagnosis and the exploration of innovative treatment options.

Identification and Analysis of PANoptosis-Related Genes in Sepsis-Induced Lung Injury by Bioinformatics and Experimental Verification

Purpose

Sepsis-induced lung injury (SLI) is a serious complication of sepsis. PANoptosis, a novel form of inflammatory programmed cell death that is not yet to be fully investigated in SLI. Our research aims to screen and validate the signature genes of PANoptosis in SLI by bioinformatics and in vivo experiment.

Methods

SLI-related datasets were downloaded from NCBI Gene Expression Omnibus (GEO) database. Differentially expressed genes (DEGs) of SLI were identified and intersected with the PANoptosis gene set to obtain DEGs related to PANoptosis (SPAN_DEGs). Then, Protein-Protein Interaction (PPI) network and functional enrichment analysis were conducted based on SPAN_DEGs. SVM-REF, LASSO and RandomForest three algorithms were combined to identify the signature genes. The Nomogram and ROC curves were performed to predict diagnostic value. Immune infiltration analysis, correlation analysis and differential expression analysis were used to explore the immunological characterization, correlation and expression levels of the signature genes. Finally, H&E staining and qRT-PCR were conducted for further verification in vivo experiment.

Results

Twenty-four SPAN_DEGs were identified by intersecting 675 DEGs with the 277 PANoptosis genes. Four signature genes (CD14, GSDMD, IL1β, and FAS) were identified by three machine learning algorithms, which were highly expressed in the SLI group, and had high diagnostic value in the diagnostic model. Moreover, immune infiltration analysis showed that most immune cells and immune-related functions were higher in the SLI group than those in the control group and were closely associated with the signature genes. Finally, it was confirmed that the cecum ligation and puncture (CLP) group mice showed significant pathological damage in lung tissues, and the mRNA expression levels of CD14, IL1β, and FAS were significantly higher than the sham group.

Conclusion

CD14, FAS, and IL1β may be the signature genes in PANoptosis to drive the progression of SLI and involved in regulating immune processes.

Unraveling the role of HIF-1α in sepsis: from pathophysiology to potential therapeutics-a narrative review

Sepsis is characterized by organ dysfunction resulting from a dysregulated inflammatory response triggered by infection, involving multifactorial and intricate molecular mechanisms. Hypoxia-inducible factor-1α (HIF-1α), a notable transcription factor, assumes a pivotal role in the onset and progression of sepsis. This review aims to furnish a comprehensive overview of HIF-1α's mechanism of action in sepsis, scrutinizing its involvement in inflammatory regulation, hypoxia adaptation, immune response, and organ dysfunction. The review encompasses an analysis of the structural features, regulatory activation, and downstream signaling pathways of HIF-1α, alongside its mechanism of action in the pathophysiological processes of sepsis. Furthermore, it will delve into the roles of HIF-1α in modulating the inflammatory response, including its association with inflammatory mediators, immune cell activation, and vasodilation. Additionally, attention will be directed toward the regulatory function of HIF-1α in hypoxic environments and its linkage with intracellular signaling, oxidative stress, and mitochondrial damage. Finally, the potential therapeutic value of HIF-1α as a targeted therapy and its significance in the clinical management of sepsis will be discussed, aiming to serve as a significant reference for an in-depth understanding of sepsis pathogenesis and potential therapeutic targets, as well as to establish a theoretical foundation for clinical applications.

Advances of presepsin in sepsis-associated ARDS

This article reviews the correlation between presepsin and sepsis and the resulting acute respiratory distress syndrome (ARDS). ARDS is a severe complication of sepsis. Despite the successful application of protective mechanical ventilation, restrictive fluid therapy, and neuromuscular blockade, which have effectively reduced the morbidity and mortality associated with ARDS, the mortality rate among patients with sepsis-associated ARDS remains notably high. The challenge lies in the prediction of ARDS onset and the timely implementation of intervention strategies. Recent studies have demonstrated significant variations in presepsin (PSEP) levels between patients with sepsis and those without, particularly in the context of ARDS. Moreover, these studies have revealed substantially elevated PSEP levels in patients with sepsis-associated ARDS compared to those with nonsepsis-associated ARDS. Consequently, PSEP emerges as a valuable biomarker for identifying patients with an increased risk of sepsis-associated ARDS and to predict in-hospital mortality.

Crosstalk-free graphene-liquid elastomer based printed sensors for unobtrusive respiratory monitoring

Flexible strain sensors have garnered attraction in the human healthcare domain. However, caveats like crosstalk and noise associated with the output signal of such a sensor often limit the accuracy. Hence, developing a strain sensor via frugal engineering is critical, thereby warranting its mass utility. A stencil printable graphene/liquid elastomeric crosstalk-free strain sensor for unobtrusive respiratory monitoring is reported herein. Printing supports the frugality of the process and avoids complex fabrication. The sensor was mounted on a wearable mask, and the sensor console was fabricated. The console demonstrated the capability to detect the respiratory profile at room and low temperature (-26 °C) with an SNR of -12.85 dB. Developed sensors could nullify the impact of temperature and humidity and generate respiratory signals due to strain induced by breathing. A model experiment was conducted to support the fidelity of the strain mechanism. The console demonstrated excellent stability (over 500 cycles) with a sensitivity of -196.56 (0-0.17% strain) and 117.49 (0.17-0.34% strain). The console could accurately determine conditions like eupnea, tachypnoea, etc., and transmit the data wirelessly via Bluetooth. These findings solve major caveats in flexible sensor development by focusing on selectivity, sensitivity, and stability.

