OBJECTIVE: To elucidate the predictive value of norepinephrine equivalence (NEE) score on the 28-day death risk in patients with sepsis and provide evidence for its application in the diagnosis and treatment of sepsis and septic shock. METHODS: A retrospective cohort study was conducted based on the data of patients with sepsis from Medical Information Mart for Intensive Care-IV 2.2 (MIMIC-IV 2.2). The patients who received vasoactive agents within 6 hours after the diagnosis of sepsis or septic shock were enrolled, and they were divided into survival and non-survival groups based on their 28-day outcomes. The baseline characteristics, vital signs, and treatment data were collected. Multivariate Cox regression analysis was performed to identify factors influencing the 28-day death risk. Receiver operator characteristic curve (ROC curve) was drawn to analyze the predictive value of various parameters on the 28-day death risk of septic patients. Kaplan-Meier survival curve was used to evaluate cumulative survival rate in patients classified by different quantitative parameters based on the cut-off values obtained from ROC curve analysis. RESULTS: A total of 7 744 patients who met the Sepsis-3 diagnostic criteria and received vasopressor treatment within 6 hours post-diagnosis were enrolled, of which 5 997 cases survived and 1 747 died, with the 28-day mortality of 22.6%. Significant differences were observed between the two groups regarding age, gender, height, body weight, race, type of intensive care unit (ICU), acute physiology and chronic health evaluation II (APACHE II) score, sequential organ failure assessment (SOFA) score, Charlson comorbidity index (CCI) score, underlying comorbidities, and vital signs. Compared with the survival group, the non-survival group had poorer blood routine, liver and kidney function, coagulation function, blood gas analysis and other indicators. Multivariate Cox regression analysis revealed that age > 65 years old [hazard ratio (HR) = 0.892, 95% confidence interval (95%CI) was 0.801-0.994, P = 0.039] and male (HR = 0.735, 95%CI was 0.669-0.808, P < 0.001) were protective factors for 28-day death in patients with sepsis, and NEE score (HR = 1.040, 95%CI was 1.021-1.060, P < 0.001), shock index (HR = 1.840, 95%CI was 1.675-2.022, P < 0.001), APACHE II score (HR = 1.076, 95%CI was 1.069-1.083, P < 0.001), SOFA score (HR = 1.035, 95%CI was 1.015-1.056, P < 0.001), and CCI score (HR = 1.135, 95%CI was 1.115-1.155, P < 0.001) were independent risk factors for 28-day death in septic patients. ROC curve analysis showed that the area under the ROC curve (AUC) of NEE score for predicting the 28-day death risk of septic patients was 0.743 (95%CI was 0.730-0.756), which was comparable to the predictive value of APACHE II score (AUC = 0.742, 95%CI was 0.729-0.755) and ratio of mean arterial pressure (MAP)/NEE score (MAP/NEE; AUC = 0.738, 95%CI was 0.725-0.751, both P > 0.05), and better than SOFA score (AUC = 0.609, 95%CI was 0.594-0.624), CCI score (AUC = 0.658, 95%CI was 0.644-0.673), shock index (AUC = 0.613, 95%CI was 0.597-0.629) and ratio of diastolic blood pressure (DBP)/NEE score (DBP/NEE; AUC = 0.735, 95%CI was 0.721-0.748, all P < 0.05). According to the cut-off values of APACHE II and NEE scores obtained from ROC curve analysis, the patients were stratified for Kaplan-Meier survival curve analysis, and the results showed that the 28-day cumulative survival rate in the septic patients with an APACHE II score ≤ 22.5 was significantly higher than that in those with an APACHE II > 22.5 (Log-Rank test: χ² = 848.600, P < 0.001), and the 28-day cumulative survival rate in the septic patients with an NEE score ≤0.120 was significantly higher than that in those with an NEE score > 0.120 (Log-Rank test: χ² = 832.449, P < 0.001). CONCLUSIONS NEE score is an independent risk factor for 28-day death in septic patients who received vasoactive treatment within 6 hours of diagnosis and possesses significant predictive value. It can be used for severity stratification in sepsis management.
