Data driven analysis reveals prognostic genes and immunological targets in human sepsis-associated acute kidney injury

BACKGROUND:The molecular mechanism of sepsis-associated acute kidney injury(SA-AKI)is unclear.We analyzed co-differentially expressed genes(co-DEGs)to elucidate the underlying mechanism and intervention targets of SA-AKI.METHODS:The microarray datasets GSE65682,GSE30718,and GSE174220 were downloaded from the Gene Expression Omnibus(GEO)database.We identified the co-DEGs and constructed a gene co-expression network to screen the hub genes.We analyzed immune correlations and disease correlations and performed functional annotation of the hub genes.We also performed single-cell and microenvironment analyses and investigated the enrichment pathways and the main transcription factors.Finally,we conducted a correlation analysis to evaluate the role of the hub genes.RESULTS:Interleukin 32(IL32)was identified as the hub gene in SA-AKI,and the main enriched signaling pathways were associated with hemopoiesis,cellular response to cytokine stimulus,inflammatory response,and regulation of kidney development.Additionally,IL32 was significantly associated with mortality in SA-AKI patients.Monocytes,macrophages,T cells,and NK cells were closely related to IL32 and were involved in the immune microenvironment in SA-AKI patients.IL32 expression increased significantly in the kidney of septic mouse.Toll-like receptor 2(TLR2)was significantly and negatively correlated with IL32.CONCLUSION:IL32 is the key gene involved in SA-AKI and is significantly associated with prognosis.TLR2 and relevant immune cells are closely related to key genes.

Study of the OPG/RANKL/RANK signaling pathway in mice treated with sepsis-related acute kidney injury

Objective:The objective of this study was to investigate the alterations and potential implications of the Osteoprotegerin(OPG)/Receptor Activator of Nuclear Factor-kappa B Ligand(RANKL)/Receptor Activator of Nuclear Factor-kappa B(RANK)signaling pathway factors in a murine model of sepsis-associated acute kidney injury(SA-AKI).This research aimed to offer novel insights into the mechanistic exploration of SA-AKI.Methods:The SA-AKI model group(CLP group)was established through cecal ligation and puncture surgery(CLP),while the control group consisted of sham-operated animals(Sham group)subjected only to laparotomy without cecal ligation and puncture.Blood samples were collected 24 h post-surgery,and murine kidney tissues were harvested upon euthanasia.Serum levels of Serum Creatinine(Scr)and Blood Urea Nitrogen(BUN)were quantified using assay kits.Furthermore,serum levels of interleukin-6(IL-6),tumor necrosis factor-alpha(TNF-α),and interleukin-1 beta(IL-1β)were assessed through enzyme-linked immunosorbent assay(ELISA).Renal tissue pathological alterations were examined employing hematoxylin-eosin staining(HE),and the mRNA and protein levels of OPG,RANKL,and RANK in murine kidney tissues were determined via reverse transcription-quantitative polymerase chain reaction(RT-qPCR)and Western blotting.Results:Comparative analysis revealed that,in comparison to the Sham group,the CLP group demonstrated a significant elevation in the levels of Scr,BUN,IL-6,TNF-α,and IL-1β,with statistically significant disparities(all P<0.05).Histopathological examination of the CLP group's kidneys unveiled glomerular congestion,edema,partial ischemic wrinkling,enlargement of interstitial spaces,the presence of necrotic epithelial cells in select renal tubules,tubular luminal dilation,varying degrees of interstitial edema,and infiltration by a limited number of inflammatory cells.In parallel,relative to the Sham group,the CLP group exhibited substantial upregulation in mRNA expression of OPG and RANK in renal tissues,while RANKL mRNA expression experienced marked downregulation,with statistically significant distinctions(all P<0.05).Moreover,in comparison with the Sham group,the CLP group demonstrated an elevation in protein expression of OPG and RANK in kidney tissues,whereas RANKL protein expression displayed significant downregulation,with statistically significant differences(all P<0.05).Conclusion:In a murine sepsis model,augmented expression of OPG and RANK,coupled with diminished RANKL expression,suggests the potential involvement of the OPG/RANKL/RANK signaling pathway in the pathophysiological progression of SA-AKI.

Timing of Continuous Renal Replacement Therapy Initiation in Sepsis-Associated Acute Kidney Injury: A Comprehensive Review and Future Directions

This review examines the application of continuous renal replacement therapy(CRRT)in patients with sepsis-associated acute kidney injury(S-AKI),with a particular focus on the timing of CRRT initiation.This review addresses the controversy surrounding initiation timing and proposes future research directions.Through a systematic review of recent literature on CRRT for S-AKI,working principles,therapeutic mechanisms,initiation timing of CRRT,and related meta-analyses were summarized.Current studies indicate that the optimal timing for CRRT initiation in S-AKI patients remains inconclusive,with ongoing debate regarding whether early initiation significantly improves patient survival and renal function.This lack of consensus reflects the heterogeneity of the S-AKI patient population and the limitations of existing research methodologies.Future studies should focus on advancing the application of precision medicine in S-AKI and developing individualized treatment strategies by integrating multidimensional information to optimize CRRT utilization and improve patient outcomes.

