Dual-responsive renal injury cells targeting nanoparticles for vitamin E delivery to treat ischemia reperfusion-induced acute kidney injury.

Ischemia/reperfusion (I/R) is an important inducer of acute kidney injury (AKI), and triggers the generation of reactive oxygen species (ROS) and the expression of matrix metalloproteinase 2 (MMP2), exacerbating kidney damage. Given the immense potential of vitamin E (VitE) as a natural fat-soluble antioxidant in kidney protection, we designed the nanoparticles (NPs) that could dual respond to ROS and MMP2, aiming to accurately deliver VitE to renal injury cells. The NPs utilized Gel-SH as a sensitive receptor for MMP2 and diselenide as a sensitive receptor for ROS, while PEG2k modification enhanced biocompatibility and prevented phagocytosis mediated by the mononuclear phagocyte system. The amphiphilic Gel-SH and diselenide encapsulate the liposoluble VitE and self-assemble into the NPs with a hydrodynamic size of 69.92 nm. Both in vivo and in vitro experiments based on these NPs show good biocompatibility and the ability of target renal injury cells. In vivo kidney I/R injury models and in vitro cell hypoxia/reoxygenation models, the NPs have demonstrated effects in reducing oxidative stress and alleviating AKI. Notably, VitE can preferentially react with peroxyl radical (LOO•) than polyunsaturated fatty acid (PUFA), inhibiting the formation of carbon centered radical (L•), thereby blocking the chain reaction between PUFA and LOO• in ferroptosis. The NPs also inhibit the transition from AKI to chronic kidney disease, with few side effects. Thus, the NPs with dual-responsiveness to MMP2 and ROS for targeted delivery of VitE to renal injury cells exhibit remarkable effects in inhibiting ROS and the chain reactions of ferroptosis, making it a promising therapeutic agent against AKI caused by I/R.

Decitabine-based treatment strategy improved the outcome of HSCT in JMML: a retrospective cohort study.

Introduction: Pre-HSCT disease control, suboptimal long-term prognosis, and a high recurrence incidence (RI) continue to pose significant challenges for hematopoietic stem cell transplantation (HSCT) in juvenile myelomonocytic leukemia (JMML) patients. Methods: This retrospective cohort study assessed the effectiveness of a decitabine (DAC)-based protocol in JMML patients undergoing HSCT. The pre-HSCT treatment includes initial and bridging treatment. The efficacy of DAC monotherapy versus DAC combined with cytotoxic chemotherapy(C-DAC) as initial treatment was compared, followed by DAC plus FLAG (fludarabine, cytarabine, and GCSF) as bridging treatment. The HSCT regimens were based on DAC, fludarabine, and busulfan. Post-HSCT, low-dose DAC was used as maintenance therapy. The study endpoints focused on pretransplantation simplified clinical response and post-HSCT survival. Results: There were 109 patients, including 45 receiving DAC monotherapy and 64 undergoing C-DAC treatment. 106 patients completed bridging treatment. All patients were administered planned HSCT regimens and post-HSCT treatment. The initial treatment resulted in 88.1% of patients achieving clinical remission without a significant difference between the DAC and C-DAC groups (p=0.769). Clinical remission rates significantly improved following bridging treatment (p=0.019). The 5-year overall survival, leukemia-free survival, and RI were 92.2%, 88.4%, and 8.0%, respectively. A poor clinical response to pre-HSCT treatment emerged as a risk factor for OS (hazard ratio: 9.8, 95% CI: 2.3-41.1, p=0.002). Conclusion: Implementing a DAC-based administration strategy throughout the pre-HSCT period, during HSCT regimens, and in post-HSCT maintenance significantly reduced relapse and improved survival in JMML patients. Both DAC monotherapy and the DAC plus FLAG protocol proved effective as pre-HSCT treatments.

Palladium-Catalyzed Suzuki-Miyaura Reactions with Triazenyl-Tethered Aryl Bromides: Exploiting the Orthogonal Coupling Sites under Different Conditions.