Humans ; Retrospective Studies ; Sepsis/diagnosis* ; Male ; Female ; Norepinephrine/therapeutic use* ; Middle Aged ; Aged ; Prognosis ; Predictive Value of Tests ; Shock, Septic/mortality* ; Adult ; ROC Curve ; Risk Factors ; Survival Rate ; Aged, 80 and over

OBJECTIVE: To investigate the incidence of sepsis in Xinjiang Uygur Autonomous Region and the compliance with sepsis diagnosis and treatment guidelines in intensive care unit (ICU) at different levels of hospitals, and to identify the risk factors associated with poor prognosis in patients with sepsis in this region. METHODS: A prospective cross-sectional survey was conducted in ICU of Xinjiang Uygur Autonomous Region Critical Care Medicine Alliance. The survey period was from 10:00 on January 31, 2024, to 09:59 on February 1, 2024. The patients diagnosed with sepsis admitted to the ICU during the study period were included in the analysis. Data on patient demographics, physiology, microbiology, and treatment protocols were collected, with follow-up until the 28th day after ICU admission or death. Baseline characteristics and treatment information of septic patients across different hospital levels were compared, as well as clinical data of septic patients with different 28-day outcomes. Multivariate Cox proportional hazards model was used to identify risk factors for 28-day death in septic patients. RESULTS: A total of 77 units of Xinjiang Uygur Autonomous Region Critical Care Medicine Alliance from 14 prefectures/cities in Xinjiang participated in the survey. On the survey day, 727 patients were admitted to ICU, of whom 179 (24.6%) were diagnosed with sepsis, and 64 (35.8%) died within 28 days, 115 (64.2%) survived. Among the participating institutions, 33 were tertiary hospitals (42.9%), managing 97 septic cases (54.2%), and 44 were secondary hospitals (57.1%), managing 82 septic cases (45.8%). The lactic acid monitoring rate and continuous renal replacement therapy (CRRT) rate for septic patients in tertiary hospitals were significantly higher than those in secondary hospitals [lactic acid monitoring rate: 92.8% (90/97) vs. 82.9% (68/82), CRRT rate: 17.5% (17/97) vs. 3.7% (3/82), both P < 0.05]. No statistically significant differences were observed between tertiary and secondary hospitals in length of ICU stay or 28-day mortality [length of ICU stay (days): 11.0 (16.0) vs. 10.0 (22.0), 28-day mortality: 35.1% (34/97) vs. 36.6% (30/82), both P > 0.05]. Compared with survivors, non-survivors had higher acute physiology and chronic health evaluation II (APACHE II) score, sequential organ failure assessment (SOFA) score, Charlson comorbidity index (CCI) score and lower Glasgow coma scale (GCS) score. Significant differences were noted in vital signs [heart rate, blood pressure, body temperature, pulse oxygen saturation (SpO₂)], laboratory markers [red blood cell count (RBC), white blood cell count (WBC), lymphocyte ratio (LYM%), blood urea nitrogen (BUN), total protein (TP), albumin (Alb), pH value, base excess (BE)], and monitoring, diagnosis and treatment information (invasive blood pressure monitoring, mechanical ventilation, CRRT, usage of norepinephrine). Multivariate Cox proportional hazards model indicated that body temperature [hazard ratio (HR) = 1.416, 95% confidence interval (95%CI) was 1.022-1.961, P = 0.037] and WBC (HR = 1.040, 95%CI was 1.010-1.071, P = 0.009) were independent risk factors for 28-day death in patients with sepsis. CONCLUSIONS Sepsis in Xinjiang Uygur Autonomous Region is characterized by a high mortality. In this region, tertiary hospitals demonstrate better compliance with bundled treatment strategies such as lactic acid monitoring and the usage of CRRT compared to secondary hospitals, yet they do not show significant advantages in clinical outcomes. Body temperature and WBC are independent risk factors for 28-day death in patients with sepsis in this region. However, clinicians should still consider the actual situation of patients, along with more optimal early warning indicators and comprehensive system assessments, to identify and prevent risk factors for adverse outcomes in patients.
Humans ; Sepsis/diagnosis* ; Cross-Sectional Studies ; Prospective Studies ; Risk Factors ; Intensive Care Units ; Prognosis ; China/epidemiology* ; Male ; Female ; Middle Aged ; Aged ; Proportional Hazards Models ; Incidence

Objective:To observe the effect of epigallocatechin gallate (EGCG) on intestinal injury in sepsis, and to investigate the effect on endoplasmic reticulum stress (ERS) apoptotic pathway.Methods:Sixty male SD rats were selected and divided into five groups according to the randomized numeric table method: the sham operation group (Sham group), the cecal ligation and puncture sepsis group (CLP group), the sepsis+EGCG low-dose group (postoperative intraperitoneal injection of EGCG 25 mg/kg, EL group), the sepsis+EGCG medium-dose group (postoperative intraperitoneal injection of EGCG 50 mg/kg, EM group), and sepsis+EGCG high-dose group (postoperative intraperitoneal injection of EGCG 75 mg/kg, EH group), each group with 12 rats. The rats in each group were executed 24 h after modeling and specimens were collected. Inflammatory factors in serum were detected by enzyme-linked immunosorbent assay. Pathological changes of ileum were observed under light microscope after hematoxylin eosin staining and evaluated according to the Chiu's