Value of early diagnosis of sepsis complicated with acute kidney injury by renal contrast-enhanced ultrasound

BACKGROUND The incidence of acute kidney injury(AKI)in patients with sepsis is high,and the prognosis of patients with septic AKI is poor.The early diagnosis and treatment of septic AKI is of great significance in improving the prognosis of patients with sepsis.AIM To explore the value of contrast-enhanced ultrasound(CEUS),serum creatinine(Scr),and other indicators in the early diagnosis of septic AKI.METHODS Ninety patients with sepsis during hospitalization at Tongji Hospital of Tongji University were recruited as subjects.Each patient was recorded with relevant basic data,clinical indicators,and CEUS results.The patients were divided into AKI group and non-AKI group according to the results of renal function diagnosis after 48 h.On the 7th day,the renal function of the non-AKI group was re-evaluated and the patients were further divided into AKI subgroup and non-AKI subgroup.The differences of the indicators in different groups were compared,and the diagnostic value of each indicator and their combination for septic AKI was analyzed.RESULTS Systemic inflammatory response score(2.58±0.75),blood lactic acid(3.01±1.33 mmol/L),Scr(141.82±27.19μmol/L),blood urea nitrogen(4.41±0.81mmol/L),and rise time(10.23±2.63 s)in the AKI group were higher than those in the non-AKI group.Peak intensity(PI)(10.78±3.98 dB)and wash in slope(WIS)(1.07±0.53 dB/s)were lower than those in the non-AKI group.The differences were statistically significant(P<0.05).The PI(12.83±3.77 dB)and WIS(1.22±0.68 dB/s)in the AKI subgroup were lower than those in the non-AKI subgroup,and the differences were statistically significant(P<0.05).The area under curve(AUC)of Scr for the diagnosis of septic AKI was 0.825 with a sensitivity of 56.76% and a specificity of 100%.The AUCs of WIS and PI(0.928 and 0.912)were higher than those of Scr.Their sensitivities were 100%,but the specificities were 71.70% and 75.47%.The AUC of the combination of three indicators for the diagnosis of septic AKI was 0.943,which was significantly higher than the AUC diagnosed by each single indicator.The sensitivity was 94.59%,and the specificity was 81.13%.CONCLUSION The combination of Scr,PI,and WIS can improve the diagnostic accuracy of septic AKI.PI and WIS are expected to predict the occurrence of early septic AKI.

Influence of thymopentin-5 on renal pathology and relevant indexes of serum in rats with acute kidney injury caused by sepsis

Objective:To discuss thymopentin-5 on renal pathology and relevant indexes of serum with sepsis-caused acute kidney injury(AKI)caused by cecal ligation and puncture(CLP).Methods:90 cases of healthy and male SD rats were randomly divided into 3 groups:control group(C group),sepsis group(S group),thymopentin group(T group).These groups were divided into five time point including 1 h,6 h,12 h,24 h and 48 h with 6 rats in each time point.The sepsis model was made by CLP.The blood and kidney tissue were collected in each time point.Changes of renal pathology were observed under light microscope and relevant indexes like serum creatinin(Cr),blood urea nitrogen(Bun),tumor necrosis factorα(TNF-α),interleukin-10(IL-10),CD4+/CD8+were tested and analyzed.Results:In T group,concentrations of Cr,Bun in 6 h after CLP started to rise,reached peak in 24 h and decreased in 48 h,which were all lower than S group(p<.05)and higher than C group(p<.05).Compared with C group,concentrations of TNF-αin 1 h significantly improved,reached peak in 12 h and decreased in 24 h,which were all lower than S group(p<.05);and concentrations of IL-10 in 1 h significantly decreased,reached peak in 12 h and rised in 24 h,which were all more than S group(p<.05).In T group,CD4+/CD8+ratio in 6 h after CLP started to decrease,reached the lowest in 24 h and rised in 48 h,which were all lower than S group(p<.05)and significantly lower than C group(p<.05).Conclusions:Thymopentin-5 plays the role of renal protection in AKI caused by sepsis.

A pulmonary source of infection in patients with sepsis-associated acute kidney injury leads to a worse outcome and poor recovery of kidney function

BACKGROUND:Hospital mortality rates are higher among patients with sepsis-associated acute kidney injury(SA-AKI)than among patients with sepsis.However,the pathogenesis underlying SA-AKI remains unclear.We hypothesized that the source of infection affects development of SA-AKI.We aim to explore the relationship between the anatomical source of infection and outcome in patients with SA-AKI.METHODS:Between January 2013 and January 2018,113 patients with SA-AKI admitted to our Emergency Center were identifi ed and divided into two groups:those with pulmonary infections and those with other sources of infection.For each patient,we collected data from admission until either discharge or death.We also recorded the clinical outcome after 90 days for the discharged patients.RESULTS:The most common source of infection was the lung(52/113 cases,46%),followed by gastrointestinal(GI)(25/113 cases,22.1%)and urinary(22/113,19.5%)sources.Our analysis showed that patients with SA-AKI had a significantly worse outcome(30/52 cases,P<0.001)and poorer kidney recovery(P=0.015)with pulmonary sources of infection than those infected by another source.Data also showed that patients not infected by a pulmonary source more likely experienced shock(28/61 cases,P=0.037).CONCLUSION:This study demonstrated that the source of infection infl uenced the outcome of SA-AKI patients in an independent manner.Lung injury may influence renal function in an asyet undetermined manner as the recovery of kidney function was poorer in SA-AKI patients with a pulmonary source of infection.