The Therapeutic Potential of (+)-Afzelechin for Alleviating Sepsis-Associated Pulmonary Injury

Sepsis-induced acute lung injury (ALI) poses a common and formidable challenge in clinical practice, currently lacking efficacious therapeutic approaches. This study delves into the evaluation of (+)-afzelechin (AZC), a natural compound derived from Bergenia ligulata with a diverse array of properties, encompassing antioxidant, anticancer, antimicrobial, and cardiovascular effects to ascertain its effectiveness and underlying mechanisms in mitigating sepsis-induced ALI through animal experimentation. An ALI mouse model induced by sepsis was established through lipopolysaccharide (LPS) administration, and various analytical techniques, including quantitative real-time polymerase chain reaction, Western blotting, and enzyme-linked immunosorbent assay were employed to gauge inflammatory cytokine levels, lung injury, and associated signaling pathways. The animal experiments revealed that AZC offered safeguards against lung injury induced by LPS while reducing inflammatory cytokine levels in both blood serum and lung tissue. Western blotting experiments revealed AZC's downregulation of the toll-like receptor (TLR)4/NF-κB pathway and the upregulation of PI3K/Akt, coupled with inhibition of the Hippo and Rho signaling pathways. These findings underscore AZC's efficacy in ameliorating sepsis-induced ALI by modulating cytokine storms and curtailing inflammation via the regulation of TLR4/NF-κB, PI3K/Akt, Hippo, and Rho signaling pathways. This work serves as a foundation for additional exploration into AZC's mechanisms and its potential as a therapy for sepsis-induced ALI. Animals in accordance with Kyungpook National University (IRB No. KNU 2022-174).

A gene network database for the identification of key genes for diagnosis, prognosis, and treatment in sepsis

Sepsis and sepsis-related diseases cause a high rate of mortality worldwide. The molecular and cellular mechanisms of sepsis are still unclear. We aim to identify key genes in sepsis and reveal potential disease mechanisms. Six sepsis-related blood transcriptome datasets were collected and analyzed by weighted gene co-expression network analysis (WGCNA). Functional annotation was performed in the gProfiler tool. DSigDB was used for drug signature enrichment analysis. The proportion of immune cells was estimated by the CIBERSORT tool. The relationships between modules, immune cells, and survival were identified by correlation analysis and survival analysis. A total of 37 stable co-expressed gene modules were identified. These modules were associated with the critical biology process in sepsis. Four modules can independently separate patients with long and short survival. Three modules can recurrently separate sepsis and normal patients with high accuracy. Some modules can separate bacterial pneumonia, influenza pneumonia, mixed bacterial and influenza A pneumonia, and non-infective systemic inflammatory response syndrome (SIRS). Drug signature analysis identified drugs associated with sepsis, such as testosterone, phytoestrogens, ibuprofen, urea, dichlorvos, potassium persulfate, and vitamin B12. Finally, a gene co-expression network database was constructed ( https://liqs.shinyapps.io/sepsis/ ). The recurrent modules in sepsis may facilitate disease diagnosis, prognosis, and treatment.

The Role of Oral Ascorbic Acid Administration in Combination With IV N-acetylcysteine in Delaying Inflammatory Cascade in Sepsis: A Case Report

Sepsis is a life-threatening emergency that arises owing to a dysregulated host response to infection, leading to existence organ dysfunction. Vitamin C administration has led to a lower mortality rate in sepsis. N-acetylcysteine (NAC) treatment during sepsis improves hepatic function and enhances tissue oxygenation. The objective of this case report is to investigate the synergistic effect of the combination of vitamin C, thiamine, and NAC in delaying sepsis cascade and prolongation of survival time. In this case report, an oral dose of vitamin C 500 mg three times daily in combination with IV thiamine 100 mg three times daily, IV NAC, and hydrocortisone stress dose resulted in 12 days of survival of an immunocompromised patient with ventilator-associated pneumonia on single anti-pseudomonas beta-lactam antibiotic. The patient was a 60-year-old Malay female with previous bone marrow transplantation surgery and a medical history of ischemic stroke on phenytoin and valproate therapy. The patient was transferred to a medical ward in Penang General Hospital, Malaysia, due to community-acquired pneumonia. She was on ceftriaxone for five days, then sedated and ventilated in the ICU, with a shift to cefepime for three days, which was then changed to meropenem for nine days until the last day of life. Total anti-pseudomonas coverage was 12 days. The patient had multiple comorbidities from phenytoin-induced hepatic encephalopathy, acute kidney injury, and three sessions of hemodialysis. IV vitamin C was not available, so an oral dose was administered with potential efficacy in delaying the sepsis inflammatory cascade, leading to the use of a single (not double) anti-pseudomonas antibiotic for 12 days. Prolonged survival duration may be expected in the case of normal bone marrow patients with ventilator-associated pneumonia sepsis. In conclusion, Vitamin C, thiamine, and NAC combination resulted in delayed sepsis progression for 12 days and the survival of the immunocompromised patient on a single anti-pseudomonas beta-lactam antibiotic.

A 'one stone, two birds' approach with mesenchymal stem cells for acute respiratory distress syndrome and Type II diabetes mellitus

This review explores the intricate relationship between acute respiratory distress syndrome (ARDS) and Type II diabetes mellitus (T2DM). It covers ARDS epidemiology, etiology and pathophysiology, along with current treatment trends and challenges. The lipopolysaccharides (LPS) role in ARDS and its association between non-communicable diseases and COVID-19 are discussed. The review highlights the therapeutic potential of human umbilical cord-derived mesenchymal stem cells (hUC-MSCs) for ARDS and T2DM, emphasizing their immunomodulatory effects. This review also underlines how T2DM exacerbates ARDS pathophysiology and discusses the potential of hUC-MSCs in modulating immune responses. In conclusion, the review highlights the multidisciplinary approach to managing ARDS and T2DM, focusing on inflammation, oxidative stress and potential therapy of hUC-MSCs in the future.

