Neutrophil gelatinase-associated lipocalin,kidney injury molecule-1,and periostin:Novel urinary biomarkers in diabetic nephropathy

BACKGROUND Globally,diabetic nephropathy(DN)is the primary cause of chronic kidney disease.Currently,renal function is monitored indirectly using measures of serum creatinine,estimated glomerular filtration rate(eGFR),and proteinuria.Novel urinary biomarkers utilized in the early stages of DN have been described;these indicators can be used in the early identification of the disease,which is important for initiating treatment to halt or impediment the advance of diabetic nephropathy.AIM To estimate neutrophil gelatinase-associated lipocalin(NGAL),kidney injury molecule-1(KIM-1),and periostin(POSTN)levels as novel urinary biomarkers in DN.METHODS In this hospital based cross-sectional study,a total of 160 patients of both genders aged 18 years or more;40 healthy participants and 120 patients with diabetes mellitus(DM)were included.Patients with DM were divided into normoalbuminuria(n=40),microalbuminuria(n=40),and macroalbuminuria(n=40)groups as per urine albumin creatinine ratio(uACR).Blood urea,serum creatinine,uACR were measured.Urine NGAL,KIM-1,and POSTN were measured by enzyme linked immunosorbent assay.The eGFR was calculated and compared with urinary markers.RESULTS NGAL,KIM-1,and POSTN levels increased significantly in normo,micro,and macroalbuminuria with the highest in the macroalbuminuria group.Albumin creatinine ratio(ACR)showed a positive correlation with NGAL,KIM-1,and POSTN levels.The eGFR showed a weak negative correlation with ACR,NGAL,KIM-1,and POSTN.NGAL was significantly lower in stage 1 compared to stage 2,3,and 4 kidney disease.KIM-1 was significantly decreased in stage 1 compared to stage 4 kidney disease.POSTN was significantly decreased in stage 1 compared to stage 3 and 4 kidney disease.The receiver operator curve analysis of ACR,NGAL,KIM-1,and POSTN showed good sensitivity of 80%,75.8%,63.3%,and 80%respectively with a cut-off of 12.5 mg/g,4.5μg/L,1.5 ng/mL,and 37.5 ng/mL.CONCLUSION Urinary NGAL and POSTN are independent markers of DN.

The Role for AVE0991 (MAS-Receptor Angiotensin II (1-7) Agonist) in Reducing Cisplatin-Induced Acute Kidney Injury on C57BL/6 Mice

Acute Kidney Injury (AKI) is a condition that causes nephrotoxicity in kidney tissues due to cisplatin-induced cancer treatments. Hence, it is proposed in this review that AVE0991 (a MAS-receptor Angiotensin II (1-7) agonist) may reduce cisplatin-induced acute kidney injury by promoting nitric oxide production.

Mechanism of miR-214-mediated HIF1 α and KIM1 signaling pathway in rats with ischemic acute kidney injury

Objective:To investigate the mechanism of mir-214-mediated HIF1 alpha and KIM1 signaling pathways in rats with ischemic acute kidney injury. Methods:Rats were divided into three groups according to the difference of the preparation model, 16 in each group, sham operation group, IAKI group and miR-214 group.The rats in the latter two groups were established with ischemic acute kidney injury. After 48 hours, three groups of rats were treated with orbital venous blood. Urine was collected, biochemical parameters and KIM1 expression were detected. After using Masson's Trichrome, TUNEL, immunoblotting and PCR, renal histopathology, apoptosis of glomerular epithelial cells and expression of HIF1α, KIM1 protein and mRNA in renal tissues were detected. Results:The biochemical parameters of rats in the IAKI group included Scr, BUN and 24hUTP, which were higher than the previous group (P<0.05). The MIR-214 group was higher than the IAKI group. The sham operation group had intact renal tissue structure and good renal tubular and glomeruli. The IAKIgroup had increased glomerular interstitial, renal interstitial widening and inflammation. Severe infiltration, severe tubular atrophy, miR-214 group and IAKIgroup, renal interstitial inflammation increased, hardness increased, tubular atrophy more serious;black yellow is apoptotic cells, IAKIgroup rat renal tubular epithelial cell apoptosis The most serious, the degree of apoptosis was significantly higher than the sham operation group;the degree of apoptosis of renal tubular epithelial cells was increased in the miR-214 group compared with the IAKIgroup, and high levels of miR-214 could accelerate the apoptosis of epithelial cellsThe HIF1α and KIM1 proteins in the IAKI group were higher than those in the Previous group(P<0.05). The above indexes in the mir-214 group were better than those in the IAKI group(P<0.05). The HIF1α and KIM1 mRNA in the IAKI group were higher than in the sham operation group, and the above indicators in the mir-214 group(P<0.05). Better than the IAKI group(P<0.05);Conclusions:The increase of miR-214 accelerates the apoptosis of glomerular epithelial cells, impaired renal tissue damage, and mediates the elevation of HIF1α and KIM1, further aggravating the condition of IAKI rats.