Eff ects of continuous renal replacement therapy on infl ammation-related anemia, iron metabolism and prognosis in sepsis patients with acute kidney injury

BACKGROUND:This study aims to evaluate the eff ect of continuous renal replacement therapy(CRRT)on inflammation-related anemia,iron metabolism,and the prognosis in sepsis patients with acute kidney injury(AKI).METHODS:Sepsis patients with AKI were prospectively enrolled and randomized into the CRRT and control groups.The clinical and laboratory data on days 1,3 and 7 after intensive care unit(ICU)admission were collected.The serum interleukin(IL)-6,hepcidin,erythropoietin,ferritin,and soluble transferrin receptor(sTfR)were determined by enzyme-linked immunosorbent assay.The Sequential Organ Failure Assessment(SOFA)score and 28-day mortality were recorded.Data were analyzed using Pearson’s Chi-square test or Fisher’s exact test(categorical variables),and Mann-Whitney U-test or t-test(continuous variables).RESULTS:The hemoglobin and serum erythropoietin levels did not signifi cantly diff er between the CRRT and control groups though gradually decreased within the first week of ICU admission.On days 3 and 7,the serum IL-6,hepcidin,ferritin,and red blood cell distribution width significantly decreased in the CRRT group compared to the control group(all P<0.05).On day 7,the serum iron was significantly elevated in the CRRT group compared to the control group(P<0.05).However,the serum sTfR did not signifi cantly diff er between the groups over time.In addition,the SOFA scores were signifi cantly lower in the CRRT group compared to the control group on day 7.The 28-day mortality did not signifi cantly diff er between the control and CRRT groups(38.0%vs.28.2%,P=0.332).CONCLUSION:CRRT might have beneficial effects on the improvement in inflammationrelated iron metabolism and disease severity during the fi rst week of ICU admission but not anemia and 28-day mortality in sepsis patients with AKI.

Ticagrelor Protects against Sepsis-Induced Acute Kidney Injury through an Adenosine Receptor-Dependent Pathway

Objective Ticagrelor is a widely used anti-platelet drug.However,the mechanisms by which ticagrelor protects against sepsis-induced acute kidney injury(AKI)have not been clearly demonstrated.We designed this study to explore the protective effect of ticagrelor on sepsis-induced AKI and to explore the underlying mechanisms.Methods C57BL6J mice received oral ticagrelor(20 mg/kg and 50 mg/kg)for 7 days,and then caecal ligation and puncture(CLP)were performed.An adenosine receptor antagonist,CGS15943,was administered(10 mg/kg,intraperitoneal injection)to block the adenosine pathway 2 h before CLP.After 24 h,serum creatinine levels were measured.Periodic acid-Schiff(PAS)staining and terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling(TUNEL)staining were employed to analyze pathological changes and cell apoptosis.Serum concentrations of tumor necrosis factor-α(TNF-α),interleukin-1β(IL-1β),and mRNA expression of tissue TNF-αand IL-1βwere detected.Western blotting analysis was used to determine AKT and mammalian target of rapamycin(mTOR)protein expression in the kidney.Results PAS staining showed less swelling of renal tubules,and TUNEL staining revealed less cell apoptosis in the ticagrelor group than in the CLP group.Serum creatinine levels were significantly lower in the ticagrelor group than in the CLP group.Moreover,significantly lower serum and kidney levels of TNF-αand IL-1βwere observed in the ticagrelor group.CGS15943 blocked the effects of ticagrelor.Western blotting analysis showed increased phosphorylation of AKT and mTOR in the kidneys of the 50 mg/kg ticagrelor group.The adenosine receptor antagonist inhibited the activation of AKT and mTOR.Conclusion This study demonstrates that the protective effect of ticagrelor on sepsis-induced AKI depends on adenosine receptor activation and the subsequent increase of AKT and mTOR phosphorylation.

Efficacy of Ulinastatin Combined with Continuous Renal Replacement Therapy in the Treatment of Sepsis Acute Kidney Injury and Its Effects on Systemic Inflammation, Immune Function and miRAN Expression

Objective: To research the effectiveness of ulinastatin in combination with continuous renal replacement therapy in treating sepsis acute kidney injury and its effect on systemic inflammation, immune function and miRAN expression. Methods: The 84 patients who were diagnosed with sepsis complicated by acute kidney injury in our hospital between May 2020 and June 2022 were chosen and randomly assigned to the study group (n = 42) and the control group (n = 42). Ulinastatin in combination with continuous renal replacement therapy was administered to the study group, whereas the control group was administered with continuous renal replacement therapy alone. Both groups’ clinical effects were observed. The levels of blood urea nitrogen (BUN), serum creatinine (SCr), tumor necrosis factor-α (TNF-α), high sensitivity Creactive protein (hs-CRP), vascular cell adhesion molecule-1 (VCAM-1), IgG, IgA, IgM, expression levels of miR-233 and miR-10a were compared among both the groups, pre-, and post-treatment. Results: The study group’s overall effectiveness rate was higher that is 95.24%, in comparison to the control group’s 78.57%, and this difference was statistically significant (P α, hs-CRP, VCAM-1, and miR-233 and miR-10a expression levels in both the study and control groups were decreased, however, the study group had reduced levels in comparison to the control group, with statistically significant differences (P P Conclusion: Ulinastatin in combination with continuous renal replacement therapy for treating sepsis acute kidney injury exhibits a positive effect and can significantly improve the systemic inflammation and immune function in patients.