Acute respiratory distress syndrome heterogeneity and the septic ARDS subgroup

Acute respiratory distress syndrome (ARDS) is an acute diffuse inflammatory lung injury characterized by the damage of alveolar epithelial cells and pulmonary capillary endothelial cells. It is mainly manifested by non-cardiogenic pulmonary edema, resulting from intrapulmonary and extrapulmonary risk factors. ARDS is often accompanied by immune system disturbance, both locally in the lungs and systemically. As a common heterogeneous disease in critical care medicine, researchers are often faced with the failure of clinical trials. Latent class analysis had been used to compensate for poor outcomes and found that targeted treatment after subgrouping contribute to ARDS therapy. The subphenotype of ARDS caused by sepsis has garnered attention due to its refractory nature and detrimental consequences. Sepsis stands as the most predominant extrapulmonary cause of ARDS, accounting for approximately 32% of ARDS cases. Studies indicate that sepsis-induced ARDS tends to be more severe than ARDS caused by other factors, leading to poorer prognosis and higher mortality rate. This comprehensive review delves into the immunological mechanisms of sepsis-ARDS, the heterogeneity of ARDS and existing research on targeted treatments, aiming to providing mechanism understanding and exploring ideas for accurate treatment of ARDS or sepsis-ARDS.

Exogenous IL-10 posttreatment along with TLR4 and TNFR1 blockade improves tissue antioxidant status by modulating sepsis-induced macrophage polarization

Multi-organ dysfunction is one of the major reasons behind the high mortality of sepsis throughout the world. With the pathophysiology of sepsis remaining largely unknown, the uncontrolled reactive oxygen species (ROS) production along with the decreased antioxidants contributes to the progression toward septic shock. Being the effector cells of the innate immunity system, macrophages secrete both pro-inflammatory and anti-inflammatory mediators during inflammation. Lipopolysaccharide (LPS) binding to toll-like receptor 4 (TLR4) releases TNF-α, which initiates pro-inflammatory events through tumor necrosis factor receptor 1 (TNFR1) signaling. However, it is counteracted by the anti-inflammatory interleukin 10 (IL-10) causing decreased oxidative stress. Our study thus aimed to assess the effects of exogenous IL-10 treatment post-neutralization of TLR4 and TNFR1 (by anti-TLR4 antibody and anti-TNFR1 antibody, respectively) in an in vivo murine model of LPS-sepsis. We have also examined the tissue-specific antioxidant status in the spleen, liver, and lungs along with the serum cytokine levels in adult male Swiss albino mice to determine the functional association with the disease. The results showed that administration of recombinant IL-10 post-neutralization of the receptors was beneficial in shifting the macrophage polarization to the anti-inflammatory M2 phenotype. IL-10 treatment significantly downregulated the free radicals production resulting in diminished lipid peroxidase (LPO) levels. The increased antioxidant activities of superoxide dismutase (SOD), catalase (CAT), and glutathione reductase (GRX ) conferred protection against LPS-induced sepsis. Western blot data further confirmed diminished expressions of TLR4 and TNFR1 along with suppressed stress-activated protein kinases/Jun amino-terminal kinases (SAPK/JNK) and increased SOD and CAT expressions, which altogether indicated that neutralization of TLR4 and TNFR1 along with IL-10 posttreatment might be a potential therapeutic measure for the treatment of sepsis.

Monotropein alleviates sepsis-elicited acute lung injury via the NF-κB pathway

OBJECTIVES

To address the effect and mechanism of Monotropein (Mon) on sepsis-induced acute lung injury (ALI).

METHODS

ALI model was established by lipopolysaccharide (LPS)-stimulated mouse lung epithelial cell lines (MLE-12) and cecal ligation and puncture (CLP)-treated mice, respectively. The function of Mon was examined by cell counting kit-8 (CCK-8), pathological staining, the pulmonary function examination, flow cytometry, enzyme-linked immunosorbent assay, terminal deoxynucleotidyl transferase deoxyuridine triphosphate nick end labellingand western blot.

RESULTS

Mon increased the LPS-reduced viability but decreased the LPS-evoked apoptosis rate in MLE-12 cells. Mon suppressed the concentrations and protein expressions of proinflammatory factors, and the expressions of fibrosis-related proteins in LPS-challenged MLE-12 cells compared with LPS treatment alone. Mechanically, Mon downregulated the levels of NF-κB pathway, which was confirmed with the application of the receptor activator of nuclear factor-κB ligand (RANKL). Correspondingly, RANKL reversed the ameliorative effect of Mon on the proliferation, apoptosis, inflammation and fibrosis. Moreover, Mon improved the pathological manifestations, apoptosis, the W/D ratio and pulmonary function indicators in CLP-treated mice. Consistently, Mon attenuated inflammation, fibrosis and NF-κB pathway in CLP-treated mice.

CONCLUSION

Mon inhibited apoptosis, inflammation and fibrosis to alleviate sepsis-evoked ALI via the NF-κB pathway.