score. The intestinal tissues were stained for tight junction protein-1 (CLDN1, Claudin-1), phosphorylated protein kinase R-like endoplasmic reticulum kinase (p-PERK), protein kinase RNA-like endoplasmic reticulum kinase (PERK), cysteinyl aspartate specific protein-12 (Caspase-12), and CCAAT enhancer-binding protein homologous protein (C/EBP-homologous protein antibody, CHOP) protein expression was detected by protein immunoblotting assay. The positive areas of Claudin-1, p-PERK, CHOP, and Caspase-12 in intestinal tissue were detected by immunohistochemistry.Results:Compared with the Sham group, the serum levels of interleukin (IL)-1β, IL-6, tumor necrosis factor-α, and the Chiu's score of rats in the CLP group were increased (all P<0.05). The ileal mucosal tissues showed reduced expression of Claudin-1, ERS apoptosis-associated protein p-PERK, CHOP, and Caspase-12 expression were increased (all P<0.05). Compared with the CLP group, the intestinal injury in rats was alleviated after the administration of low, medium and high dose EGCG intervention (all P<0.05). The serum inflammatory factor level, Chiu's score and the protein expression level and positive area of ERS apoptosis-related proteins, p-PERK, CHOP, and Caspase-12 in the small intestinal tissues of EL group were further reduced compared with that of the CLP group were further decreased, and EM group was further decreased than EL group, and EH group was further decreased than EM group (all P<0.05). The protein expression level and positive area of Claudin-1 in small intestinal tissues of EL group were further increased compared with that of CLP group (both P<0.05), and EM group was further increased compared with that of EL group and EH group was further increased compared with EM group (all P<0.05). Conclusions:EGCG may have a protective effect on intestinal injury in septic rats by inhibiting the activation of ERS-induced apoptotic pathway, and the efficacy of high-dose EGCG has a better effect.

Objective:To investigate the epidemiological characteristics of sepsis-associated encephalopathy (SAE) in patients with sepsis, analyze its risk factors and build a prediction model, which provides evidence for early clinical identification of SAE patients and improvement of clinical outcomes.Methods:A retrospective observational study was conducted. Sepsis patients admitted to the critical care medical center of the First Affiliated Hospital of Xinjiang Medical University from February 2022 to February 2023 were enrolled. According to whether SAE occurred, the patients were divided into sepsis group and SAE group. The 24 patients without sepsis in the same period were used as controls (non-sepsis group). Demographic data, relevant scores and laboratory test indicators at admission to intensive care unit (ICU), and prognostic indicators were collected. Univariate and multivariate Logistic regression analysis was used to analyze the risk factors for sepsis and SAE. Receiver operator characteristic curve (ROC curve) was drawn. The predictive value of each risk factor for sepsis and SAE.Results:A total of 130 patients with sepsis were included, of which 52 had SAE, and the incidence of SAE was 40.00%. There were significant differences in the length of ICU stay and total length of stay among all groups, while there were no significant differences in hospitalization cost and mechanical ventilation time. Multivariate Logistic regression analysis showed that pulmonary infection [odds ratio ( OR) = 46.817, 95% confidence interval (95% CI) was 5.624-389.757, P = 0.000], acute physiology and chronic health evaluation Ⅱ (APACHEⅡ: OR = 1.184, 95% CI was 1.032-1.358, P = 0.016), sequential organ failure assessment (SOFA: OR = 9.717, 95% CI was 2.618-36.068, P = 0.001), Charson comorbidity index (CCI: OR = 4.836, 95% CI was 1.860-12.577, P = 0.001), hemoglobin (Hb: OR = 0.893, 95% CI was 0.826-0.966, P = 0.005), glutamyltranspeptidase ( OR = 1.026, 95% CI was 1.008-1.045, P = 0.006) were independent risk factors for sepsis in ICU patients. Pulmonary infection ( OR = 28.795, 95% CI was 3.296-251.553, P = 0.002), APACHEⅡ score ( OR = 1.273, 95% CI was 1.104-1.467, P = 0.001), SOFA score ( OR = 8.670, 95% CI was 2.330-32.261, P = 0.001), CCI ( OR = 5.141, 95% CI was 1.961-13.475, P = 0.001), Hb ( OR = 0.922, 95% CI was 0.857-0.993, P = 0.031), glutamyltranspeptidase ( OR = 1.020, 95% CI was 1.002-1.038, P = 0.030) were independent risk factors for SAE in sepsis patients. ROC curve analysis showed that the area under the curve (AUC) of pulmonary infection, APACHEⅡ score, SOFA score, CCI, Hb, and glutamyltranspeptidase for predicting sepsis were 0.792, 0.728, 0.987, 0.933, 0.720, and 0.699, respectively; the AUC of the combined prediction of the above 6 variables for sepsis was 1.000, with a sensitivity of 100% and a specificity of 100%. The AUC predicted by pulmonary infection, APACHEⅡ score, SOFA score, CCI, and Hb for SAE were 0.776, 0.810, 0.907, 0.917, and 0.758, respectively; the AUC of the combined prediction of the above 5 variables for SAE was 0.975, with a sensitivity of 97.3% and a specificity of 93.1%. Conclusions:Sepsis is more severe when accompanied by encephalopathy. Pulmonary infection, Hb, APACHEⅡ score, SOFA score and CCI were independent risk factors of SAE. The combination of the above five indicators has good predictive value for early screening and prevention of the disease.

