Acute lung injury (ALI) is a significant complication of sepsis, characterized by high morbidity, mortality, and poor prognosis. Neutrophils, as critical intrinsic immune cells in the lung, play a fundamental role in the development and progression of ALI. During ALI, neutrophils generate neutrophil extracellular traps (NETs), and excessive NETs can intensify inflammatory injury. Research indicates that Taohe Chengqi decoction (THCQD) can ameliorate sepsis-induced lung inflammation and modulate immune function. This study aimed to investigate the mechanisms by which THCQD improves ALI and its relationship with NETs in sepsis patients, seeking to provide novel perspectives and interventions for clinical treatment. The findings demonstrate that THCQD enhanced survival rates and reduced lung injury in the cecum ligation and puncture (CLP)-induced ALI mouse model. Furthermore, THCQD diminished neutrophil and macrophage infiltration, inflammatory responses, and the production of pro-inflammatory cytokines, including interleukin-1β (IL-1β), IL-6, and tumor necrosis factor α (TNF-α). Notably, subsequent experiments confirmed that THCQD inhibits NET formation both in vivo and in vitro. Moreover, THCQD significantly decreased the expression of peptidyl arginine deiminase 4 (PAD4) protein, and molecular docking predicted that certain active compounds in THCQD could bind tightly to PAD4. PAD4 overexpression partially reversed THCQD's inhibitory effects on PAD4. These findings strongly indicate that THCQD mitigates CLP-induced ALI by inhibiting PAD4-mediated NETs.
Extracellular Traps/immunology* ; Acute Lung Injury/immunology* ; Animals ; Sepsis/immunology* ; Drugs, Chinese Herbal/pharmacology* ; Mice ; Neutrophils/immunology* ; Male ; Protein-Arginine Deiminase Type 4/genetics* ; Mice, Inbred C57BL ; Humans ; Disease Models, Animal ; Cytokines/metabolism*

Sepsis is a life-threatening organ dysfunction caused by a dysregulated host response to infection,with a high mortality rate.Sirtuin 3,a deacetylase within mitochondria,plays an important regulatory role in cellular metabolism,oxidative stress,and inflammatory responses.In recent years,significant progress has been made in the study of the function and regulatory role of sirtuin 3 in sepsis-related diseases.Research has shown that sirtuin 3 can alleviate organ damage caused by sepsis by regulating mitochondrial function,reducing oxidative stress,and inhibiting inflammatory responses.The specific mechanisms include the regulation of mitochondrial bioenergetics,activation of antioxidant enzyme systems,and inhibition of inflammatory mediator expression.In addition,sirtuin 3 plays a protective role in the pathological process of sepsis by interacting with multiple signaling pathways.This article summarizes the functions and regulatory mechanisms of sirtuin 3 in various sepsis-related diseases,aiming to provide new targets and strategies for the prevention and treatment of sepsis in the future.
Sepsis/metabolism* ; Sirtuin 3/physiology* ; Humans ; Animals ; Oxidative Stress ; Mitochondria/metabolism* ; Signal Transduction

OBJECTIVES: To investigate the expression of soluble factor-related apoptosis ligand (sFasL) in peripheral blood and microRNA-147b (miR-147b) in monocytes in children with sepsis and their value in assessing prognosis. METHODS: A prospective study was conducted on 124 children with sepsis (sepsis group), 60 children with common infections (infection group), and 60 healthy children undergoing physical examinations (healthy control group). The independent risk factors for poor prognosis in children with sepsis were analyzed, and the value of serum sFasL and monocyte miR-147b in predicting poor prognosis in children with sepsis was assessed. RESULTS: The serum level of sFasL and the relative expression of miR-147b in monocytes were highest in the sepsis group, followed by the infection group and the healthy control group (P<0.05). The multivariate logistic regression analysis showed that the serum level of sFasL and the relative expression of miR-147b in monocytes were closely associated with the poor prognosis of children with sepsis (P<0.05). The receiver operating characteristic curve analysis showed that the combination of serum sFasL level and relative expression of miR-147b in monocytes had a larger area under the curve compared to each indicator alone in predicting the prognosis of children with sepsis (P<0.05). CONCLUSIONS There are significant increases in the level of sFasL in peripheral blood and the relative expression of miR-147b in monocytes in children with sepsis. The combined use of these two indicators has relatively high clinical value in assessing the prognosis of children with sepsis.
Humans ; Sepsis/diagnosis* ; MicroRNAs/blood* ; Male ; Female ; Monocytes/metabolism* ; Prognosis ; Child, Preschool ; Prospective Studies ; Child ; Infant ; TNF-Related Apoptosis-Inducing Ligand/blood* ; Logistic Models