Liraglutide pretreatment attenuates sepsis-induced acute lung injury

There are no effective targeted therapies to treat acute respiratory distress syndrome (ARDS). Recently, the commonly used diabetes and obesity medications, glucagon-like peptide-1 (GLP-1) receptor agonists, have been found to have anti-inflammatory properties. We, therefore, hypothesized that liraglutide pretreatment would attenuate murine sepsis-induced acute lung injury (ALI). We used a two-hit model of ALI (sepsis+hyperoxia). Sepsis was induced by intraperitoneal injection of cecal slurry (CS; 2.4 mg/g) or 5% dextrose (control) followed by hyperoxia [HO; fraction of inspired oxygen ([Formula: see text]) = 0.95] or room air (control; [Formula: see text] = 0.21). Mice were pretreated twice daily with subcutaneous injections of liraglutide (0.1 mg/kg) or saline for 3 days before initiation of CS+HO. At 24-h post CS+HO, physiological dysfunction was measured by weight loss, severity of illness score, and survival. Animals were euthanized, and bronchoalveolar lavage (BAL) fluid, lung, and spleen tissues were collected. Bacterial burden was assessed in the lung and spleen. Lung inflammation was assessed by BAL inflammatory cell numbers, cytokine concentrations, lung tissue myeloperoxidase activity, and cytokine expression. Disruption of the alveolar-capillary barrier was measured by lung wet-to-dry weight ratios, BAL protein, and epithelial injury markers (receptor for advanced glycation end products and sulfated glycosaminoglycans). Histological evidence of lung injury was quantified using a five-point score with four parameters: inflammation, edema, septal thickening, and red blood cells (RBCs) in the alveolar space. Compared with saline treatment, liraglutide improved sepsis-induced physiological dysfunction and reduced lung inflammation, alveolar-capillary barrier disruption, and lung injury. GLP-1 receptor activation may hold promise as a novel treatment strategy for sepsis-induced ARDS. Additional studies are needed to better elucidate its mechanism of action.NEW & NOTEWORTHY In this study, pretreatment with liraglutide, a commonly used diabetes medication and glucagon-like peptide-1 (GLP-1) receptor agonist, attenuated sepsis-induced acute lung injury in a two-hit mouse model (sepsis + hyperoxia). Septic mice who received the drug were less sick, lived longer, and displayed reduced lung inflammation, edema, and injury. These therapeutic effects were not dependent on weight loss. GLP-1 receptor activation may hold promise as a new treatment strategy for sepsis-induced acute respiratory distress syndrome.

The role of low-carbohydrate diets in the intensive care unit

Low-carbohydrate, high-fat (LCHF) nutrition therapy is characterized by carbohydrates comprising <26% of the daily caloric intake and a higher proportion of fat. LCHF therapies reduce exogenous glucose load, improve glycemic control, decrease inflammation, and improve clinical outcomes such as respiratory function. Given the altered metabolism in critically ill patients, LCHF nutrition therapy may be especially beneficial as it enables the conservation of protein and glucose for metabolic roles beyond energy use. In critical illness, LCHF diets have the potential to reduce hyperglycemia, improve ventilation, decrease hospital length of stay and reduce hospital costs. The purpose of this commentary piece is to describe LCHF nutrition therapy, summarize its impact on health outcomes, and discuss its role in the intensive care unit (ICU). Additional research on the effects of LCHF nutrition therapy on critically ill patients is warranted, including a focus on COVID-19.

Activation of thousands of genes in the lungs and kidneys by sepsis is countered by the selective nuclear blockade

The steady rise of sepsis globally has reached almost 49 million cases in 2017, and 11 million sepsis-related deaths. The genomic response to sepsis comprising multi-system stage of raging microbial inflammation has been reported in the whole blood, while effective treatment is lacking besides anti-microbial therapy and supportive measures. Here we show that, astoundingly, 6,237 significantly expressed genes in sepsis are increased or decreased in the lungs, the site of acute respiratory distress syndrome (ARDS). Moreover, 5,483 significantly expressed genes in sepsis are increased or decreased in the kidneys, the site of acute injury (AKI). This massive genomic response to polymicrobial sepsis is countered by the selective nuclear blockade with the cell-penetrating Nuclear Transport Checkpoint Inhibitor (NTCI). It controlled 3,735 sepsis-induced genes in the lungs and 1,951 sepsis-induced genes in the kidneys. The NTCI also reduced without antimicrobial therapy the bacterial dissemination: 18-fold in the blood, 11-fold in the lungs, and 9-fold in the spleen. This enhancement of bacterial clearance was not significant in the kidneys. Cumulatively, identification of the sepsis-responsive host's genes and their control by the selective nuclear blockade advances a better understanding of the multi-system mechanism of sepsis. Moreover, it spurs much-needed new diagnostic, therapeutic, and preventive approaches.

Investigating the link between miR-34a-5p and TLR6 signaling in sepsis-induced ARDS

Acute lung injury (ALI)/acute respiratory distress syndrome (ARDS) are lung complications diagnosed by impaired gaseous exchanges leading to mortality. From the diverse etiologies, sepsis is a prominent contributor to ALI/ARDS. In the present study, we retrieved sepsis-induced ARDS mRNA expression profile and identified 883 differentially expressed genes (DEGs). Next, we established an ARDS-specific weighted gene co-expression network (WGCN) and picked the blue module as our hub module based on highly correlated network properties. Later we subjected all hub module DEGs to form an ARDS-specific 3-node feed-forward loop (FFL) whose highest-order subnetwork motif revealed one TF (STAT6), one miRNA (miR-34a-5p), and one mRNA (TLR6). Thereafter, we screened a natural product library and identified three lead molecules that showed promising binding affinity against TLR6. We then performed molecular dynamics simulations to evaluate the stability and binding free energy of the TLR6-lead molecule complexes. Our results suggest these lead molecules may be potential therapeutic candidates for treating sepsis-induced ALI/ARDS. In-silico studies on clinical datasets for sepsis-induced ARDS indicate a possible positive interaction between miR-34a and TLR6 and an antagonizing effect on STAT6 to promote inflammation. Also, the translational study on septic mice lungs by IHC staining reveals a hike in the expression of TLR6. We report here that miR-34a actively augments the effect of sepsis on lung epithelial cell apoptosis. This study suggests that miR-34a promotes TLR6 to heighten inflammation in sepsis-induced ALI/ARDS.