Objective:To construct a bundled therapy management and practice program for sepsis and explore its clinical application effect.Methods:① Construction of sepsis bundled therapy management and practice program: a project team was established to conduct literature review, select experts, compile and distribute questionnaires, organize, analyze expert opinions, and ensure quality control throughout the research process. From October to November 2022, expert letter consultation was carried out, and questionnaires were distributed and collected by on-site filling and WeChat. The Likert 5-point scale was used to rate each item. ② Clinical application of the protocol: ninety patients with sepsis admitted to the intensive care unit (ICU) of the First Affiliated Hospital of Xinjiang Medical University from January to July 2022 were retrospectively selected as the control group, and routine bundle treatment and nursing strategy for sepsis were adopted. Ninety patients with sepsis admitted from January to July 2023 were prospectively selected as the intervention group. Based on the treatment and nursing strategy of the control group, sepsis bundled therapy management and practice program constructed using the Delphi inquiry method was implemented. The completion rate of 1-hour, 3-hour and 6-hour bundle, the levels of inflammatory indicators at 1, 3, 7 days of treatment, and prognostic indicators were compared between the two groups.Results:① Construction of sepsis bundled therapy management and practice program: the final plan consists of 4 primary indicators, 15 secondary indicators and 34 tertiary indicators. The response rates for both rounds of inquiry questionnaires were 100%. The coefficients of expert authority value were 0.948 and 0.940, respectively. The coefficient of variation for each item was 0-0.287 and 0-0.187, respectively. Kendall's W coefficients were 0.242 and 0.249, respectively, with statistical significances (all P < 0.05). ② Clinical application of the protocol: there were no statistically significant differences in baseline data such as age, gender, infection site, pathogen species, duration of mechanical ventilation, sequential organ failure assessment (SOFA), acute physiology and chronic health evaluation Ⅱ (APACHEⅡ) between the two groups. The completion rate of 1-hour, 3-hour and 6-hour bundle in the intervention group were higher than those in the control group (1-hour bundle completion rate: 53.30% vs. 21.10%, 3-hour bundle completion rate: 92.20% vs. 80.00%, 6-hour bundle completion rate: 88.89% vs. 65.56%, all P < 0.05). The levels of C-reactive protein (CRP), white blood cell count (WBC), procalcitonin (PCT), and interleukin-6 (IL-6) in two groups of patients showed statistically significant differences at different time points, between groups, and in interaction effects. Compared with the control group, the length of ICU stay in the intervention group was significantly shortened [days: 7.00 (4.00, 14.00) vs. 8.00 (7.00, 20.00), P < 0.01], and the hospitalization cost of ICU was significantly reduced [ten thousand yuan: 4.63 (3.36, 6.19) vs. 6.46 (3.32, 11.34), P < 0.05]. The 28-day mortality in the intervention group was lower than that in the control group (33.33% vs. 46.67%), but the difference was not statistically significant ( P > 0.05). Conclusions:The constructed bundled therapy management and practice program for sepsis can improve the completion rate of bundle treatment, shorten the length of ICU stay of sepsis patients, reduce the hospitalization cost in ICU, and have a tendency to reduce the 28-day mortality.