Transition-metal-catalyzed cross-coupling of arenes bearing two or more potential coupling sites is often challenging because of the chemoselectivity issue. If orthogonal cross-couplings were applicable, one can develop a synthetically useful approach for consecutive functionalization of the starting arenes compounds. We herein reported a Suzuki-Miyaura coupling of triazenyl-substituted aryl bromides catalyzed by PdCl2(PCy3)2/PPh3 under basic conditions. The resultant polyfunctionalized aryl triazenes could undergo Suzuki-Miyaura couplings under acidic conditions or be converted to many other functionalized arenes. This orthogonal coupling strategy allows for a sequential functionalization of arenes with same type of nucleophilic reagents toward the synthesis of diverse biaryls and teraryls.

Exploring the role and therapeutic potential of lipid metabolism in acute kidney injury.

Acute kidney injury (AKI) is a prevalent condition, yet no specific treatment is available. Extensive research has revealed the pivotal role of lipid-related alterations in AKI. Lipid metabolism plays an essential role in the sustenance of the kidneys. In addition to their energy-supplying function, lipids contribute to the formation of renal biomembranes and the establishment of the renal microenvironment. Moreover, lipids or their metabolites actively participate in signal transduction, which governs various vital biological processes, such as proliferation, differentiation, apoptosis, autophagy, and epithelial-mesenchymal transition. While previous studies have focused predominantly on abnormalities in lipid metabolism in chronic kidney disease, this review focuses on lipid metabolism anomalies in AKI. We explore the significance of lipid metabolism products as potential biomarkers for the early diagnosis and classification of AKI. Additionally, this review assesses current preclinical investigations on the modulation of lipid metabolism in the progression of AKI. Finally, on the basis of existing research, this review proposes future directions, highlights challenges, and presents novel targets and innovative ideas for the treatment of and intervention in AKI.

Association between hyperglycemia at ICU admission and postoperative acute kidney injury in patients undergoing cardiac surgery: Analysis of the MIMIC-IV database.

Background: This study aimed to explore the correlation between hyperglycemia at intensive care unit (ICU) admission and the incidence of acute kidney injury (AKI) in patients after cardiac surgery. Methods: We conducted a retrospective cohort study, in which clinical data were extracted from the Medical Information Mart for Intensive Care (MIMIC)-IV database. Adults (≥18 years) in the database who were admitted to the cardiovascular intensive care unit after cardiac surgery were enrolled. The primary outcome was the incidence of AKI within 7 days following ICU admission. Secondary outcomes included ICU mortality, hospital mortality, ICU length of stay, and the 28-day and 90-day mortality. Multivariable Cox regression analysis was used to assess the association between ICU-admission hyperglycemia and AKI incidence within 7 days of ICU admission. Different adjustment strategies were used to adjust for potential confounders. Patients were divided into three groups according to their highest blood glucose levels recorded within 24 h of ICU admission: no hyperglycemia (<140 mg/dL), mild hyperglycemia (140-200 mg/dL), and severe hyperglycemia (≥200 mg/dL). Results: Of the 6905 included patients, 2201 (31.9%) were female, and the median (IQR) age was 68.2 (60.1-75.9) years. In all, 1836 (26.6%) patients had severe hyperglycemia. The incidence of AKI within 7 days of ICU admission, ICU mortality, and hospital mortality was significantly higher in patients with severe admission hyperglycemia than those with mild hyperglycemia or no hyperglycemia (80.3% vs. 73.6% and 61.2%, respectively; 2.8% vs. 0.9% and 1.9%, respectively; and 3.4% vs. 1.2% and 2.5%, respectively; all P <0.001). Severe hyperglycemia was a risk factor for 7-day AKI (Model 1: hazard ratio [HR]=1.4809, 95% confidence interval [CI]: 1.3126 to 1.6707; Model 2: HR=1.1639, 95% CI: 1.0176 to 1.3313; Model 3: HR=1.2014, 95% CI: 1.0490 to 1.3760; all P <0.050). Patients with normal glucose levels (glucose levels <140 mg/dL) had a higher 28-day mortality rate than those with severe hyperglycemia (glucose levels ≥200 mg/dL) (4.0% vs. 3.8%, P <0.001). Conclusions: In post-cardiac surgery patients, severe hyperglycemia within 24 h of ICU admission increases the risk of 7-day AKI, ICU mortality, and hospital mortality. Clinicians should be extra cautious regarding AKI among patients with hyperglycemia at ICU admission after cardiac surgery.