Supplementary Information

The online version contains supplementary material available at 10.1007/s13205-023-03700-1.

Small Extracellular Vesicles Secreted by iPSC-Derived MSCs Ameliorate Pulmonary Inflammation and Lung Injury Induced by Sepsis through Delivery of miR-125b-5p

Background

Sepsis-induced acute lung injury is a common critical illness in intensive care units with no effective treatment is currently available. Small extracellular vesicles, secreted by mesenchymal stem cells (MSCs), derived from human-induced pluripotent stem cells (iMSC-sEV), possess striking advantages when incorporated MSCs and iPSCs, which are considered extremely promising cell-free therapeutic agents. However, no studies have yet been conducted to systemically examine the effects and underlying mechanisms of iMSC-sEV application on attenuated lung injury under sepsis conditions.

Method

iMSC-sEV were intraperitoneally administered in a rat septic lung injury model induced by cecal ligation and puncture (CLP). The efficacy of iMSC-sEV was assessed by histology, immunohistochemistry, and pro-inflammatory cytokines of bronchoalveolar lavage fluid. We also evaluated the in vitro effects of iMSC-sEV on the activation of the inflammatory response in alveolar macrophages (AMs). Small RNA sequencing was utilized to detect changes in the miRNA expression profile in lipopolysaccharide (LPS)-treated AMs after iMSC-sEV administration. The effects of miR-125b-5p on the function of AMs were studied.

Results

iMSC-sEV were able to attenuate pulmonary inflammation and lung injury following CLP-induced lung injury. iMSC-sEV were internalized by AMs and alleviated the release of inflammatory factors by inactivating the NF-κB signaling pathway. Moreover, miR-125b-5p showed a fold-change in LPS-treated AMs after iMSC-sEV administration and was enriched in iMSC-sEV. Mechanistically, iMSC-sEV transmitted miR-125b-5p into LPS-treated AMs to target TRAF6.

Conclusion

Our findings demonstrated that iMSC-sEV treatment protects against septic lung injury and exerts anti-inflammatory effects on AMs at least partially through miR-125b-5p, suggesting that iMSC-sEV may provide a novel cell-free strategy for the treatment of septic lung injury.

Association between Changes in Plasma Metabolism and Clinical Outcomes of Sepsis

Current prognostic biomarkers for sepsis have limited sensitivity and specificity. This study aimed to investigate dynamic lipid metabolomics and their association with septic immune response and clinical outcomes of sepsis. This prospective cohort study included patients with sepsis who met the Sepsis 3.0 criteria. On hospitalization days 1 (D1) and 7 (D7), plasma samples were collected, and patients underwent liquid chromatography with tandem mass spectrometry. A total of 40 patients were enrolled in the study, 24 (60%) of whom were men. The median age of the enrolled patients was 81 (68-84) years. Thirty-one (77.5%) patients had a primary infection site of the lung. Participants were allocated to the survivor (25 cases) and nonsurvivor (15 cases) groups based on their 28-day survival status. Ultimately, a total of 113 lipids were detected in plasma samples on D 1 and D 7, of which 42 lipids were most abundant in plasma samples. The nonsurvival group had significantly lower lipid expression levels in lysophosphatidylcholine (LysoPC) (16 : 0, 17 : 0,18 : 0) and 18 : 1 SM than those in the survival group (p <  0.05) on D7-D1. The correlation analysis showed that D7-D1 16 : 0 LysoPC (r = 0.367, p = 0.036),17 : 0 LysoPC (r = 0.389, p = 0.025) and 18 : 0 LysoPC(r = 0.472, p = 0.006) levels were positively correlated with the percentage of CD3+ T cell in the D7-D1. Plasma LysoPC and SM changes may serve as prognostic biomarkers for sepsis, and lipid metabolism may play a role in septic immune disturbances.

Single-cell analysis reveals dysregulated inflammatory response in peripheral blood immunity in patients with acute respiratory distress syndrome

Introduction: Acute respiratory distress syndrome (ARDS) remains a major clinical challenge for patients in intensive care units. Determining the differential mechanisms underlying ARDS with different etiologies is a key goal to improve the effectiveness of ARDS therapy. Despite growing evidence that different immune cell types are involved in ARDS, the role of altered immune cell subpopulations in disease progression is unelucidated. Methods: In this study, we combined scRNA-seq and bulk-level sequencing to analyze the transcriptomes of peripheral blood mononuclear cells from healthy volunteers and patients with septic ARDS (sep-ARDS) and pneumonic ARDS (PNE-ARDS). Results: Our data revealed differential alterations at the cellular and molecular levels and within biological signaling pathways in ARDS with different etiologies. The dynamics of neutrophils, macrophages (Macs), classical dendritic cells (cDCs), myeloid-derived suppressive cells (MDSCs), and CD8⁺ T cells varied significantly among groups of different samples, with neutrophils and cDCs at higher, and Macs at significantly lower, amounts in the patients with sep-ARDS. Furthermore, MDSCs were highly enriched only in the sep-ARDS patients, whereas a higher abundance of CD8⁺ T cells was observed in patients with PNE-ARDS. In addition, these cell subpopulations were found to be significantly involved in apoptosis, inflammatory, and immune-related pathways. In particular, a significant enhancement of the oxidative stress response was observed in the neutrophil subpopulation. Conclusion: Our study shows that the composition of cells involved in the main peripheral circulation differs in patients with ARDS with different etiologies. Studying the role and mechanism of action of these cells during ARDS will provide new opportunities for the treatment of this condition.