Objective:To explore the protective effect and mechanism of acetate on sepsis-induced acute kidney injury (AKI) in rats.Methods:Male Sprague-Dawley (SD) rats were divided into sham operation group (Sham group), sepsis group caused by cecal ligation and puncture (CLP group), and acetate pretreatment group [NaA group, gavage sodium acetate (NaA) 300 mg/kg twice a day for 7 consecutive days before CLP] using a random number table method, with 7 rats in each group. The blood was taken from the main abdominal artery 24 hours after modeling, and renal tissue was collected from the rats. Enzyme linked immunosorbent assay (ELISA) was used to detect the serum levels of interleukin-6 (IL-6), tumor necrosis factor-α(TNF-α), and kidney injury molecule-1 (KIM-1). The concentration of serum acetate was determined by high performance liquid chromatography. The level of malondialdehyde (MDA) in renal tissue was detected by thiobarbituric acid method. Myeloperoxidase (MPO) in renal tissue was detected by colorimetric method. Hematoxylin-eosin (HE) staining was used to observe histopathological changes and assess renal tubule injury score. Western blotting was used to detect the protein expressions of G-protein coupled receptor 43 (GPR43) and adenosine monophosphate-activated protein kinase/silence infor-mation regulator 1/peroxlsome proliferator-activated receptor-γ coactlvator-1α (AMPK/SIRT1/PGC-1α) pathway. The positive expressions of GPR43, phosphorylation-AMPK (p-AMPK), SIRT1, PGC-1α were detected by immunohistochemistry.Results:Compared with Sham group, the serum levels of IL-6, TNF-α and KIM-1 were significantly increased in CLP group, the contents of MDA and MPO in renal tissue were increased, and the content of acetate was significantly decreased. HE staining results showed that most of the tubular epithelial cells were denaturated with local necrosis, a large number of brush border injuries and shedding, tubular structure destruction and fragmentation, and more inflammatory cells infiltrated the renal interstitium, the renal tubular injury score significantly increased. The expressions of GPR43, p-AMPK/AMPK, SIRT1, and PGC-1α in renal tissue were significantly reduced, indicating renal injury and increased levels of oxidative stress and inflammation in septic rats. Compared with the CLP group, the serum levels of IL-6, TNF-α and KIM-1 in the NaA group were decreased [IL-6 (ng/L): 126.20±6.23 vs. 161.00±17.37, TNF-α (ng/L): 85.59±7.70 vs. 123.50±17.78, KIM-1 (μg/L): 2.92±0.38 vs. 4.73±0.36, all P < 0.05]. The contents of MDA and MPO in renal tissue were significantly decreased [MDA (μmol/g): 6.56±0.18 vs. 8.53±0.34, MPO (U/g): 2.99±0.20 vs. 3.72±0.29, both P < 0.05]. HE staining showed that kidney injury had been alleviated, with a decrease in renal tubular injury score [1 (1, 2) vs. 3 (2, 3), P < 0.05]. Western blotting showed that the expressions of GPR43 and AMPK/SIRT1/PGC-1α pathway related proteins were significantly increased in renal tissue (GPR43/β-actin: 0.62±0.09 vs. 0.41±0.09, p-AMPK/AMPK: 0.58±0.07 vs. 0.44±0.06, SIRT1/β-actin: 0.85±0.06 vs. 0.73±0.03, PGC-1α/β-actin: 0.79±0.07 vs. 0.62±0.05, all P < 0.05). Immunohistochemistry showed that the positive expressions of GPR43, p-AMPK, SIRT1 and PGC-1α were significantly increased in renal tissue [GPR43 positive area: (33.66±2.62)% vs. (16.21±1.66)%, p-AMPK positive area: (16.64±2.11)% vs. (5.04±1.28)%, SIRT1 positive area: (14.61±2.86)% vs. (7.34±1.00)%, PGC-1α positive area: (15.30±2.39)% vs. (4.84±1.67)%, all P < 0.05], the serum acetate concentration significantly increased (μg/L: 32?479±14?683 vs. 12?935±3?197, P < 0.05). Conclusion:Acetate can ameliorate sepsis-induced AKI, the mechanism may be related to the activation of AMPK/SIRT1/PGC-1α pathway by GPR43.