Macrophage migration inhibitory factor (MIF) suppresses mitophagy through disturbing the protein interaction of PINK1-Parkin in sepsis-associated acute kidney injury.

Damage to renal tubular epithelial cells (RTECs) signaled the onset and progression of sepsis-associated acute kidney injury (SA-AKI). Recent research on mitochondria has revealed that mitophagy plays a crucial physiological role in alleviating injury to RTECs and it is suppressed progressively by the inflammation response in SA-AKI. However, the mechanism by which inflammation influences mitophagy remains poorly understood. We examined how macrophage migration inhibitory factor (MIF), a pro-inflammatory protein, influences the PINK1-Parkin pathway of mitophagy by studying protein-protein interactions when MIF was inhibited or overexpressed. Surprisingly, elevated levels of MIF were found to directly bind to PINK1, disrupting its interaction with Parkin. This interference hindered the recruitment of Parkin to mitochondria and impeded the initiation of mitophagy. Furthermore, this outcome led to significant apoptosis of RTECs, which could, however, be reversed by an MIF inhibitor ISO-1 and/or a new mitophagy activator T0467. These findings highlight the detrimental impact of MIF on renal damage through its disruption of the interaction between PINK1 and Parkin, and the therapeutic potential of ISO-1 and T0467 in mitigating SA-AKI. This study offers a fresh perspective on treating SA-AKI by targeting MIF and mitophagy.

Identification of apoptosis-immune-related gene signature and construction of diagnostic model for sepsis based on single-cell sequencing and bulk transcriptome analysis.

Introduction: Sepsis leads to multi-organ dysfunction due to disorders of the host response to infections, which makes diagnosis and prognosis challenging. Apoptosis, a classic programmed cell death, contributes to the pathogenesis of various diseases. However, there is much uncertainty about its mechanism in sepsis. Methods: Three sepsis gene expression profiles (GSE65682, GSE13904, and GSE26378) were downloaded from the Gene Expression Omnibus database. Apoptosis-related genes were obtained from the Kyoto Encyclopedia of Genes and Genomes Pathway database. We utilized LASSO regression and SVM-RFE algorithms to identify characteristic genes associated with sepsis. CIBERSORT and single cell sequencing analysis were employed to explore the potential relationship between hub genes and immune cell infiltration. The diagnostic capability of hub genes was validated across multiple external datasets. Subsequently, the animal sepsis model was established to assess the expression levels of hub genes in distinct target organs through RT-qPCR and Immunohistochemistry analysis. Results: We identified 11 apoptosis-related genes as characteristic diagnostic markers for sepsis: CASP8, VDAC2, CHMP1A, CHMP5, FASLG, IFNAR1, JAK1, JAK3, STAT4, IRF9, and BCL2. Subsequently, a prognostic model was constructed using LASSO regression with BCL2, FASLG, IRF9 and JAK3 identified as hub genes. Apoptosis-related genes were closely associated with the immune response during the sepsis process. Furthermore, in the validation datasets, aside from IRF9, other hub genes demonstrated similar expression patterns and diagnostic abilities as observed in GSE65682 dataset. In the mouse model, the expression differences of hub genes between sepsis and control group revealed the potential impacts on sepsis-induced organ injury. Conclusion: The current findings indicated the participant of apoptosis in sepsis, and apoptosis-related differentially expressed genes could be used for diagnosis biomarkers. BCL2, FASLG, IRF9 and JAK3 might be key regulatory genes affecting apoptosis in sepsis. Our findings provided a novel aspect for further exploration of the pathological mechanisms in sepsis.

Thermodynamic Model for Hydrogen Production from Rice Straw Supercritical Water Gasification.