Neutrophil-to-lymphocyte ratio predicts acute kidney injury occurrence after gastrointestinal and hepatobiliary surgery

BACKGROUND Postoperative acute kidney injury(AKI) is a complex pathological process involved intrarenal and systemic inflammation caused by renal hypoperfusion, nephrotoxic drugs and urinary obstruction. Neutrophil-to-lymphocyte ratio(NLR) is a marker of inflammation reflecting the progress of many diseases. However, whether NLR at admission can predict the occurrence of AKI after surgery in the intensive care unit(ICU) remains unknown.AIM To clarify the relationship between NLR and the occurrence of AKI in patients with gastrointestinal and hepatobiliary surgery in the ICU.METHODS A retrospective analysis of 282 patients receiving surgical ICU care after gastrointestinal and hepatobiliary surgery in our hospital from December 2014 to December 2018 was performed.RESULTS Postoperative AKI occurred in 84 patients(29.79%) in this cohort. NLR by the multivariate analysis was an independent risk factor for occurrence of postoperative AKI in patients with gastrointestinal and hepatobiliary surgery in the ICU. In this cohort, receiver operating characteristic curves of AKI occurrence showed that the optimal cut-off value of NLR was 8.380. NLR was found to be significantly correlated with the white blood cell count, neutrophil count, lymphocyte count, arterial lactate and dialysis(P < 0.05). Additionally, NLR value at admission was higher in AKI patients compared with the non-AKI patients and increased with the severity of AKI. Patients with NLR ≥ 8.380 exhibited significantly higher incidences of postoperative AKI and severe AKI than patients with NLR < 8.380(AKI: 38.12% vs 14.85%, P < 0.001;severe AKI: 14.36% vs 1.98%, P = 0.001).CONCLUSION NLR at admission is a predictor of AKI occurrence in patients with gastrointestinal and hepatobiliary surgery in ICU. NLR should be included in the routine assessment of AKI occurrence.

Serum bicarbonate may independently predict acute kidney injury in critically ill patients:An observational study

AIM: To explore whether serum bicarbonate at admission to intensive care unit(ICU) predicted development of acute kidney injury(AKI).METHODS:We studied all patients admitted to our ICU over a 2 year period(February 2010 to 2012).The ICU has a case mix of medical and surgical patients excluding cardiac surgical,trauma and neurosurgical patients.We analysed 2035 consecutive patients admitted to ICU during the study period.Data were collected by two investigators independently and in duplicate using a standardised spread sheet to ensure accuracy.Ambiguous data were checked for accuracy where indicated.AKI was defined using the Kidney Disease Improving Global Outcomes criteria.Patients were divided into two groups;patients who developed AKI or those who did not,in order to compare the baseline characteristics,and laboratory and physiologic data of the two cohorts.Regression analysis was used to identify if serum bicarbonate on admission predicted the development of AKI.RESULTS:Of 2036 patients 152(7.5%)were excluded due to missing data.AKI developed in 43.1%of the patients.The AKI group,compared to the nonAKI group,was sicker based on their lower systolic,diastolic and mean arterial pressures and a higher acutephysiology and chronic health evaluation(APACHE)Ⅲand SAPSⅡscores.Moreover,patients who developed AKI had more co-morbidities and a higher proportion of patients who developed AKI required mechanical ventilation.The multi-regression analysis of independent variables showed that serum bicarbonate on admission(OR=0.821;95%CI:0.796-0.846;P<0.0001),APACHEⅢ(OR=1.011;95%CI:1.007-1.015;P<0.0001),age(OR=1.016;95%CI:1.008-1.024;P<0.0001)and presence of sepsis at ICU admission(OR=2.819;95%CI:2.122-23.744;P=0.004)were each significant independent predictors of AKI.The area under the ROC curve was 0.8(95%CI:0.78-0.83),thereby demonstrating that the predictive model has relatively good discriminating power for predicting AKI.CONCLUSION:Serum bicarbonate on admission may independently be used to make a diagnosis of AKI.