Objective:To investigate whether silence information regulator 1 (SIRT1) could regulate nuclear factor E2-related factor 2/heme oxygenase 1 (Nrf2/HO-1) signaling pathway and its role in acute lung injury (ALI) in sepsis rats.Methods:Twenty-four male Sprague-Dawley (SD) rats were randomly divided into sham operation group (Sham group), cecal ligation and puncture (CLP) induced sepsis group (CLP group), sepsis+SIRT1 specific agonist group (CLP+SRT1720 group,10 mg/kg SRT1720 was intraperitoneally injected 2 hours before CLP), sepsis+SIRT1 specific inhibitor group (CLP+EX527 group, 10 mg/kg EX527 was intraperitoneally injected 2 hours before CLP), with 6 rats in each group. The rats were killed 24 hours after modeling and their lung tissues were taken for pathological score (Smith score), superoxide dismutase (SOD), glutathione (GSH), malondialdehyde (MDA), 8-hydroxydeoxyguanosine (8-OHdG), tumor necrosis factor-α (TNF-α), interleukins (IL-6, IL-1β), and SIRT1, Nrf2 and HO-1 mRNA and protein expression were detected.Results:The lung tissue of the CLP group mice was severely damaged, the alveolar interval was widened and a large number of inflammatory cells infiltrated, and there was visible pulmonary capillary hyperemia. The Smith score, the levels of TNF-α, IL-6, IL-1β, MDA and 8-OHdG were significantly increased, the levels of SOD, GSH, SIRT1, Nrf2 and HO-1 were significantly decreased in CLP group. After using SIRT1 specific agonist, the lung injury in CLP+SRT1720 group was significantly alleviated compared with that in CLP group, Smith score and lung tissue TNF-α, IL-6, and IL-1β levels were significantly decreased [Smith score: 2.83±0.75 vs. 5.67±0.52, TNF-α (ng/L): 36.78±5.36 vs. 66.99±5.44, IL-6 (ng/L): 23.97±3.76 vs. 45.70±4.16, IL-1β (ng/L): 16.76±1.39 vs. 39.64±2.59, all P < 0.05], SOD activity and GSH content increased [SOD (kU/g): 115.88±3.31 vs. 101.65±1.09, GSH (μmol/g): 8.42±0.81 vs. 5.74±0.46, both P < 0.05], MDA and 8-OHdG contents decreased [MDA (μmol/g): 5.24±0.33 vs. 9.86±0.66, 8-OHdG (ng/L): 405.76±8.54 vs. 647.12±10.64, both P < 0.05], the mRNA and protein expressions of SIRT1, Nrf2 and HO-1 were increased [SIRT1 mRNA (2 -ΔΔCT): 1.49±0.15 vs. 0.64±0.03, Nrf2 mRNA (2 -ΔΔCT): 1.19±0.08 vs. 0.84±0.02, HO-1 mRNA (2 -ΔΔCT): 1.80±0.41 vs. 0.64±0.11, SIRT1 protein (SIRT1/β-actin): 1.03±0.06 vs. 0.52±0.05, Nrf2 protein (Nrf2/β-actin): 1.14±0.10 vs. 0.63±0.05, HO-1 protein (HO-1/β-actin): 1.01±0.11 vs. 0.73±0.03, all P < 0.05]. The lung injury in CLP+EX527 group was more severe than that in CLP group, Smith score and lung tissue TNF-α, IL-6, IL-1β levels were significantly increased [Smith score: 8.00±0.89 vs. 5.67±0.52, TNF-α (ng/L): 87.15±4.23 vs. 66.99±5.44, IL-6 (ng/L): 66.79±2.93 vs. 45.70±4.16, IL-1β (ng/L): 58.99±2.12 vs. 39.64±2.59, all P < 0.05], SOD activity and GSH content decreased [SOD (kU/g): 72.84±3.85 vs. 101.65±1.09, GSH (μmol/g): 3.30±0.67 vs. 5.74±0.46, both P < 0.05], the contents of MDA and 8-OHdG were increased [MDA (μmol/g): 14.14±0.70 vs. 9.86±0.66, 8-OHdG (ng/L): 927.66±11.47 vs. 647.12±10.64, both P < 0.05], the mRNA and protein expressions of SIRT1, Nrf2 and HO-1 were decreased [SIRT1 mRNA (2 -ΔΔCT): 0.40±0.07 vs. 0.64±0.03, Nrf2 mRNA (2 -ΔΔCT): 0.48±0.07 vs. 0.84±0.02, HO-1 mRNA (2 -ΔΔCT): 0.27±0.14 vs. 0.64±0.11, SIRT1 protein (SIRT1/β-actin): 0.20±0.05 vs. 0.52±0.05, Nrf2 protein (Nrf2/β-actin): 0.45±0.01 vs. 0.63±0.05, HO-1 protein (HO-1/β-actin): 0.36±0.08 vs. 0.73±0.03, all P < 0.05]. Conclusions:In the rat model of ALI induced by sepsis, SIRT1 can regulate the activation of Nrf2/HO-1 signaling pathway, upregulate the expression of downstream antioxidant enzymes, reduce oxidative stress injury, and then alleviate the ALI induced by sepsis in rats.

Objective:To explore the protective effect of sivelestat (SV) against sepsis-induced acute kidney injury (AKI) and its molecular mechanism.Methods:According to the random number table method, 64 male Wistar rats were divided into sham operation group (Sham group), sepsis due to cecal ligation and puncture group (CLP group), low dose of SV treatment group (SL group, 50 mg/kg SV was injected into the tail vein at 12 hours and 24 hours after CLP), and high dose of SV treatment group (SH group, 100 mg/kg SV was injected into the tail vein at 12 hours and 24 hours after CLP), with 16 rats in each group. 