Septic shock in obstetrics: guidelines of the All-Russian public organization “Federation of Anesthesiologists and Reanimatologists”

The article reflects the main provisions of the clinical guidelines on septic shock in obstetrics, approved by the All-Russian public organization “Federation of Anesthesiologists-Resuscitators” in 2022. The relevance of the problem is associated with high mortality and morbidity rates from sepsis and septic shock in obstetrics. The main issues of etiology, pathogenesis, clinical picture, methods of laboratory and instrumental diagnostics, features of using the qSOFA, SOFA, MOEWS, SOS, MEWC, IMEWS scales for sepsis verification are consistently presented. The article presents the starting intensive therapy (the first 6–12 hours) of the treatment of septic shock in obstetrics, taking into account the characteristics of the pregnant woman's body. The strategy of prescribing vasopressors (norepinephrine, phenylephrine, epinephrine), inotropic drugs (dobutamine) is described, antibiotics and optimal antibiotic therapy regimens, features of infusion and adjuvant therapy are presented. The issues of surgical treatment of the focus of infection and indications for hysterectomy, as well as the organization of medical care and rehabilitation of patients with sepsis and septic shock were discussed. The basic principles of prevention of sepsis and septic shock in obstetrics are described. The criteria for the quality of medical care for patients with septic shock and the algorithms of doctor's actions in the diagnosis and intensive care of patients with septic shock in obstetrics are presented.

Procyanidin B2 Attenuates Sepsis-Induced Acute Lung Injury via Regulating Hippo/Rho/PI3K/NF-κB Signaling Pathway

Acute lung injury (ALI) is a frequent and challenging aspect of sepsis that currently lacks effective treatments. Procyanidin B2 (PB2) has anti-inflammatory and antioxidant properties. The aim of this study was to determine the effectiveness and mechanism of action of PB2 in treating sepsis-induced ALI using animal experiments. A sepsis-induced ALI mouse model was used by administering lipopolysaccharide (LPS) and then evaluating the levels of inflammatory cytokines and lung injury through measurements of cytokine levels using enzyme-linked immunosorbent assay (ELISA), Western blot and real-time PCR, as well as by the examination of relevant signaling pathways. The animal experiments showed that PB2 protected the lungs from injury caused by LPS and reduced the levels of various inflammatory cytokines in both the serum and lung tissue. Western blot analysis showed that PB2 reduced the expression of TLR4/NF-κB and increased the expression of PI3K/Akt, and also inhibited the Hippo and Rho signaling pathways. The results of the study showed that PB2 helps to treat sepsis-induced ALI by controlling cytokine storms and reducing inflammation by altering the expressions of the TLR4/NF-κB, PI3K/Akt, Hippo and Rho signaling pathways. This research provides a foundation for the further investigation of PB2's mechanism and its potential use in treating sepsis.

Clinical outcomes after a single induction dose of etomidate versus ketamine for emergency department sepsis intubation: a randomized controlled trial

Patients with sepsis often require emergency intubation. In emergency departments (EDs), rapid-sequence intubation with a single-dose induction agent is standard practice, but the best choice of induction agent in sepsis remains controversial. We conducted a randomized, controlled, single-blind trial in the ED. We included septic patients who were aged at least 18 years and required sedation for emergency intubation. Patients were randomly assigned by a blocked randomization to receive 0.2-0.3 mg/kg of etomidate or 1-2 mg/kg of ketamine for intubation. The objectives were to compare the survival outcomes and adverse events after intubation between etomidate and ketamine. Two hundred and sixty septic patients were enrolled; 130 patients/drug arm whose baseline characteristics were well balanced at baseline. In the etomidate group, 105 patients (80.8%) were alive at 28 days, compared with 95 patients (73.1%) in the ketamine group (risk difference [RD], 7.7%; 95% confidence interval [CI], - 2.5 to 17.9%; P = 0.092). There was no significant difference in the proportion of patients who survived at 24 h (91.5% vs. 96.2%; P = 0.097) and survived at 7 days (87.7% vs. 87.7%; P = 0.574). A significantly higher proportion of the etomidate group needed a vasopressor within 24 h after intubation: 43.9% vs. 17.7%, RD, 26.2% (95% CI, 15.4 to 36.9%; P < 0.001). In conclusion, there were no differences in early and late survival rates between etomidate and ketamine. However, etomidate was associated with higher risks of early vasopressor use after intubation. Trial registration: The trial protocol was registered in the Thai Clinical Trials Registry (identification number: TCTR20210213001). Registered 13 February 2021-Retrospectively registered, https://www.thaiclinicaltrials.org/export/pdf/TCTR20210213001 .

Combined Multiomics and In Silico Approach Uncovers PRKAR1A as a Putative Therapeutic Target in Multi-Organ Dysfunction Syndrome

Despite all epidemiological, clinical, and experimental research efforts, therapeutic concepts in sepsis and sepsis-induced multi-organ dysfunction syndrome (MODS) remain limited and unsatisfactory. Currently, gene expression data sets are widely utilized to discover new biomarkers and therapeutic targets in diseases. In the present study, we analyzed MODS expression profiles (comprising 13 sepsis and 8 control samples) retrieved from NCBI-GEO and found 359 differentially expressed genes (DEGs), among which 170 were downregulated and 189 were upregulated. Next, we employed the weighted gene co-expression network analysis (WGCNA) to establish a MODS-associated gene co-expression network (weighted) and identified representative module genes having an elevated correlation with age. Based on the results, a turquoise module was picked as our hub module. Further, we constructed the PPI network comprising 35 hub module DEGs. The DEGs involved in the highest-confidence PPI network were utilized for collecting pathway and gene ontology (GO) terms using various libraries. Nucleotide di- and triphosphate biosynthesis and interconversion was the most significant pathway. Also, 3 DEGs within our PPI network were involved in the top 5 significantly enriched ontology terms, with hypercortisolism being the most significant term. PRKAR1A was the overlapping gene between top 5 significant pathways and GO terms, respectively. PRKAR1A was considered as a therapeutic target in MODS, and 2992 ligands were screened for binding with PRKAR1A. Among these ligands, 3 molecules based on CDOCKER score (molecular dynamics simulated-based score, which allows us to rank the binding poses according to their quality and to identify the best pose for each system) and crucial interaction with human PRKAR1A coding protein and protein kinase-cyclic nucleotide binding domains (PKA RI alpha CNB-B domain) via active site binding residues, viz. Val283, Val302, Gln304, Val315, Ile327, Ala336, Ala337, Val339, Tyr373, and Asn374, were considered as lead molecules.