OBJECTIVE: To identify the underlying mechanism by which quercetin (Que) alleviates sepsis-related acute respiratory distress syndrome (ARDS). METHODS: In vivo, C57BL/6 mice were assigned to sham, cecal ligation and puncture (CLP), and CLP+Que (50 mg/kg) groups (n=15 per group) by using a random number table. The sepsisrelated ARDS mouse model was established using the CLP method. In vitro, the murine alveolar macrophages (MH-S) cells were classified into control, lipopolysaccharide (LPS), LPS+Que (10 μmol/L), and LPS+Que+acetylcysteine (NAC, 5 mmol/L) groups. The effect of Que on oxidative stress, inflammation, and apoptosis in mice lungs and MH-S cells was determined, and the mechanism with reactive oxygen species (ROS)/p38 mitogen-activated protein kinase (MAPK) pathway was also explored both in vivo and in vitro. RESULTS: Que alleviated lung injury in mice, as reflected by a reversal of pulmonary histopathologic changes as well as a reduction in lung wet/dry weight ratio and neutrophil infiltration (P<0.05 or P<0.01). Additionally, Que improved the survival rate and relieved gas exchange impairment in mice (P<0.01). Que treatment also remarkedly reduced malondialdehyde formation, superoxide dismutase and catalase depletion, and cell apoptosis both in vivo and in vitro (P<0.05 or P<0.01). Moreover, Que treatment diminished the release of inflammatory factors interleukin (IL)-1β, tumor necrosis factor-α, and IL-6 both in vivo and in vitro (P<0.05 or P<0.01). Mechanistic investigation clarifified that Que administration led to a decline in the phosphorylation of p38 MAPK in addition to the suppression of ROS expression (P<0.01). Furthermore, in LPS-induced MH-S cells, ROS inhibitor NAC further inhibited ROS/p38 MAPK pathway, as well as oxidative stress, inflammation, and cell apoptosis on the basis of Que treatment (P<0.05 or P<0.01). CONCLUSION Que was found to exert anti-oxidative, anti-inflammatory, and anti-apoptotic effects by suppressing the ROS/p38 MAPK pathway, thereby conferring protection for mice against sepsis-related ARDS.
Animals ; Sepsis/drug therapy* ; Quercetin/therapeutic use* ; Respiratory Distress Syndrome/enzymology* ; p38 Mitogen-Activated Protein Kinases/metabolism* ; Mice, Inbred C57BL ; Reactive Oxygen Species/metabolism* ; Apoptosis/drug effects* ; Male ; Oxidative Stress/drug effects* ; MAP Kinase Signaling System/drug effects* ; Lung/drug effects* ; Mice ; Lipopolysaccharides ; Macrophages, Alveolar/pathology* ; Inflammation/pathology* ; Protective Agents/therapeutic use*