Supercritical water gasification (SCWG) technology is highly promising for its ability to cleanly and efficiently convert biomass to hydrogen. This paper developed a model for the gasification of rice straw in supercritical water (SCW) to predict the direction and limit of the reaction based on the Gibbs free energy minimization principle. The equilibrium distribution of rice straw gasification products was analyzed under a wide range of parameters including temperatures of 400-1200 °C, pressures of 20-50 MPa, and rice straw concentrations of 5-40 wt%. Coke may not be produced due to the excellent properties of supercritical water under thermodynamic constraints. Higher temperatures, lower pressures, and biomass concentrations facilitated the movement of the chemical equilibrium towards hydrogen production. The hydrogen yield was 47.17 mol/kg at a temperature of 650 °C, a pressure of 25 MPa, and a rice straw concentration of 5 wt%. Meanwhile, there is an absorptive process in the rice straw SCWG process for high-calorific value hydrogen production. Energy self-sufficiency of the SCWG process can be maintained by adding small amounts of oxygen (ER < 0.2). This work would be of great value in guiding rice straw SCWG experiments.

Tuning vibration-induced emission through macrocyclization and catenation.

In order to investigate the effect of macrocyclization and catenation on the regulation of vibration-induced emission (VIE), the typical VIE luminogen 9,14-diphenyl-9,14-dihydrodibenzo[a, c]phenazine (DPAC) was introduced into the skeleton of a macrocycle and corresponding [2]catenane to evaluate their dynamic relaxation processes. As investigated in detail by femtosecond transient absorption (TA) spectra, the resultant VIE systems revealed precisely tunable emissions upon changing the solvent viscosity, highlighting the key effect of the formation of [2]catenane. Notably, the introduction of an additional pillar[5]arene macrocycle featuring unique planar chirality endows the resultant chiral VIE-active [2]catenane with attractive circularly polarized luminescence in different states. This work not only develops a new strategy for the design of new luminescent systems with tunable vibration induced emission, but also provides a promising platform for the construction of smart chiral luminescent materials for practical applications.

Integrated Firefighting Textile with Temperature and Pressure Monitoring for Personal Defense.

Although electronic textiles that can detect external stimuli show great promise for fire rescue, existing firefighting clothing is still scarce for simultaneously integrating reliable early fire warning and real-time motion sensing, hardly providing intelligent personal protection under complex high-temperature conditions. Herein, we introduce an "all-in-one" hierarchically sandwiched fabric (HSF) sensor with a simultaneous temperature and pressure stimulus response for developing intelligent personal protection. A cross-arranged structure design has been proposed to tackle the serious mutual interference challenge during multimode sensing using two separate sets of core-sheath composite yarns and arrayed graphene-coated aerogels. The functional design of the HSF sensor not only possesses wide-range temperature sensing from 25 to 400 °C without pressure disturbance but also enables highly sensitive pressure response with good thermal adaptability (up to 400 °C) and wide pressure detection range (up to 120 kPa). As a proof of concept, we integrate large-scalable HSF sensors onto conventional firefighting clothing for passive/active fire warning and also detecting spatial pressure and temperature distribution when a firefighter is exposed to high-temperature flames, which may provide a useful design strategy for the application of intelligent firefighting protective clothing.

Simulation and analysis of chest loads on crews during Lunar-Earth re-entry returns.

The safety of crews is the primary concern in the manned lunar landing project, particularly during re-entry as the manned spacecraft returns from a direct Lunar-Earth trajectory. This paper analyzed the crew's chest biomechanical response to assess potential injuries caused by acceleration loads during the re-entry phase. Initially, a sophisticated finite element model of the chest was constructed, whose effectiveness was verified by experiments involving vertebral range of motion, rib lateral rupture, and chest frontal impact. The model was then subjected to the return re-entry loads simulating the Apollo and Chang'e 5 T1 (CE-5T1) test returner to specifically analyze the correlation between the acceleration load and the injury of the crew's chest tissues and organs. The results indicate that the biomechanical response of crew chest bone tissue under the two return missions is within the threshold value and will not directly cause damage. Compared to the Apollo mission, the CE-5T1 mission's load poses a higher risk to internal organs. These findings can enhance the crew's safety and provide reliable assurance for future space exploration.

TIMP2 protects against sepsis-associated acute kidney injury by cAMP/NLRP3 axis-mediated pyroptosis.