Cytokine-Mediated Degradation of the Transcription Factor ERG Impacts the Pulmonary Vascular Response to Systemic Inflammatory Challenge

Background

During infectious diseases, pro-inflammatory cytokines transiently destabilize interactions between adjacent vascular endothelial cells (ECs) to facilitate the passage of immune molecules and cells into tissues. However, in the lung the resulting vascular hyperpermeability can lead to organ dysfunction. Previous work identified the transcription factor ERG as a master regulator of endothelial homeostasis. Here we investigate whether the sensitivity of pulmonary blood vessels to cytokine-induced destabilization is due to organotypic mechanisms affecting the ability of endothelial ERG to protect lung ECs from inflammatory injury.

Methods

Cytokine-dependent ubiquitination and proteasomal degradation of ERG was analyzed in cultured Human Umbilical Vein ECs (HUVECs). Systemic administration of TNFα or the bacterial cell wall component lipopolysaccharide (LPS) was used to cause a widespread inflammatory challenge in mice; ERG protein levels were assessed by immunoprecipitation, immunoblot, and immunofluorescence. Murine Erg deletion was genetically induced in ECs ( Erg fl/fl ;Cdh5(PAC)Cre ERT2 ), and multiple organs were analyzed by histology, immunostaining, and electron microscopy.

Results

In vitro, TNFα promoted the ubiquitination and degradation of ERG in HUVECs, which was blocked by the proteasomal inhibitor MG132. In vivo, systemic administration of TNFα or LPS resulted in a rapid and substantial degradation of ERG within lung ECs, but not ECs of the retina, heart, liver, or kidney. Pulmonary ERG was also downregulated in a murine model of influenza infection. Erg fl/fl ;Cdh5(PAC)-Cre ERT2 mice spontaneously recapitulated aspects of inflammatory challenges, including lung-predominant vascular hyperpermeability, immune cell recruitment, and fibrosis. These phenotypes were associated with a lung-specific decrease in the expression of Tek , a gene target of ERG previously implicated in maintaining pulmonary vascular stability during inflammation.

Conclusions

Collectively, our data highlight a unique role for ERG in pulmonary vascular function. We propose that cytokine-induced ERG degradation and subsequent transcriptional changes in lung ECs play critical roles in the destabilization of pulmonary blood vessels during infectious diseases.

Huashibaidu formula attenuates sepsis-induced acute lung injury via suppressing cytokine storm: Implications for treatment of COVID-19

BACKGROUND

Acute lung injury (ALI) is a common complication of sepsis with poor effective interventions. Huashibaidu formula (HSBD) showed good therapeutic effects in treating coronavirus disease 2019 (COVID-19) patients.

PURPOSE

This study was designed to investigate the therapeutic potential and precise mechanism of HSBD against sepsis-induced ALI based on network pharmacology and animal experiments.

MATERIALS AND METHODS

Network pharmacology was used to predict the possible mechanism of HSBD against sepsis. Next, a sepsis-induced ALI rat model via intraperitoneal lipopolysaccharide (LPS) was constructed to evaluate the level of inflammatory cytokines and the degree of lung injury. The expression of inflammation-related signaling pathways, including TLR4/NF-κB and PI3K/Akt was determined by western blot.

RESULTS

Network pharmacology analysis indicated that HSBD might have a therapeutic effect on sepsis mainly by affecting inflammatory and immune responses. Animal experiments demonstrated that HSBD protected the lung tissue from LPS-induced injury, and inhibited the levels of inflammatory cytokines such as interleukin (IL)-1β, granulocyte-macrophage colony-stimulating factor (GM-CSF), interferon (IFN)-γ and tumor necrosis factor (TNF)-α in the serum and IL-1β, IL-5, IL-6, IL-18, GM-CSF, IFN-γ and TNF-α in the lung tissue. Western blot results revealed that HSBD downregulated the expression of TLR4/NF-κB and upregulated the expression of PI3K/Akt.

CONCLUSION

The therapeutic mechanism of HSBD against sepsis-induced ALI mainly involved suppressing cytokine storms and relieving inflammatory symptoms by regulating the expression of TLR4/NF-κB and PI3K/Akt. Our study provides a scientific basis for the mechanistic investigation and clinical application of HSBD in the treatment of sepsis and COVID-19.

Septic Shock: Management and Outcomes

The incidence rates of sepsis and septic shock as a complication have become more common over the past several decades. With this increase, sepsis remains the most common cause of intensive care unit (ICU) admissions and one of the most mortality factors, with a huge burden on healthcare facilities. Septic shock has devastating consequences on patients' lives, including organ failures and other long-term complications. Due to its dynamic clinical presentations, guidelines and tools have been established to improve the diagnosis and management effectively. However, there is still a need for evidence-based standardized procedures for the diagnosis, treatment, and follow-up of sepsis and septic shock patients due to the inconsistency of current guidelines and studies contrasting with each other. The standardization would help physicians better manage sepsis, minimize complications and reduce mortality. Septic shock is usually challenging to manage due to its variety of clinical characteristics and physiologic dynamics, affecting the outcomes. Therefore, this review presented the available data in the literature on septic shock diagnosis, management, and prognosis to have an overview of the updated best practice approach to septic shock.