Changing picture of renal cortical necrosis in acute kidney injury in developing country

Renal cortical necrosis(RCN) is characterized by patchy or diffuse ischemic destruction of all the elements of renal cortex resulting from significantly diminished renal arterial perfusion due to vascular spasm and microvascular injury. In addition, direct endothelial injury particularly in setting of sepsis, eclampsia, haemolytic uremic syndrome(HUS) and snake bite may lead to endovascular thrombosis with subsequent renal ischemia. Progression to end stage renal disease is a rule in diffuse cortical necrosis. It is a rare cause of acute kidney injury(AKI) in developed countries with frequency of 1.9%-2% of all patients with AKI. In contrast, RCN incidence is higher in developing countries ranging between 6%-7% of all causes of AKI. Obstetric complications(septic abortion, puerperal sepsis, abruptio placentae, postpartum haemorrhage and eclampsia) are the main(60%-70%) causes of RCN in developing countries. The remaining 30%-40% cases of RCN are caused by non-obstetrical causes, mostly due to sepsis and HUS. The incidence of RCN ranges from 10% to 30% of all cases of obstetric AKI compared with only 5% in non-gravid patients. In the developed countries, RCN accounts for 2% of all cases of AKI in adults and more than 20% of AKI during the third trimester of pregnancy. The reported incidence of RCN in obstetrical AKI varies between 18%-42.8% in different Indian studies. However, the overall incidence of RCN in pregnancy related AKI has decreased from 20%-30% to 5% in the past two decades in India. Currently RCN accounts for 3% of all causes of AKI. The incidence of RCN in obstetrical AKI was 1.44% in our recent study. HUS is most common cause of RCN in non-obstetrical group, while puerperal sepsis is leading cause of RCN in obstetric group. Because of the catastrophic sequelae of RCN, its prevention and aggressive management should always be important for the better renal outcome and prognosis of the patients.

Acute kidney injury classification: AKIN and RIFLE criteria in critical patients

Acute kidney injury(AKI) is a common and serious complication in critically ill patients. The mortality rate remains high despite improved renal replacement techniques. A possible cause of the high mortality rate is that intensive care unit patients tend to be older and more debilitated than before. Pathophysiological factors associated with AKI are also implicated in the failure of other organs, indicating that AKI is often part of a multiple organ failure syndrome. Until recently, there was a lack of consensus as to the best definition, characterization, and evaluation of acute renal failure. This lack of a standard definition has been a major impediment to progress in clinical and basic research. The introduction of the risk, injury, failure, loss, and end-stage kidney disease criteria and the modified version proposed by the Acute Kidney Injury Network have increased the conceptual understanding of AKI syndrome, and these criteria have been successfully tested in clinical studies. This article reviews current findings concerning the application of these criteria for assessing epidemiology and predicting outcome in specific homogeneous critically ill patient groups.

MicroRNA-30a inhibits cell proliferation in a sepsis-induced acute kidney injury model by targeting the YAP-TEAD complex

Background Acute kidney injury(AKI)is a primary feature of renal complications in patients with sepsis.MicroRNA(miRNA/miR)-30a is an essential regulator of cardiovascular diseases,tumors,phagocytosis,and other physical processes,but whether it participates in sepsis-induced AKI(sepsis-AKI)is unknown.We aimed to elucidate the functions and molecular mechanism underlying miR-30a activity in sepsis-AKI.Methods The classical cecal ligation and puncture(CLP)method and lipopolysaccharide(LPS)-induced Human Kidney 2(HK-2)cells were used to establish in vivo and in vitro sepsis-AKI models.Specific pathogen-free and mature male Sprague-Dawley(SD)rats,aged 6–8 weeks(weight 200–250 g),were randomly divided into five-time phase subgroups.Fluid resuscitation with 30 mL/kg 37°C saline was administered after the operation,without antibiotics.Formalin-fixed,paraffin-embedded kidney sections were stained with hematoxylin and eosin.SD rat kidney tissue samples were collected for analysis by real-time quantitative polymerase chain reaction and enzyme-linked immunosorbent assay.HK-2 cells were transfected with hsa-miR-30a-3p mimics or inhibitors,and compared with untreated normal controls.RNA,protein,and cell viability were evaluated by quantitative reverse transcription-polymerase chain reaction(qRT-PCR),western blot,and cell counting kit-8 methods.A Dual-Luciferase Assay Kit(Promega)was used to measure luciferase activity 48 h after transfection with miR-30a-3p mimics.Results Expression levels of miR-30a-3p and miR-30a-5p in renal tissues of the sepsis group were significantly reduced at 12 h and 24 h(P<0.05).Tumor necrosis factor-α(TNF-α)and interleukin-1β(IL-1β)were significantly increased in renal tissue 3 h after the operation in rats(P<0.05),and gradually decreased 6 h,12 h,and 24 h after CLP.Levels of miR-30a-5p and miR-30a-3p were significantly down-regulated at 3 h after LPS treatment(P<0.05),and gradually decreased in HK-2 cells.One hour after LPS(10µg/mL)treatment,TNF-αand IL-1βlevels in HK-2 cells were significantly up-regulated(P<0.05),and they were markedly down-regulated after 3 h(P<0.05).IL-6 expression levels began to rise after LPS treatment of cells,peaked at 6 h(P<0.05),and then decreased to the initial level within a few hours.Stimulation with 10µg/mL LPS promoted HK-2 cells proliferation,which was inhibited after miR-30a-3p-mimic transfection.Bioinformatics prediction identified 37 potential miR-30a-3p target genes,including transcriptional enhanced associate domain 1(TEAD1).After transfection of HK-2 cells with miR-30a-3p mimics and miR-30a-3p inhibitor,TEAD1 transcript was significantly up-and down-regulated,respectively(both P<0.05).After LPS treatment(24 h),expression of TEAD1 in the inhibitors group was significantly increased(P<0.01),while that in the mimics group was significantly suppressed(P<0.01).In the dual luciferase reporter experiment,miR-30a-3p overexpression decreased fluorescence intensity(P<0.01)from TEAD1-wt-containing plasmids,but did not influence fluorescence intensity from TEAD1-muta-containing plasmids.LPS may promote HK-2 cells proliferation through the miR-30a-3p/TEAD1 pathway.Conclusion In a background of expression of inflammatory factors,including TNF-α,IL-1β,and IL-6,which were transiently increased in the sepsis-AKI model,miR-30a was down-regulated.Down-regulated miR-30a-3p may promote cell proliferation by targeting TEAD1 in LPS-induced HK-2 cells,demonstrating its potential as a biomarker for early sepsis-AKI diagnosis.