The tissue inhibitor of metalloproteinases 2 (TIMP2) has emerged as a promising biomarker for predicting the risk of sepsis-associated acute kidney injury (SA-AKI). However, its exact role in SA-AKI and the underlying mechanism remains unclear. In this study, we investigated the impact of kidney tubule-specific Timp2 knockout mice on kidney injury and inflammation. Our findings demonstrated that Timp2-knockout mice exhibited more severe kidney injury than wild-type mice, along with elevated levels of pyroptosis markers NOD-like receptor protein 3 (NLRP3), Caspase1, and gasdermin D (GSDMD) in the early stage of SA-AKI. Conversely, the expression of exogenous TIMP2 in TIMP2-knockout mice still protected against kidney damage and inflammation. In in vitro experiments, using recombinant TIMP2 protein, TIMP2 knockdown demonstrated that exogenous TIMP2 inhibited pyroptosis of renal tubular cells stimulated by lipopolysaccharide (LPS). Mechanistically, TIMP2 promoted the ubiquitination and autophagy-dependent degradation of NLRP3 by increasing intracellular cyclic adenosine monophosphate (cAMP), which mediated NLRP3 degradation through recruiting the E3 ligase MARCH7, attenuating downstream pyroptosis, and thus alleviating primary tubular cell damage. These results revealed the renoprotective role of extracellular TIMP2 in SA-AKI by attenuating tubular pyroptosis, and suggested that exogenous administration of TIMP2 could be a promising therapeutic intervention for SA-AKI treatment.NEW & NOTEWORTHY Tissue inhibitor of metalloproteinase 2 (TIMP-2) has been found to be the best biomarker for predicting the risk of sepsis-associated acute kidney injury (SA-AKI). However, its role and the underlying mechanism in SA-AKI remain elusive. The authors demonstrated in this study using kidney tubule-specific knockout mice model of SA-AKI and primary renal tubule cells stimulated with lipopolysaccharide (LPS) that extracellular TIMP-2 promoted NOD-like receptor protein 3 (NLRP3) ubiquitination and autophagy-dependent degradation by increasing intracellular cyclic adenosine monophosphate (cAMP), thus attenuated pyroptosis and alleviated renal damage.

Effect of Infusion Set Replacement Intervals on Central Line-Associated Bloodstream Infection in the Intensive Care Unit: Study Protocol of the INSPIRATION Study.

INTRODUCTION: The replacement intervals for infusion sets may differ among healthcare institutions, which may have an impact on the occurrence of central line-associated bloodstream infections (CLABSI). Nevertheless, there exists a limited amount of high-quality evidence available to assist clinicians in determining the most suitable replacement intervals for infusion sets. Therefore, the objective of this trial is to compare the efficacy of 24-h and 96-h replacement intervals for infusion sets on CLABSI among critically ill adults who have central venous access devices. METHODS: This is a multicenter, parallel-group randomized controlled trial that will investigate the effect of infusion set replacement intervals on CLABSI in adult patients admitted to intensive care units (ICUs). The study will enroll 1240 participants who meet the inclusion criteria, which includes being 18 years or older, expected to stay in the ICU for longer than 96 h, and in need of central venous access. Participants will be randomly assigned to either a control group receiving a 96-h replacement interval or a treatment group receiving a 24-h replacement interval. PLANNED OUTCOME: The primary outcome of this trial is the rate of CLABSI within 28 days after randomization. CONCLUSION: This is the first randomized controlled trial to investigate the effects of infusion set replacement at 24-h and 96-h intervals on CLABSI in ICU patients. TRIAL REGISTRATION: ClinicalTrials.gov identifier, NCT05359601.

ACETATE RINGER'S SOLUTION VERSUS NORMAL SALINE SOLUTION IN SEPSIS: A RANDOMIZED, CONTROLLED TRIAL.