Urinary Kidney Injury Molocule-1 Level in Preterm Neonates with Respiratory Distress Syndrome

Background: Despite recent advances in perinatal and neonatal care in respiratory distress syndrome (RDS) prevention and treatment, a considerable number of these neonates suffer from acute kidney injury (AKI), and it is associated with poor outcome as an independent risk factor. KIM-1 mRNA and protein are expressed at a low level in normal kidney but are increased in post ischemic kidney. Aim: The aim is to detect the value of urinary KIM-1 measurement as an early predictor marker of acute kidney injury in preterm neonates with respiratory distress syndrome. Patients and methods: The study included 30 preterm newborn with (RDS) ≤36 weeks during the period from October 2014 to March 2015. Also the study included 30 apparently healthy newborn ≤36 weeks as controls. They were selected from NICU of Manshiate Elbakry hospital Cairo, Egypt. uKIM-1 along with serum creatinine levels and eGFR were assessed in days 1 of life for both groups and in day 3 for cases. Results: In day one of life, we found a significant increase in uKIM-1 levels in preterm newborn with RDS compared to their controls (2.88 ± 1.01 ng/ml and 0.95 ± 0.52 ng/ml respectively (p = 0.001)). There is no significant difference between both groups regarding serum creatinine and eGFR. In day 3 of life, preterm with RDS had significant decrease in uKIM-1 levels compared to day 1 of life with significant increase in non-survivor compared to survivor group ( 2.30 ± 1.56 ng/ml and 1.30 ± 0.90 ng/ml respectively (p = 0.03)). The sensitivity and specificity of uKIM-1 and serum creatinine was calculated (100.00%, 86.67% and 33.33%;95.00%) respectively. Conclusion: Preterm neonate with RDS is at high risk of developing AKI. Early and serial uKIM-1 measurements can be used as a non-invasive indicator of kidney injury in premature newborn with RDS.

Ginsenoside Rg1 and Resveratrol Alleviate Acute Kidney Injury Induced by Cisplatin via Downregulation of Autophagy in Mice

Background: Cisplatin, a chemotherapeutic agent, is widely used in the treatment of malignant tumors. Nephrotoxicity, especially acute kidney injury (AKI), is the most common and severe adverse reaction of cisplatin. Resveratrol and ginsenoside Rg1, two natural products, have been found to have renal protective effects. However, the effects and the mechanisms in cisplatin-induced AKI need further investigation. Methods: The mouse models of cisplatin-induced AKI and several treatment groups were established. Male C57BL/6 mice were divided into five groups: saline control group, cisplatin injury group, resveratrol treatment group, Rg1 treatment group, resveratrol and Rg1 combined treatment group. Serological analysis of serum urea nitrogen was aimed to reflect the function of kidney, and histological analysis of renal tissue sections was aimed to assess the damage of proximal convoluted tubules. The expression levels of autophagy-related proteins Beclin 1 and LC3 were detected by western blotting and qRT-PCR respectively. Results: The renal function was improved and renal damage was alleviated in Rg1 and resveratrol alone or combined treatment groups compared with the cisplatin injury group. For the mechanism, treatment with Rg1 and resveratrol alone or in combination decreased the expressions of Beclin 1 both at protein and mRNA levels, decreased LC3II/I protein levels, indicating that autophagy was inhibited by treatment with Rg1 and resveratrol alone or in combination. Conclusion: Resveratrol and Rg1 alleviated the kidney damage caused by cisplatin, and reduced autophagy was involved in the renoprotective effects of resveratrol and Rg1 against cisplatin-induced AKI. This study may provide new evidence to alleviate cisplatin-induced AKI.