OBJECTIVES: Sepsis-associated acute lung injury (S-ALI) is one of the major causes of death in intensive care unit (ICU) patients, yet its mechanisms remain incompletely understood and effective therapies are lacking. Lytic cell death of macrophages is a key driver of the inflammatory cascade in S-ALI. PANoptosis, a newly recognized form of lytic cell death characterized by PANoptosome assembly and activation, involves plasma membrane rupture (PMR) mediated by ninjurin-1 (NINJ1), a recently identified pore-forming protein. Itaconic acid is known for its anti-inflammatory effects, but its role in macrophage PANoptosis during S-ALI is unclear. This study aims to investigate the protective effect of itaconic acid on macrophage PANoptosis in S-ALI to provide new therapeutic insights. METHODS: Male specific-pathogen-free C57BL/6J mice (6-8 weeks, 18-20 g) received intraperitoneal lipopolysaccharide (LPS) to establish a classical S-ALI model. Western blotting was used to assess PANoptosome-related proteins and enzymes involved in the itaconic acid metabolic pathway, while real-time reverse transcription polymerase chain reaction and metabolomics quantified itaconic acid levels. Primary peritoneal macrophages (PMs) were pretreated with the itaconate derivative 4-octyl itaconate (4-OI) and then exposed to tumor necrosis factor alpha (TNF-α) plus interferon gamma (IFN-γ) to induce PANoptosis. Cell viability was evaluated by cell counting kit-8 (CCK-8) assay. Western blotting was employed to quantify enzymes of the itaconate-metabolic pathway in PANoptotic macrophages, to evaluate the impact of 4-OI on PANoptosome-associated proteins, and to determine NINJ1 abundance in lung tissues from S-ALI mice and in PANoptotic macrophages. Fluorescent dye FM_4-64 was used to visualize 4-OI-mediated changes in PMR, whereas immunofluorescence staining mapped the effect of 4-OI on both the expression level and membrane localization of NINJ1 in PANoptotic macrophages. The effect of 4-OI on lactate dehydrogenase (LDH) release in culture supernatants and peripheal blood serum was assessed using a LDH assay kit, and non-denataring polyacylamide gel electrophoresis was used to assess the expression of NINJ1 in S-ALI mouse lung tissues and the impact of 4-OI on the expression of PANoptosis-associated NINJ1 multimeric reflected protein in macropahges. RESULTS: In S-ALI mouse lungs, PANoptosome components [NOD-like receptor thermal protein domain associated protein 3 (NLRP3), Gasdermin D (GSDMD), Caspase-1, Z-DNA binding protein (ZBP1), and Caspase-3] and phosphorylated mixed lineage kinase domain-like protein (MLKL) S345 were significantly upregulated (all P<0.05), while metabolomics showed compensatory increases in itaconic acid and its key enzymes [aconitate decarboxylase 1 (ACOD1)/immunoresponsive gene 1 (IRG1)]. In macrophages, 4-OI obviously suppressed PANoptosome protein expression, reduced LDH release, restored plasma membrane integrity, and inhibited NINJ1 expression and oligomerization at the membrane (P<0.05). CONCLUSIONS Itaconic acid may alleviate macrophage PANoptosis in S-ALI by inhibiting NINJ1-mediated plasma membrane rupture. Targeting NINJ1 or enhancing itaconate pathways may offer a novel therapeutic strategy for S-ALI.
Animals ; Acute Lung Injury/pathology* ; Succinates/pharmacology* ; Sepsis/complications* ; Mice, Inbred C57BL ; Male ; Mice ; Macrophages/pathology* ; Cell Membrane/metabolism* ; Lipopolysaccharides ; Hydro-Lyases

OBJECTIVES: To evaluate the protective effect of Schistosoma japonicum cystatin (rSj-Cystatin) in a mouse mode of "two-hit" sepsis. METHODS: Sixty male C57BL/6 mice randomized equally into sham-operated group, protein group, "two-hit" modeling group, and protein intervention group. In the former two groups, the mice received an intraperitoneal injection of 100 μL PBS followed by exposure of the cecum and then by intraperitoneal injection of 100 μL PBS or 25 μg rSj-Cystatin 30 min later; In the latter two groups, 100 μL PBS containing LPS (5 mg/kg) was injected intraperitoneally 24 h before cecal ligation and puncture (CLP), and 100 μL PBS or 25 μg rSj-Cystatin were injected 30 min after CLP. At 12 h after rSj-Cystatin treatment, 6 mice from each group were sacrificed for detection of TNF-α, IL-6, IL-10, TGF-β, iNOS and Arg-1 in the serum, spleen, liver, lung and kidney tissues using ELISA, for examinations of liver, lung and kidney pathologies with HE staining, and for analysis of CD3⁺CD4⁺CD25⁺Foxp3⁺ T cell percentage in the spleen using flow cytometry. The remaining mice were observed for general condition and 72-h survival. RESULTS: The 72-h survival rates in the 4 groups were 100%, 100%, 0% and 20%, respectively, showing significant differences between the latter two groups. The mouse models of "two-hit" sepsis exhibited obvious tissue pathologies and significant elevations of TNF-α and IL-6 in both the serum and tissue homogenate, which were significantly ameliorated by rSj-Cystatin treatment. Treatment with rSj-Cystatin also increased IL-10 and TGF-β levels and spleen CD3⁺CD4⁺CD25⁺Foxp3⁺ T cell percentage. The septic mouse models also showed increased iNOS levels in all the detected tissues and a decreased Arg-1 level in the kidney, and these changes were obviously improved by rSj-Cystatin treatment. CONCLUSIONS rSj-Cystatin has a protective effect against "two-hit" sepsis in mice by regulating the inflammatory microenvironment.
Animals ; Mice ; Sepsis/drug therapy* ; Male ; Schistosoma japonicum/chemistry* ; Mice, Inbred C57BL ; Cystatins/therapeutic use* ; Interleukin-10/metabolism* ; Interleukin-6/blood* ; Tumor Necrosis Factor-alpha/blood* ; Disease Models, Animal ; Transforming Growth Factor beta/metabolism*