48 hours after CLP, the 48-hour survival of rats were recorded, all rats were sacrificed and samples were harvested. Enzyme-linked immunosorbent assay (ELISA) was used to detect the serum levels of kidney injury molecule-1 (KIM-1), interleukins (IL-1β, IL-6), tumor necrosis factor-α (TNF-α) and neutrophil elastase (NE). Hematoxylin-eosin (HE) staining was used to observe histopathological changes and assess renal tubule injury score. Masson staining was used to detect the collagen volume fraction (CVF) of kidney tissue. Western blotting was used to detect the protein expressions of phosphatidylinositol 3-kinase (PI3K), phosphorylation PI3K (p-PI3K), protein kinase B (AKT), phosphorylation AKT (p-AKT), nuclear factor-κB p65 (NF-κB p65) and NE. The protein expressions of p-PI3K, p-AKT, NF-κB p65 were detected by immunohistochemistry.Results:Compared with Sham group, the 48-hour survival rate of CLP group was significantly reduced. Histopathological results showed that large tubular epithelial cells and brush margins were shed, tubular casts were formed, some tubular atrophy, glomerular hyperemia, renal interstitial inflammatory cell infiltration and increased renal tubular injury score. Renal interstitial fibrosis was obvious and CVF increased. The levels of KIM-1, IL-1β, IL-6, TNF-α and NE in serum were significantly elevated in the CLP group. The proteins expression of inflammatory pathway-related p-PI3K/PI3K, p-AKT/AKT, NF-κB p65 and NE were significantly increased in kidney tissue. It suggested that septic rats had renal injury and the PI3K/AKT inflammatory pathway was activated. Compared with CLP group, there was no significant difference in 48-hour survival in SL group and SH group (68.75%, 75.00% vs. 56.25%, both P > 0.05), but kidney injury was significantly relieved. Specifically: renal tubular injury score and CVF significantly decreased [tubular injury score: 2 (1, 2), 1 (1, 1) vs. 2 (2, 3); CVF: (22.36±0.86)%, (18.74±1.05)% vs. (58.38±0.79)%, all P < 0.05]; the serum levels of KIM-1, IL-1β, IL-6, TNF-α and NE also decreased significantly [KIM-1 (ng/L): 145.03±8.88, 117.58±7.02 vs. 158.22±12.00; IL-1β (ng/L): 108.32±9.00, 92.98±8.06 vs. 133.78±8.48; IL-6 (ng/L): 124.33±10.11, 115.42±8.17 vs. 165.19±5.70; TNF-α (ng/L): 321.56±19.29, 289.68±21.57 vs. 424.88±22.76, NE (mol/L): 93.84±9.14, 75.01±10.56 vs. 113.45±6.39, all P < 0.05]; the proteins expression of inflammatory pathway-related p-PI3K/PI3K, p-AKT/AKT, NF-κB p65 and NE were significantly decreased (p-PI3K/PI3K: 0.93±0.06, 0.67±0.04 vs. 1.27±0.08; p-AKT/AKT: 0.78±0.09, 0.47±0.05 vs. 0.96±0.12; NF-κB p65/GAPDH: 1.43±0.13, 0.85±0.08 vs. 1.88±0.17; NE/GAPDH: 1.45±0.06, 0.91±0.04 vs. 1.71±0.08, all P < 0.05), the positive expressions of p-PI3K, p-AKT and NF-κB p65 in kidney tissue were decreased [p-PI3K positive expression area: (13.36±1.84)%, (8.03±1.12)% vs. (21.56±1.20)%; p-AKT positive expression area: (21.57±0.91)%, (15.21±2.76)% vs. (30.81±2.12)%; NF-κB p65 positive expression area: (25.17±1.38)%, (17.07±2.11)% vs. (37.85±2.50)%, all P < 0.05]. Serum inflammatory factor level, and PI3K/AKT pathway related protein, NF-κB p65, NE protein expression level and p-PI3K, p-AKT, NF-κB p65 positive area and other indicators in renal tissue in SH group were further lower than those in SL group (all P < 0.05). Conclusions:SV can ameliorate sepsis-induced AKI. The mechanism may be related to the inhibition of PI3K/AKT pathway, and high dose of SV has better efficacy.

Sepsis-associated acute kidney injury (SA-AKI), as a common renal dysfunction in sepsis, has become one of the major diseases threatening human health with increasing morbidity and mortality. Based on the theory of "gut-kidney axis", the intestine and kidney have a two-way synergistic relationship in sepsis. Intestinal flora imbalance, endogenous metabolite imbalance, and impaired endothelial barrier integrity are involved in renal injury, and the increase of renal inflammatory mediators interferes with the composition of intestinal microorganisms. Therefore, understanding the intestinal-renal crosstalk mechanism of SA-AKI will help to provide a potential basis for new treatment strategies for SA-AKI.