Neutrophil gelatinase-associated lipocalin does not predict acute kidney injury in heart failure

BACKGROUND Acute cardiorenal syndrome type 1(CRS-1)is defined by a rapid cardiac dysfunction leading to acute kidney injury(AKI).Neutrophil gelatinaseassociated lipocalin(NGAL)is expressed on the surface of human neutrophils and epithelial cells,such as renal tubule cells,and its serum(sNGAL)and urinary have been used to predict AKI in different clinical settings.AIM To characterize CRS-1 in a cohort of patients with acute heart diseases,evaluating the potentiality of sNGAL as an early marker of CRS-1.METHODS We performed a retrospective cohort,multi-centre study.From January 2010 to December 2011,we recruited 202 adult patients admitted to the coronary intensive care unit(CICU)with a diagnosis of acute heart failure or acute coronary syndrome.We monitored the renal function to evaluate CRS-1 development and measured sNGAL levels within 24 h and after 72 h of CICU admission.RESULTS Overall,enrolled patients were hemodynamically stable with a mean arterial pressure of 92(82-107)mmHg,55/202(27.2%)of the patients developed CRS-1,but none of them required dialysis.Neither the NGAL delta value(AUC 0.40,95%CI:0.25-0.55)nor the NGAL peak(AUC 0.45,95%CI:0.36-0.54)or NGAL cutoff(≥140 ng/mL)values were statistically significant between the two groups(CRS-1 vs no-CRS1 patients).The area under the ROC curve for the prediction of CRS-1 was 0.40(95%CI:0.25-0.55)for the delta NGAL value and 0.45(95%CI:0.36-0.54)for the NGAL peak value.Finally,in multivariate analysis,the risk of developing CRS-1 was correlated with age>60 years,urea nitrogen at admission and 24 h-urine output(AUC 0.83,SE=60.5%SP=93%),while sNGAL was not significantly correlated.CONCLUSION In our population,sNGAL does not predict CRS-1,probably as a consequence of the mild renal injury and the low severity of heart disease.So,these data might suggest that patient selection should be taken into account when considering the utility of NGAL measurement as a biomarker of kidney damage.

Urine microscopy and neutrophilelymphocyte ratio are early predictors of acute kidney injury in patients with urinary tract infection

Objective:Urinary tract infection(UTI)is a common cause of morbidity and hospitalisation in the population worldwide.Upper UTI is indolent and causes subclinical acute kidney injury(AKI)resulting in preventable cause of scarring of renal parenchyma.We explored urinary and serum levels of kidney injury molecule-1(KIM-1),haematological parameters and quantitative urine microscopy parameters to predict kidney injury.Methods:Neutrophilelymphocyte ratio(NLR)is obtained by dividing absolute neutrophil count with absolute lymphocyte count.Quantitative urine sediment microscopy was performed and correlated with clinical,biochemical and haematological findings to predict AKI in patients with UTI.Quantitative ELISA was performed for serum and urine levels of KIM-1.Seventy two adult patients with UTI were enrolled,45 of whom had AKI while 27 were in the non-AKI group.Results:NLR(p=0.005)and renal tubular epithelial cell-granular cast score in quantitative urine microscopy(p=0.008)are strong predictors of AKI in patients with UTI while rest of quantitative urine microscopy parameters and serum and urinary levels of KIM-1 molecule were not found to be useful in prediction of AKI.Conclusion:NLR in haemogram is a novel and useful biomarker for predicting AKI in patients with UTI.

TOPK Activation Exerts Protective Effects on Cisplatin-induced Acute Kidney Injury

Objective:T-LAK-cell-originated protein kinase(TOPK),a PSD95-Disc large-ZO1(PDZ)binding kinase(PBK),is a novel member of the mitogen-activated protein kinase(MAPK)family.Studies have shown that TOPK plays a critical role in the function of tumor cells,including apoptosis and mitosis.However,little is known on the effect of TOPK in cisplatin-induced acute kidney injury(CP-AKI).This study aimed to investigate the role and mechanism of TOPK in CPAKI.Methods:Cisplatin was administered to C57BL/6 mice and cultured kidney tubular epithelial cells(TECs)to establish the CP-AKI murine or cellular models.TECs were then stimulated with the specific inhibitor of TOPK OTS514 or transfected with the recombinant-activated plasmid TOPK-T9E to inhibit or activate TOPK.The TECs were treated with AKT inhibitorⅧfollowing stimulation with OTS514 or cisplatin.Western blotting and flow cytometry were used to evaluate the cell cycle and apoptosis of TECs.Results:The analysis revealed that the TOPK activity was significantly suppressed by cisplatin,both in vivo and in vitro.Furthermore,the pharmacological inhibition of TOPK by OTS514,a specific inhibitor of TOPK,exacerbated the cisplatin-induced cell cycle arrest in the G2/M phase and apoptosis of cultured TECs.Moreover,the TOPK activation via the TOPK-T9E plasmid transfection could partially reverse the cell cycle arrest at the G2/M phase and apoptosis of cisplatin-treated TECs.In addition,AKT/protein kinase B(PKB),as a TOPK target protein,was inhibited by cisplatin in cultured TECs.The pharmaceutical inhibition of AKT further aggravated the apoptosis of TECs induced by cisplatin or TOPK inhibition.TOPK systematically mediated the apoptosis via the AKT pathway in the CP-AKI cell model.Conclusion:These results indicate that TOPK activation protects against CP-AKI by ameliorating the G2/M cell cycle arrest and cell apoptosis.