Effect of Platelet-derived P-selectin on Neutrophil Recruitment in a Mouse Model of Sepsis-induced Acute Kidney Injury

Background：Acute kidney injury （AKI） is a severe disease in critically ill patients.Neutrophil infiltration into kidney was associated with the development of AKI,and P-selectin may be involved in the process of neutrophil recruitment in kidney.This study aimed to explore the potential effect of platelet-derived P-selectin on neutrophil recruitment in a mouse model of sepsis-induced AKI.Methods：A total of 30 C57BL/6 male mice were divided into five groups （n =6 in each）：sham group,sepsis group,anti-Ly6G group,anti-P-selectin group,and platelet depletion group.Sepsis was induced by cecal ligation and puncture.Serum creatinine concentration and platelet activity were measured by biochemical detector and flow cytometry,respectively.Histological and pathological features were analyzed using hematoxylin-eosin （HE） and immunohistochemi stry （IHC） staining,respectively.Myeloperoxidase （M PO） activity was detected with MPO assay.Unpaired t-test was used for data analysis.Results：Serum creatinine increased significantly in septic group compared to sham group （2.68 ± 0.27 mg/dl vs.0.82 ± 0.19 mg/dl,t =12.06,P =0.0000） but attenuated in antibodies-treated animals compared to septic group （anti-Ly6G：1.62 ± 0.30 mg/dl vs.2.68 ± 0.27 mg/dl,t =5.76,P=0.0004;anti-P-selectin：1.76 ± 0.31 mg/dl vs.2.68 ± 0.27 mg/dl,t =4.92,P =0.0012;and platelet depletion：1.93 ± 0.29 mg/dl vs.2.68 ± 0.27 mg/dl,t =4.14,P =0.0032）.Platelet amount significantly decreased compared to sham group （658.20 ± 60.64 × 109/L vs.822.00 ± 48.60 × 109/L,t =4.71,P =0.0015） in septic mice,especially in platelet depletion group （240.80 ± 44.98 × 109/L vs.822.00 ± 48.60 × 109/L,t =19.63,P =0.0000）.P-selectin activity was significantly increased in septic group compared to sham group （16.54 ± 1.60% vs.1.90 ± 0.29%,t =15.64,P =0.0000） but decreased significantly in platelet depletion group compared to septic group （3.62 ± 0.68% vs.16.54 ± 1.60%,t =12.89,P =0.0002）.IHC analysis shown that neutrophil infiltration increased in septic mice compared to sham group （36.67 ± 3.79% vs.9.17 ± 1.61%,t =11.58,P =0.0003） and function-blocked groups （anti-Ly6G：36.67 ± 3.79% vs.15.33 ± 1.53%,t =9.05,P 0.0008;anti-P-selectin：36.67 ± 3.79% vs.21.33 ± 1.53%,t =6.51,P=0.0029;and platelet depletion：36.67 ± 3.79% vs.23.33 ± 3.06%,t =4.75,P =0.0090）.MPO increased significantly in septic group compared to control （49.73 ± 1.83 ng/mg prot vs.13.04 ± 2.16 ng/mg prot,t =19.03,P =0.0000） but decreased in function-blocked groups compared to septic group （anti-Ly6G：26.52 ± 3.86 ng/mg prot vs.49.73 ± 1.83 ng/mg prot,t =9.59,P =0.0000;anti-P-selectin：33.06 ± 6.75 ng/mg prot vs.49.73 ± 1.83 ng/mg prot,t =4.85,P =0.0013;and platelet depletion：33.37 ± 2.25 ng/mg prot vs.49.73 ± 1.83 ng/mg prot,t =5.33,P =0.0007）.Conclusion：Platelets-derived P-selectin may be involved in the development of septic AKI through inducing neutrophil infiltration into kidney.