OBJECTIVE: To investigate whether ferroptosis exists in sepsis induced intestinal injury, and to verify the association between ferroptosis in sepsis induced intestinal injury and intestinal inflammation and barrier function by stimulating and inhibiting the nuclear factor E2-related factor 2/glutathione peroxidase 4 (Nrf2/GPX4) pathway. METHODS: Forty-eight SPF grade male Sprague-Darvley (SD) rats with a body weight of 220-250 g were divided into sham operation group (Sham group), sepsis group (CLP group), sepsis+iron chelating agent deferoxamine (DFO) group (CLP+DFO group) and sepsis+ferroptosis inducer Erastin group (CLP+Erastin group) using a random number table method, with 12 rats in each group. The sepsis model was established by cecal ligation and puncture (CLP). The Sham group was only performed with abdominal opening and closing operations. After modeling, the CLP+DFO group received subcutaneous injection of 20 mg/kg of DFO, the CLP+Erastin group was intraperitoneally injected with 20 mg/kg of Erastin. Each group received subcutaneous injection of 50 mg/kg physiological saline for fluid resuscitation after surgery, and the survival status of the rats was observed 24 hours after surgery. At 24 hours after model establishment, 6 rats in each group were selected. First, live small intestine tissue was taken for observation of mitochondrial morphology in smooth muscle cells under transmission electron microscopy and determination of reactive oxygen species (ROS). Then, blood was collected from the abdominal aorta and euthanized. The remaining 6 rats were sacrificed after completing blood collection from the abdominal aorta, and then small intestine tissue was taken. Western blotting was used to detect the expression of intestinal injury markers such as Claudin-1 and ferroptosis related proteins GPX4 and Nrf2. Observe the pathological changes of small intestine tissue using hematoxylin-eosin (HE) staining and complete Chiu score; Detection of tumor necrosis factor-α (TNF-α), interleukins (IL-1β, IL-6) levels in serum using enzyme-linked immunosorbent assay (ELISA). The levels of serum iron ions (Fe³⁺), malondialdehyde (MDA), and D-lactate dehydrogenase (D-LDH) were measured. RESULTS: (1) Compared with the Sham group, the 24-hour survival rate of rats in the CLP group and CLP+Erastin group significantly decreased (66.7%, 50.0% vs. 100%, both P < 0.05), while there was no significant difference in the CLP+DFO group (83.3% vs. 100%, P = 0.25). (2) Western blotting results showed that compared with the Sham group, the expressions of GPX4 and Claudin-1 in the small intestine tissue of the CLP group, CLP+DFO group, and CLP+Erastin group decreased significantly, while the expression of Nrf2 increased significantly (GPX4/β-actin: 0.56±0.02, 1.03±0.01, 0.32±0.01 vs. 1.57±0.01, Claudin-1/β-actin: 0.60±0.04, 0.96±0.07, 0.41±0.01 vs. 1.40±0.01, Nrf2/β-actin: 0.88±0.02, 0.72±0.01, 1.14±0.01 vs. 0.43±0.02, all P < 0.05). Compared with the CLP group, the expressions of GPX4 and Claudin-1 were significantly increased in the CLP+DFO group, while the expression of Nrf2 was significantly reduced. In the CLP+Erastin group, the expressions of GPX4 and Claudin-1 further decreased, while the expression of Nrf2 further increased (all P < 0.05). (3) Under the light microscope, compared with the Sham group, the CLP group, CLP+DFO group, and CLP+Erastin group showed structural disorder in the small intestinal mucosa and submucosal tissue, significant infiltration of inflammatory cells, and destruction of glandular and villous structures. The Chui score was significantly higher (3.25±0.46, 2.00±0.82, 4.50±0.55 vs. 1.25±0.45, all P < 0.05). (4) Under transmission electron microscopy, compared with the Sham group, the mitochondria in the other three groups of small intestinal smooth muscle cells showed varying degrees of volume reduction, increased membrane density, and reduced or disappeared cristae. The CLP+Erastin group showed the most significant changes, while the CLP+DFO group showed only slight changes in mitochondrial morphology. (5) Compared to the Sham group, the CLP group, CLP+DFO group, and CLP+Erastin group had serum levels of TNF-α, IL-1β, IL-6, MDA, D-LDH, and ROS in small intestine tissue were significantly increased, while the serum Fe³⁺ content was significantly reduced [TNF-α (ng/L): 21.49±1.41, 17.24±1.00, 28.66±2.72 vs. 14.17±1.24; IL-1β (ng/L): 108.40±3.09, 43.19±8.75, 145.70±11.00 vs. 24.50±5.55; IL-6 (ng/L): 112.50±9.76, 45.90±6.52, 151.80±9.38 vs. 12.89±6.11; MDA (μmol/L): 5.61±0.49, 3.89±0.28, 8.56±1.17 vs. 1.86±0.41; D-LDH (kU/L): 39.39±3.22, 25.38±2.34, 53.29±10.53 vs. 10.79±0.52; ROS (fluorescence intensity): 90 712±6 436, 73 278±4 775, 110 913±9 287 vs. 54 318±2 226; Fe³⁺ (μmol/L): 22.19±1.34, 34.05±1.94, 12.99±1.08 vs. 51.74±11.07; all P < 0.05]. Compared with CLP group, the levels of TNF-α, IL-1β, IL-6, MDA, D-LDH and ROS in CLP+Erastin group were further increased, and the content of Fe³⁺ was further decreased, the CLP+DFO group was the opposite (all P < 0.05). CONCLUSIONS Ferroptosis exists in the intestinal injury of septic rats, and stimulating or inhibiting ferroptosis through the Nrf2/GPX4 pathway can effectively intervene in the inflammatory state and intestinal mechanical barrier of the body.
Rats ; Male ; Animals ; NF-E2-Related Factor 2 ; Tumor Necrosis Factor-alpha ; Ferroptosis ; Reactive Oxygen Species ; Actins ; Claudin-1 ; Interleukin-6 ; Sepsis/metabolism* ; Iron