Levetiracetam-Associated Acute Kidney Injury and Drug Reaction with Eosinophilia and Systemic Symptoms (DRESS) Syndrome

DRESS syndrome is a severe drug induced reaction. Acute kidney injury (AKI) is sometimes present in the form of an acute interstitial nephritis. We present the case of a 75-year-old man with glioblastoma who developed a DRESS two months after starting levetiracetam and a few days after stopping dexamethasone. His skin and kidneys improved after removing levetiracetam and introducing again corticosteroids. DRESS has been reported more frequently with other antiepileptics, rarely with levetiracetam. Clinicians should add this drug to the list of potential causes of AKI.

Clinical efficacy and safety of flexible ureteroscopy and percutaneous nephrolithotomy for large kidney stones:A retrospective comparative study

BACKGROUND Renal stones ranging 20–40 mm are very common in China.Although no largesample clinical studies have confirmed the clinical efficacy and safety of this method,there is also a lack of comparative data with traditional treatment.AIM To investigate the clinical efficacy of flexible ureteroscopy(FURS)and percutaneous nephrolithotomy(PCNL)by postoperative stone clearance and changes in soluble vascular cell adhesion molecule 1(sVCAM-1)and kidney injury molecule 1(KIM-1)levels in patients with large kidney stones(>2 cm in diameter).METHODS This single-center observational study was performed at a Chinese hospital between January 1,2021,and October 30,2023.All 250 enrolled patients were diagnosed with large kidney stones(>2 cm)and divided into a FURS group(n=145)and a PCNL group(n=105)by the surgical method.The FURS group was treated with flexible ureteroscopy and the PCNL group was treated with percutaneous nephrolithotomy.The operation time,time to palinesthesia,intraoperative blood loss,drop in hemoglobin,length of hospital stay,stone clearance rate,and complications were recorded in the two groups.Preoperative and postoperative serum sVCAM-1 levels,erythrocyte sedimentation rate(ESR),urine KIM-1 levels,preoperative and postoperative pain visual analog scale(VAS)and Wisconsin Stone Quality of Life Questionnaire(WISQOL)scores were also documented.RESULTS All 250 eligible patients completed the follow-up.There were no significant differences in baseline characteristics between the two groups(P>0.05).The operation time in the FURS group was significantly greater than that in the PCNL group.The time to ambulation,intraoperative blood loss,decrease in hemoglobin,and length of hospital stay were significantly lower in the FURS group than in the PCNL group.The FURS group also had a significantly higher stone clearance rate and a lower incidence of postoperative complications.There was no significant difference in antibiotic use between the groups.Postoperative serum sVCAM-1 levels,urine KIM-1 levels,and VAS scores were lower in the FURS group than in the PCNL group,but postoperative ESR and WISQOL scores were greater in the FURS group than in the PCNL group.CONCLUSION FURS demonstrated superior clinical efficacy in treating large kidney stones(>2 cm in diameter)compared PCNL.It not only improved the postoperative stone clearance rate and reduced complications and recovery time but also positively affected serum SCM-1,ESR,and urine KIM-1 levels,subsequent improvement of patient quality of life.