ABSTRACT: Background: Normal saline solution (NSS) and Ringer's acetate solution (RAS) are commonly given to critically ill patients as a fundamental fluid therapy. However, the effect of RAS and NSS on sepsis patient outcomes remains unknown. Methods: We conducted a single-center prospective open-label parallel controlled trial to enroll adult patients (>18 years old) diagnosed with sepsis. Participants received either RAS or NSS for intravenous infusion for 5 days. The primary outcome was the incidence of major adverse kidney events within 28 days (MAKE28). Secondary outcomes included 30-/90-day mortality, acute kidney injury, and hyperchloremia. The patients were then reclassified as NSS-only, RAS-only, and RAS + NSS groups according to the type of fluid they had received before enrollment. Thereafter, a secondary post hoc analysis was performed. Results: Two hundred fifty-five septic patients were screened, and 143 patients (51.0% in RAS group and 49.0% in NSS group) were enrolled in the study. Each group received a median of 2 L of fluid administration during five interventional days. Of the patients, 39.3% had received 500 mL (500-1,000 mL) of balanced salt solutions (BSSs) before intensive care unit (ICU) admission. There was no statistical difference among the RAS and NSS group on the primary outcome MAKE28 in the initial analysis (23.3% vs. 20.0%; OR, 1.2 [0.6 to 2.2]; P = 0.69). MAKE28 was observed in 23.3% of RAS-only versus 27.3% of NSS-only group patients (0.82 [0.35-1.94], P = 0.65) in the secondary post hoc analysis. The patients in the NSS-only group had a longer invasive mechanical ventilation days and a trend toward the accumulation of serum chloride. Conclusion: This study observed no statistically significant difference on MAKE28 and secondary outcomes among sepsis patients receiving RAS and NSS. However, it is unclear whether the large amount of fluid resuscitation before ICU admission and carrier NSS narrowed the difference between BSSs and NSSs.

SAP130 released by ferroptosis tubular epithelial cells promotes macrophage polarization via Mincle signaling in sepsis acute kidney injury.

The pathological mechanism of sepsis-associated acute kidney injury (SA-AKI) is complex and involves tubular epithelial cell (TEC) death and immune cell activation. However, the interaction between tubular cell death and macrophage-mediated inflammation remains unclear. In this study, we uncovered that TEC ferroptosis was activated in SA-AKI. Increased levels of ferroptotic markers, including ferroptosis-related proteins, lipid peroxidation, malondialdehyde (MDA), 4-hydroxynonenal (4-HNE), reactive oxygen species (ROS), and mitochondrial damage, were observed in the kidney tissue of cecum ligation and puncture (CLP) and Lipopolysaccharide (LPS)-induced SA-AKI mouse models, which were subsequently suppressed by Ferrostatin-1 (Fer-1). In vitro experiments showed that Fer-1 inhibits LPS-induced mitochondrial damage, Fe2+ accumulation, and cytosolic ROS production. Moreover, it was found that TEC ferroptosis induced by promoted macrophage-inducible C-type lectin (Mincle) and its downstream expression and M1 polarization, which was mediated by the release of spliceosome-associated protein 130 (SAP130), an endogenous ligand of Mincle, from TEC. It was confirmed in vitro that the supernatant from LPS-stimulated TECs promoted Mincle expression and M1 polarization in macrophages. Further experiments revealed that M1 macrophages aggravated TEC ferroptosis, which was offset by neutralizing SAP130 or inhibiting Mincle expression. In addition, neutralizing the circulatory SAP130 blunted kidney ferroptosis and Mincle expression, as well as macrophage infiltration in the kidney of SA-AKI mice. In conclusion, the release of SAP130 from ferroptotic TECs promoted M1 macrophage polarization by triggering Mincle/syk/NF-κB signaling, and M1 macrophages, in turn, aggravated TEC ferroptosis.

Protein Kinase N1 Level Predicts Acute Kidney Injury in Patients Undergoing Cardiac Surgery: A Prospective Cohort Study.

INTRODUCTION: The objective of this study was to examine the utility of protein kinase N1 (PKN1) as a biomarker of cardiac surgery-associated AKI (CSA-AKI). METHODS: A prospective cohort study of 110 adults undergoing on-pump cardiac surgery was conducted. The associations between post-operative PKN1 and CSA-AKI, AKI severity, need for renal replacement therapy (RRT), duration of AKI, length of ICU stay, and post-operative hospital stay were evaluated. RESULTS: Patients were categorized into three groups according to PKN1 tertiles. The incidence of CSA-AKI in the third tertile was 3.4-fold higher than that in the first. PKN1 was an independent risk factor for CSA-AKI. The discrimination of PKN1 to CSA-AKI assessed by ROC curve indicated that the AUC was 0.70, and the best cutoff was 5.025 ng/mL. This group (>5.025 ng/mL) was more likely to develop CSA-AKI (p < 0.001). The combined AUC of EuroSCORE, aortic cross-clamp time, and PKN1 was 0.82 (p < 0.001). A higher level of PKN1 was related to increased need for RRT, longer duration of AKI, and length of ICU and post-operative hospital stays. CONCLUSIONS: PKN1 could be a potential biomarker for the prediction of CSA-AKI. The combination of PKN1, EuroSCORE, and aortic cross-clamp time was likely to predict the occurrence of CSA-AKI.