Microglial pyroptosis and neuroinflammation have been implicated in the pathogenesis of sepsis-associated encephalopathy (SAE). OGT-mediated O-GlcNAcylation is involved in neurodevelopment and injury. However, its regulatory function in microglial pyroptosis and involvement in SAE remains unclear. In this study, we demonstrated that OGT deficiency augmented microglial pyroptosis and exacerbated secondary neuronal injury. Furthermore, OGT inhibition impaired cognitive function in healthy mice and accelerated the progression in SAE mice. Mechanistically, OGT-mediated O-GlcNAcylation of ATF2 at Ser44 inhibited its phosphorylation and nuclear translocation, thereby amplifying NLRP3 inflammasome activation and promoting inflammatory cytokine production in microglia in response to LPS/Nigericin stimulation. In conclusion, this study uncovers the critical role of OGT-mediated O-GlcNAcylation in modulating microglial activity through the regulation of ATF2 and thus protects against SAE progression.
Animals ; Microglia/metabolism* ; Pyroptosis/physiology* ; Mice ; Sepsis-Associated Encephalopathy/prevention & control* ; Activating Transcription Factor 2/metabolism* ; N-Acetylglucosaminyltransferases/genetics* ; Mice, Inbred C57BL ; Male ; Mice, Knockout

Interleukin-18 (IL-18) and IL-37b have recently become a research hotspot because of their biological antagonistic role in inflammatory response. Sepsis is an abnormal inflammatory response-mediated life-threatening organ dysfunction induced by infection. Septic shock is the most severe form of sepsis, and has attracted great attention in clinical research due to its high mortality. Basophils are one of the classical effector cells in the inflammatory response, which are involved in many aspects of the pathological process of sepsis. IL-18 is an important pro-inflammatory cytokine and plays a key role in the inflammatory response, while IL-37b is known for its anti-inflammatory function. Both IL-18 and IL-37b can regulate the function of basophils and the inflammatory response in sepsis reversely through interleukin-18 receptor α (IL-18Rα). Therefore, it is of great clinical significance to investigate the role and mechanism of IL-18, IL-37b and basophils in the pathogenesis of sepsis. Herein, the relevant literatures on the roles and potential mechanisms of IL-18, IL-37b and basophils in the pathogenesis of sepsis are summarized, aiming to provide theoretical basis and novel ideas for the future research on the potential roles of IL-18, IL-37b and basophils in sepsis.
Humans ; Sepsis/immunology* ; Basophils/immunology* ; Interleukin-18/metabolism* ; Interleukin-1/metabolism* ; Animals