Expression and correlation of pyruvate kinase M2 and miRNA‑122 in sepsis associated AKI

Objective:To investigate the expression and correlation of pyruvate kinase M2 and miRNA-122 in sepsis associated acute kidney injury(S-AKI).Methods:A mouse model of S-AKI was induced by cecal ligation and perforation(CLP),and normal mice were used in the control group.Serum and renal tissue were collected from each group,respectively,and the levels of blood urea nitrogen(BUN)and creatinine(Cr)were detected by biochemical analyzer.The levels of lactate in serum and kidney tissue of mice in each group were detected by colorimetric method.Real-time quantitative PCR(RT-qPCR)was used to detect the expression of miRNA-122 and pkm2 mRNA in kidney tissue in each group.Western blotting was used to detect the expression of PKM2 protein in kidney tissue in each group.Pearson's method was used to analyze the pairwise correlation of miRNA-122,PKM2 and lactate levels.Results:(1)Compared with the control group,the levels of BUN and Cr increased significantly after 12 h and 24 h of CLP treatment(P<0.05).(2)Compared with the control group,after 12 h and 24 h of CLP treatment,the levels of lactate in the serum and kidney tissue of the mice were significantly higher than those in the control group(P<0.05).(3)Compared with the control group,the expression of miRNA-122 in renal tissue began to decrease at 4 h after CLP,and decreased significantly at 12-24 h(P<0.05).Compared with the control group,the expression of pKm2 mRNA and protein in renal tissue began to increase after 4 h of CLP,and increased significantly at 12-24 h(P<0.05).(4)Correlation analysis showed that miRNA-122 was significantly negatively correlated with lactate level(P<0.0001,r=-0.7167).There was a significant positive correlation between pkm2 mRNA and lactate level(P<0.0001,r=0.6817).There was a significant negative correlation between miRNA-122 and pkm2 mRNA expression(P<0.0001,r=-0.8122).Conclusion:In S-AKI,dysregulated expression of miRNA-122 may aggravate the occurrence and development of AKI by regulating the level of PKM2,and promoting aerobic glycolysis and lactate levels.

Epidemiology of acute kidney injury in intensive care septic patients based on the KDIGO guidelines

Background Acute kidney injury （AKI） is a common complication of sepsis,which is associated with higher risks of adverse outcomes.Recently,kidney disease：improving global outcomes （KDIGO） recommended a new guideline forAKI,including a little modification on the AKI staging criteria.Methods This retrospective study included 211 septic patients admitted to the intensive care unit （ICU） at Xiangya Hospital,Central South University from January 2008 to January 2011.AKI was diagnosed and classified according to the KDIGO or acute kidney injury network （AKIN） criteria.Differences between the AKI and non-AKI groups for baseline characteristics,laboratory examinations,etiology,outcomes,as well as the risk factors for AKI and 28-day mortality were analyzed.The reliability of the KDIGO criteria was also evaluated by comparing it with the AKIN criteria.Results The overall incidence of AKI in septic patients was 47.9％,and the 28-day mortality was 32.7％.The incidence of AKI was significantly higher in patients with more severe sepsis.Indicators of hepatic and respiratory function were significantly worse in the AKI group.Furthermore,a higher proportion of patients were infected with Enterobacter cloacae in the AKI group.The independent risk factors for AKI were shock,the number of organ failures,blood urea nitrogen （BUN）levels,and the use of vasopressors.The independent risk factors for mortality were BUN and creatine kinase-MB （CK-MB）levels.Both the KDIGO criteria and the AKIN criteria were significantly associated with 28-day mortality.Conclusions The incidence and 28-day mortality of AKI were very high in ICU septic patients.Greater attention should be paid to AKI-induced hepatic and respiratory dysfunction in clinical practice.Patients with an intra-abdominal source of infection were more likely to develop AKI.KDIGO criteria are reliable in AKI staging.

Early initiation renal replacement therapy for fluid management to reduce central venous pressure is more conducive to renal function recovery in patients with acute kidney injury

Background:Acute kidney injury (AKI) is a serious complication in critically ill patients with septic shock treated in the intensive care unit. Renal replacement therapy (RRT) is a treatment for severe AKI;however, the time of initiation of RRT and factors that affect the recovery of kidney function remains unclear. This study was to explore whether early initiation of RRT treatment for fluid management to reduce central venous pressure (CVP) can help to improve patients5 kidney function recovery. Methods: A retrospective analysis of septic patients who had received RRT treatment was conducted. Patients received RRT either within 12 h after they met the diagnostic criteria of renal failure (early initiation) or after a delay of 48 h if renal recovery had not occurred (delayed initiation). Parameters such as patients5 renal function recovery at discharge, fluid balance, and levels of CVP were assessed. Results: A total of 141 patients were eligible for enrolment: 40.4% of the patients were in the early initiation group (57 of 141 patients), and 59.6% were in the delayed initiation group (84 of 141 patients). There were no significant differences in the characteristics at baseline between the two groups, and there were no differences in 28-day mortality between the two groups (χ^2 = 2.142, P = 0.143);however, there was a significant difference in the recovery rate of renal function between the two groups at discharge (χ^2 = 4.730, P < 0.001). More importantly, early initiation of RRT treatment and dehydration to reduce CVP are more conducive to the recovery of renal function in patients with AKI. Conclusion: Compared with those who received delayed initiation RRT, patients who received early-initiation RRT for dehydration to reduce CVP have enhanced kidney function recovery.