Fibroblastic reticular cell-derived exosomes are a promising therapeutic approach for septic acute kidney injury.

Sepsis-induced acute kidney injury (S-AKI) is highly lethal, and effective drugs for treatment are scarce. Previously, we reported the robust therapeutic efficacy of fibroblastic reticular cells (FRCs) in sepsis. Here, we demonstrate the ability of FRC-derived exosomes (FRC-Exos) to improve C57BL/6 mouse kidney function following cecal ligation and puncture-induced sepsis. In vivo imaging confirmed that FRC-Exos homed to injured kidneys. RNA-Seq analysis of FRC-Exo-treated primary kidney tubular cells (PKTCs) revealed that FRC-Exos influenced PKTC fate in the presence of lipopolysaccharide (LPS). FRC-Exos promoted kinase PINK1-dependent mitophagy and inhibited NLRP3 inflammasome activation in LPS-stimulated PKTCs. To dissect the mechanism underlying the protective role of Exos in S-AKI, we examined the proteins within Exos by mass spectrometry and found that CD5L was the most upregulated protein in FRC-Exos compared to macrophage-derived Exos. Recombinant CD5L treatment in vitro attenuated kidney cell swelling and surface bubble formation after LPS stimulation. FRCs were infected with a CD5L lentivirus to increase CD5L levels in FRC-Exos, which were then modified in vitro with the kidney tubular cell targeting peptide LTH, a peptide that binds to the biomarker protein kidney injury molecule-1 expressed on injured tubule cells, to enhance binding specificity. Compared with an equivalent dose of recombinant CD5L, the modified CD5L-enriched FRC-Exos selectively bound PKTCs, promoted kinase PINK-ubiquitin ligase Parkin-mediated mitophagy, inhibiting pyroptosis and improved kidney function by hindering NLRP3 inflammasome activation, thereby improving the sepsis survival rate. Thus, strategies to modify FRC-Exos could be a new avenue in developing therapeutics against kidney injury.

Explainable artificial intelligence model for mortality risk prediction in the intensive care unit: a derivation and validation study.

BACKGROUND: The lack of transparency is a prevalent issue among the current machine-learning (ML) algorithms utilized for predicting mortality risk. Herein, we aimed to improve transparency by utilizing the latest ML explicable technology, SHapley Additive exPlanation (SHAP), to develop a predictive model for critically ill patients. METHODS: We extracted data from the Medical Information Mart for Intensive Care IV database, encompassing all intensive care unit admissions. We employed nine different methods to develop the models. The most accurate model, with the highest area under the receiver operating characteristic curve, was selected as the optimal model. Additionally, we used SHAP to explain the workings of the ML model. RESULTS: The study included 21 395 critically ill patients, with a median age of 68 years (interquartile range, 56-79 years), and most patients were male (56.9%). The cohort was randomly split into a training set (N = 16 046) and a validation set (N = 5349). Among the nine models developed, the Random Forest model had the highest accuracy (87.62%) and the best area under the receiver operating characteristic curve value (0.89). The SHAP summary analysis showed that Glasgow Coma Scale, urine output, and blood urea nitrogen were the top three risk factors for outcome prediction. Furthermore, SHAP dependency analysis and SHAP force analysis were used to interpret the Random Forest model at the factor level and individual level, respectively. CONCLUSION: A transparent ML model for predicting outcomes in critically ill patients using SHAP methodology is feasible and effective. SHAP values significantly improve the explainability of ML models.

Bioinformatics reveals diagnostic potential of cuproptosis-related genes in the pathogenesis of sepsis.