Assessing organ-level immunoreactivity in a rat model of sepsis using TSPO PET imaging

There is current need for new approaches to assess/measure organ-level immunoreactivity and ensuing dysfunction in systemic inflammatory response syndrome (SIRS) and sepsis, in order to protect or recover organ function. Using a rat model of systemic sterile inflammatory shock (intravenous LPS administration), we performed PET imaging with a translocator protein (TSPO) tracer, [¹⁸F]DPA-714, as a biomarker for reactive immunoreactive changes in the brain and peripheral organs. In vivo dynamic PET/CT scans showed increased [¹⁸F]DPA-714 binding in the brain, lungs, liver and bone marrow, 4 hours after LPS injection. Post-LPS mean standard uptake values (SUV_mean) at equilibrium were significantly higher in those organs compared to baseline. Changes in spleen [¹⁸F]DPA-714 binding were variable but generally decreased after LPS. SUV_mean values in all organs, except the spleen, positively correlated with several serum cytokines/chemokines. In vitro measures of TSPO expression and immunofluorescent staining validated the imaging results. Noninvasive molecular imaging with [¹⁸F]DPA-714 PET in a rat model of systemic sterile inflammatory shock, along with in vitro measures of TSPO expression, showed brain, liver and lung inflammation, spleen monocytic efflux/lymphocytic activation and suggested increased bone marrow hematopoiesis. TSPO PET imaging can potentially be used to quantify SIRS and sepsis-associated organ-level immunoreactivity and assess the effectiveness of therapeutic and preventative approaches for associated organ failures, in vivo.

Sex-related differences in the response of anti-platelet drug therapies targeting purinergic signaling pathways in sepsis

Sepsis, a complex clinical syndrome resulting from a serious infection, is a major healthcare problem associated with high mortality. Sex-related differences in the immune response to sepsis have been proposed but the mechanism is still unknown. Purinergic signaling is a sex-specific regulatory mechanism in immune cell physiology. Our studies have shown that blocking the ADP-receptor P2Y12 but not P2Y1 receptor was protective in male mice during sepsis, but not female. We now hypothesize that there are sex-related differences in modulating P2Y12 or P2Y1 signaling pathways during sepsis. Male and female wild-type (WT), P2Y12 knock-out (KO), and P2Y1 KO mice underwent sham surgery or cecal ligation and puncture (CLP) to induce sepsis. The P2Y12 antagonist ticagrelor or the P2Y1 antagonist MRS2279 were administered intra-peritoneally after surgery to septic male and female mice. Blood, lungs and kidneys were collected 24 hours post-surgery. Sepsis-induced changes in platelet activation, secretion and platelet interaction with immune cells were measured by flow cytometry. Neutrophil infiltration in the lung and kidney was determined by a myeloperoxidase (MPO) colorimetric assay kit. Sepsis-induced platelet activation, secretion and aggregate formation were reduced in male CLP P2Y12 KO and in female CLP P2Y1 KO mice compared with their CLP WT counterpart. Sepsis-induced MPO activity was reduced in male CLP P2Y12 KO and CLP P2Y1 KO female mice. CLP males treated with ticagrelor or MRS2279 showed a decrease in sepsis-induced MPO levels in lung and kidneys, aggregate formation, and platelet activation as compared to untreated male CLP mice. There were no differences in platelet activation, aggregate formation, and neutrophil infiltration in lung and kidney between female CLP mice and female CLP mice treated with ticagrelor or MRS2279. In human T lymphocytes, blocking P2Y1 or P2Y12 alters cell growth and secretion in vitro in a sex-dependent manner, supporting the data obtained in mice. In conclusion, targeting purinergic signaling represents a promising therapy for sepsis but drug targeting purinergic signaling is sex-specific and needs to be investigated to determine sex-related targeted therapies in sepsis.

Use of CytoSorb© Hemoadsorption in Patients on Veno-Venous ECMO Support for Severe Acute Respiratory Distress Syndrome: A Systematic Review

Acute respiratory distress syndrome (ARDS) is associated with high morbidity and mortality. Adjunct hemoadsorption is increasingly utilized to target underlying hyperinflammation derived from ARDS. This article aims to review available data on the use of CytoSorb© therapy in combination with V-V ECMO in severe ARDS, and to assess the effects on inflammatory, laboratory and clinical parameters, as well as on patient outcomes. A systematic literature review was conducted and reported in compliance with principles derived from the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement. When applicable, a before-and-after analysis for relevant biomarkers and clinical parameters was carried out. CytoSorb© use was associated with significant reductions in circulating levels of C-reactive protein and interleukin-6 (p = 0.039 and p = 0.049, respectively). Increases in PaO2/FiO2 reached significance as well (p = 0.028), while norepinephrine dosage reductions showed a non-significant trend (p = 0.067). Mortality rates in CytoSorb© patients tended to be lower than those of control groups of most included studies, which, however, were characterized by high heterogeneity and low power. In an exploratory analysis on 90-day mortality in COVID-19 patients supported with V-V ECMO, the therapy was associated with a significantly reduced risk of death. Based on the reviewed data, CytoSorb© therapy is able to reduce inflammation and potentially improves survival in ARDS patients treated with V-V ECMO. Early initiation of CytoSorb© in conjunction with ECMO might offer a new approach to enhance lung rest and promote recovery in patients with severe ARDS.