OBJECTIVE: To evaluate the risks and benefits of different resuscitation fluids in patients with early sepsis and septic shock by observing and comparing clinical indicators, clinical outcomes, and the concentration changes of glycocalyx biomarkers, and to determine how to appropriately select suitable resuscitation fluids for sepsis patients to aid fluid therapy. METHODS: A single center, prospective, randomized controlled trial was conducted. Patients with early sepsis and septic shock who have required fluid resuscitation after capacity status assessment admitted to the department of critical care medicine of Fourth Hospital of Hebei Medical University from April to October 2023 were enrolled. Patients were randomly assigned to either the experimental group (balanced crystalloid solution+albumin) or the control group (balanced crystalloid solution) by a random number table method. Clinical data of both groups of patients before and after resuscitation at 3, 8, and 24 hours were monitored, and blood samples were collected, enzyme-linked immunosorbent assay (ELISA) was used to measure the concentration of plasma glycocalyx biomarker syndecan-1. The 28-day and 90-day survival rates and complications were also assessed. RESULTS: A total of 66 patients were enrolled, including 44 in the experimental group and 22 in the control group. The baseline data of two groups were balanced and comparable. There was no statistically significant difference in the plasma concentration of syndecan-1 between the experimental group and the control group before and after resuscitation, and both showed a trend of first increasing and then decreasing. However, the plasma syndecan-1 level in the control group at 8 hours and 24 hours after resuscitation were significantly higher than the baseline level before resuscitation [ng/L: 19.02 (14.41, 27.80), 18.95 (12.40, 22.50) vs. 14.67 (11.57, 21.14), both P < 0.05], while there was no statistically significant difference at any time point within the experimental group. The correlation analysis between plasma syndecan-1 level and lactic acid, albumin, and sequential organ failure assessment (SOFA) in all patients showed that a positive correlation between syndecan-1 level and SOFA score before resuscitation (r = 0.247, P = 0.046), and a negative correlation between syndecan-1 level and albumin level at 24 hours after resuscitation (r = -0.308, P = 0.012). There were no statistically significant differences in 28-day and 90-day mortality, length of hospital stay, length of intensive care unit (ICU) stay, duration of mechanical ventilation, blood purification time, number of organ injuries, and complications between the two groups. However, the baseline albumin level in the experimental group was significantly lower than that in the control group (g/L: 28.7±4.5 vs. 31.6±4.2, P < 0.05). Analysis of clinical treatment data showed that compared with the control group, the experimental group had lower absolute lactate level at 8 hours and 24 hours after resuscitation [mmol/L: 8 hours was 1.30 (1.00, 1.88) vs. 1.60 (1.30, 3.05), 24 hours was 1.15 (0.80, 1.78) vs. 1.55 (1.08, 2.05), both P < 0.05], and higher lactate clearance rate [8 hours was 45% (27%, 56%) vs. 20% (-4%, 46%), 24 hours was 55% (34%, 70%) vs. 34% (-14%, 59%), both P < 0.05]. However, there were no statistically significant differences in the amount of fluid resuscitation, use of vasoactive drugs, and oxygenation index between the two groups during the resuscitation process. Multivariate Logistic regression analysis showed that body mass index (BMI) was independently correlated with 90-day mortality [odds ratio (OR) = 1.991, 95% confidence interval (95%CI) was 1.023-3.387, P = 0.043]. CONCLUSIONS There are no significant difference in plasma syndecan-1 level during fluid resuscitation of early sepsis and septic shock patients using balanced crystalloid fluid and balanced crystalloid fluid combined with albumin resuscitation, and there are no statistically significant differences in the impact on 28-day and 90-day prognosis, length of hospital stay, complications, and other aspects of the patients. However, compared to balanced crystalloid fluid, the combination of balanced crystalloid fluid and albumin for fluid resuscitation in sepsis patients has lower lactate level and better lactate clearance effect, but further validation is still needed through large-scale randomized controlled trials.
Humans ; Clinical Relevance ; Crystalloid Solutions/administration & dosage* ; Fluid Therapy/methods* ; Glycocalyx/metabolism* ; Isotonic Solutions/administration & dosage* ; Prospective Studies ; Resuscitation/methods* ; Sepsis/therapy* ; Shock, Septic/therapy* ; Syndecan-1/blood*

Sepsis is a common clinical syndrome in intensive care unit (ICU) with high morbidity and high mortality, making it a global health issue. The estimated global incidence of sepsis is 437/100 000, with an in-hospital mortality of 17%, which is higher in developing countries and underdeveloped regions. Despite some progress in sepsis treatment in recent years, the complexity of its pathophysiology limits therapeutic effectiveness. The cholinergic anti-inflammatory pathway (CAP), a neuro-immune regulatory pathway, plays a crucial role in sepsis through key components such as the vagus nerve, central M-type muscarinic receptor, the spleen and splenic sympathetic nerves, acetylcholine, and the α7 subunit of the nicotinic acetylcholine receptor (α7nAChR). This article explores the potential mechanisms and roles of CAP in sepsis, focusing on CAP-related cell signaling pathways, including nuclear factor-κB (NF-κB) signaling pathway, Janus kinase/signal transducer and activator of transcription 3 (JAK/STAT3) signaling pathway, phosphatidylinositol 3-kinase/protein kinase B (PI3K/Akt) signaling pathway, and cyclooxygenase (COX) and prostaglandin E2 (PGE2) signaling pathways. Potential applications of CAP in sepsis treatment include stimulating the vagus nerve (e.g., through pharmacological, electrical, or acupuncture stimulation), using α7nAChR agonists (e.g., nicotine, GTS-21, and PNU-282987), adrenergic receptor agonists (e.g., dexmedetomidine and salbutamol), or other drugs and bioactive substances (e.g., buprenorphine and traditional Chinese medicine components). These approaches aim to activate CAP, suppress inflammatory responses, and improve sepsis prognosis, providing a theoretical basis for treatment and promoting the development of related drugs.
Sepsis/metabolism* ; Humans ; Signal Transduction ; alpha7 Nicotinic Acetylcholine Receptor ; NF-kappa B/metabolism* ; Anti-Inflammatory Agents ; Acetylcholine