Background: Multiple modes of cell death occur during the development of sepsis. Among these patterns, cuproptosis has recently been identified as a regulated form of cell death. However, its impact on the onset and progression of sepsis remains unclear. Method: We screened a dataset of gene expression profiles from patients with sepsis using the GEO database. Survival analysis was performed to analyze the relationship between cuproptosis-related genes (CRGs) and prognosis. Hub genes were identified through univariate Cox regression analysis. The diagnostic value of hub genes in sepsis was tested in both training sets (GSE65682) and validation sets (GSE134347). To examine the association between hub genes and immune cells, single-sample gene set enrichment analysis (ssGSEA) and Pearson correlation analysis were employed. Additionally, the CRGs were validated in a septic mouse model using real-time quantitative PCR (qRT-PCR) and immunohistochemistry (IHC). Results: In sepsis, most CRGs were upregulated, with only DLD and MTF1 downregulated. High expression of three genes (GLE, LIAS, and PDHB) was associated with better prognosis, but only two hub genes (LIAS, PDHB) reached statistical significance. The receiver operating characteristic (ROC) analysis for diagnosing sepsis showed LIAS had a range of 0.793-0.906, while PDHB achieved values of 0.882 and 0.975 in the training and validation sets, respectively. ssGSEA analysis revealed a lower number of immune cells in the sepsis group, and there was a correlation between immune cell population and CRGs (LIAS, PDHB). Analysis in the septic mouse model demonstrated no significant difference in mRNA expression levels and IHC staining between LIAS and PDHB in heart and liver tissues, but up-regulation was observed in lung tissues. Furthermore, the mRNA expression levels and IHC staining of LIAS and PDHB were down-regulated in renal tissues. Conclusions: Cuproptosis is emerging as a significant factor in the development of sepsis. LIAS and PDHB, identified as potential diagnostic biomarkers for cuproptosis-associated sepsis, are believed to play crucial roles in the initiation and progression of cuproptosis-induced sepsis.

Galectin-3 Mediates Endotoxin Internalization and Caspase-4/11 Activation in Tubular Epithelials and Macrophages During Sepsis and Sepsis-Associated Acute Kidney Injury.

Besides being recognized by membrane receptor TLR4, lipopolysaccharide (LPS) can also be internalized into the cytosol and activate Caspase-4/11 pyroptotic pathways to further amplify inflammation in sepsis. The objective of this study was to investigate whether Galectin-3 (Gal3) could promote the uptake of LPS by governing RAGE or administering endocytosis, consequently activating Caspase 4/11 and mediating pyroptosis in sepsis-associated acute kidney injury (SA-AKI). By pinpointing Gal3, LPS, and EEA1 (endosome-marker) or LAMP1 (lysosome-marker) respectively, immunofluorescence discovered that Gal3 and LPS were mainly aggregated in early endosomes initially and translocated into lysosomes afterwards. In cells and animal models, Gal3 and the Caspase-4/11 pathways were simultaneously activated, and the overexpression of Gal3 could exacerbate pyroptosis, whereas inhibition of Gal3 or the knockdown of its expression could ameliorate pyroptosis, reduce the pathological changes of SA-AKI and improve the survival of the animals with SA-AKI. Silencing RAGE reduced pyroptosis in primary tubular epithelial cells (PTCs) activated by Gal3 and LPS but not in cells activated by Gal3 and outer membrane vesicles (with LPS inside), whereas pyroptosis in both was reduced by blockade of Gal3, indicating Gal3 promoted pyroptosis through both RAGE-dependent and RAGE-independent pathways. Our investigation further revealed a positive correlation between serum Gal3 and pyroptotic biomarkers IL-1 beta and IL-18 in patients with sepsis, and that serum Gal3 was an independent risk factor for mortality. Through our collective exploration, we unraveled the significant role of Gal3 in the internalization of LPS and the provocation of more intense pyroptosis, thus making it a vital pathogenic factor in SA-AKI and a possible therapeutic target. Gal3 enabled the internalization of endotoxin into endosomes and lysosomes via both RAGE-dependent (A) and RAGE-independent (B) pathways, leading to pyroptosis. The suppression of Gal3 curbed Caspase4/11 noncanonical inflammasomes and diminished sepsis and SA-AKI.