Involvement of phosphatase and tensin homolog-induced putative kinase 1–Parkin-mediated mitophagy in septic acute kidney injury

Background:Studies have reported mitophagy activation in renal tubular epithelial cells(RTECs)in acute kidney injury(AKI).Phosphatase and tensin homolog-induced putative kinase 1(PINK1)and E3 ubiquitin-protein ligase Parkin are involved in mitophagy regulation;however,little is known about the role of PINK1-Parkin mitophagy in septic AKI.Here we investigated whether the PINK1-Parkin mitophagy pathway is involved in septic AKI and its effects on cell apoptosis in vitro and on renal functions in vivo.Methods:Mitophagy-related gene expression was determined using Western blot assay in human RTEC cell line HK-2 stimulated with bacterial lipopolysaccharide(LPS)and in RTECs from septic AKI rats induced by cecal ligation and perforation(CLP).Autophagy-related ultrastructural features in rat RTECs were observed using electron microscopy.Gain-and loss-of-function approaches were performed to investigate the role of the PINK1-Parkin pathway in HK-2 cell mitophagy.Autophagy activators and inhibitors were used to assess the effects of mitophagy modulation on cell apoptosis in vitro and on renal functions in vivo.Results:LPS stimulation could significantly induce LC3-II and BECN-1 protein expression(LC3-II:1.72±0.05 vs.1.00±0.05,P<0.05;BECN-1:5.33±0.57 vs.1.00±0.14,P<0.05)at 4 h in vitro.Similarly,LC3-II,and BECN-1 protein levels were significantly increased and peaked at 2 h after CLP(LC3-II:3.33±0.12 vs.1.03±0.15,P<0.05;BECN-1:1.57±0.26 vs.1.02±0.11,P<0.05)in vivo compared with those after sham operation.Mitochondrial deformation and mitolysosome-mediated mitochondria clearance were observed in RTECs from septic rats.PINK1 knockdown significantly attenuated LC3-II protein expression(1.35±0.21 vs.2.38±0.22,P<0.05),whereas PINK1 overexpression markedly enhanced LC3-II protein expression(2.07±0.21 vs.1.29±0.19,P<0.05)compared with LPS-stimulated HK-2 cells.LPS-induced proapoptotic protein expression remained unchanged in autophagy activator-treated HK-2 cells and was significantly attenuated in PINK1-overexpressing cells,but was remarkably upregulated in autophagy inhibitor-treated and in PINK1-depleted cells.Consistent results were observed in flow cytometric apoptosis assay and in renal function indicators in rats.Conclusion:PINK1-Parkin-mediated mitophagy might play a protective role in septic AKI,serving as a potential therapeutic target for septic AKI.

Non-pancreatic hyperlipasemia:A puzzling clinical entity

BACKGROUND Increased lipase level is a serological hallmark of the diagnosis of acute pancreatitis(AP)but can be detected in various other diseases associated with lipase leakage due to inflammation of organs surrounding the pancreas or reduced renal clearance and/or hepatic metabolism.This non-pancreatic hyperlipasemia(NPHL)is puzzling for attending physicians during the diagnostic procedure for AP.It would be clinically beneficial to identify the clinical and laboratory variables that hinder the accuracy of lipase diagnosis with the aim of improve it.A more precise description of the NPHL condition could potentially provide prognostic factors for adverse outcomes which is currently lacking.AIM To perform a detailed clinical and laboratory characterization of NPHL in a large prospective patient cohort with an assessment of parameters determining disease outcomes.METHODS A Hungarian patient cohort with serum lipase levels at least three times higher than the upper limit of normal(ULN)was prospectively evaluated over 31 months.Patients were identified using daily electronic laboratory reports developed to support an ongoing observational,multicenter,prospective cohort study called the EASY trial(ISRCTN10525246)to establish a simple,easy,and accurate clinical scoring system for early prognostication of AP.Diagnosis of NPHL was established based on≥3×ULN serum lipase level in the absence of abdominal pain or abdominal imaging results characteristic of pancreatitis.RESULTS A total of 808 patients[male,n=420(52%);median age(IQR):65(51-75)years]were diagnosed with≥3×ULN serum lipase levels.A total of 392 patients had AP,whereas 401 had NPHL with more than 20 different etiologies.Sepsis and acute kidney injury(AKI)were the most prevalent etiologies of NPHL(27.7%and 33.2%,respectively).The best discriminative cut-off value for lipase was≥666 U/L(sensitivity,71.4%;specificity,88.8%).The presence of AKI or sepsis negatively affected the diagnostic performance of lipase.NPHL was associated with a higher in-hospital mortality than AP(22.4%vs 5.1%,P<0.001).In multivariate binary logistic regression,not lipase but increased amylase level(>244 U/L)and neutrophil-to-lymphocyte ratio(NLR)(>10.37,OR:3.71,95%CI:2.006-6.863,P<0.001),decreased albumin level,age,and presence of sepsis were independent risk factors for in-hospital mortality in NPHL.CONCLUSION NPHL is a common cause of lipase elevation and is associated with high mortality rates.Increased NLR value was associated with the highest mortality risk.The presence of sepsis/AKI significantly deteriorates the serological differentiation of AP from NPHL.