Prognostic Factors in Cardiorenal Syndrome Type 1: Retrospective Observational and Analytical Study

Introduction: Type 1 cardiorenal syndrome (CRS 1) is characterized by acute impairment of cardiac function leading to acute renal dysfunction. CRS1 is present in 25% of patients admitted for heart failure. The objective of our study is to analyze the epidemiological, clinical, therapeutic profile and the risk and prognostic factors of these patients. Materials and Methods: We identified 120 patients with cardiorenal syndrome (CRS) over a one-year period to determine the prevalence and risk factors for developing CRS 1. We analyzed the clinical, biological, and evolutionary profiles of patients with CRS 1 and determined the risk factors for the occurrence of acute kidney injury (AKI) as well as the mortality factors in these patients. Résultats: The average age of our patients with CRS1 is 58 ± 9 years, with a sex ratio of 1.4. The average eGFR of our patients is 35 ± 6.5 ml/min/1.73m2. Diabetes was found in 17% of our patients and hypertension in 14%. The etiology of cardiac impairment is predominantly acute coronary syndrome (ACS), followed by rhythm disorders. Renally, all our patients have acute kidney injury (AKI), with 86% having functional acute renal failure and 14% having acute tubular necrosis. Therapeutically, 50% of our patients are on diuretics, 42% receive beta-blocker treatment, and RAAS blockers are used in 29% of cases. Renal replacement therapy (RRT) sessions were required in 13.8% of cases. In univariate analysis, male gender, tachyarrhythmia, and hypertension are associated with the early onset of acute kidney injury (AKI). The use of diuretics, anemia, and low left ventricular ejection fraction (LVEF) are linked to a higher risk of developing CRS 1 (p = 0.021, p = 0.037, p = 0.010 respectively). In multivariate analysis, advanced age is significantly associated with increased mortality risk in CRS 1 patients (p = 0.030), while beta-blocker use is considered a protective factor (p = 0.014). Conclusion: Our study identifies several key factors associated with outcomes in type 1 CRS. Male gender, tachyarrhythmia, and hypertension are linked to early-onset AKI. The use of diuretics and the presence of anemia increase the risk of developing CRS1. Advanced age is significantly associated with higher mortality rates. Conversely, the use of beta-blockers appears to be protective in this patient population. .

环孢素引起肾小管上皮细胞培养液中肾损伤分子-1水平升高的机制

目的:探讨环孢素(CsA)引起人肾小管上皮细胞(HKC)培养液中肾损伤分子-1(KIM-1)水平升高的作用机制,阐明KIM-1表达与p38 MAPK通路和EKR1/2 MAPK通路的关系。方法:将处于对数生长期的HKC分为空白组、CsA损伤组、CsA与p38激酶抑制剂合用组、p38激酶抑制剂组、CsA与ERK1/2激酶抑制剂合用组和ERK1/2激酶抑制剂组。MTT法检测各组HKC增殖抑制率,ELISA法测定各组HKC上清液中KIM-1水平,流式细胞术检测各组细胞存活率、细胞凋亡率和细胞坏死率。结果:与空白组比较,CsA损伤组细胞上清液中KIM-1水平显著升高(P<0.05),细胞存活率显著降低(P<0.05),细胞凋亡率和细胞坏死率显著升高(P<0.05);p38激酶抑制剂组和ERK1/2激酶抑制剂组中细胞存活率、细胞凋亡率和细胞坏死率比较差异无统计学意义(P>0.05)。与CsA损伤组比较,CsA与p38激酶抑制剂合用组、CsA与ERK1/2激酶抑制剂合用组细胞上清液中KIM-1水平显著降低(P<0.05),细胞存活率显著升高(P<0.05),细胞凋亡率和细胞坏死率显著降低(P<0.05)。结论:p38 MAPK通路和ERK1/2 MAPK通路参与CsA素引起肾小管上皮细胞培养液中KIM-1水平升高的过程,KIM-1的表达可能成为临床监测CsA肾毒性的生化指标。

体外循环心脏不停跳二尖瓣置换术围术期肾损伤分子-1的变化

目的研究体外循环(CPB)心脏不停跳与停跳二尖瓣置换术(MVR)围术期尿肾损伤分子-1(KIM-1)的变化规律,探讨心脏不停跳手术对患者肾功能的影响。方法选择需行MVR患者40例,按随机数字表分为不停跳组和停跳组,每组各20例。检测术前(T1)、CPB后30 min(T2)、2 h(T3)、术后24 h(T4)、72 h(T5)的KIM-1浓度。结果组内不同时间点的KIM-1浓度差异有统计学意义(P<0.05),随着时间延长两组KIM-1浓度上升,但不停跳组术后72 h恢复至正常水平,而停跳组72 h后仍未能恢复至术前水平。不停跳组KIM-1浓度低于停跳组(P<0.05)。结论 CPB心脏不停跳MVR患者围术期尿KIM-1浓度变化较小,心脏不停跳手术或可减少肾功能损害。

CD36 promotes tubular ferroptosis by regulating the ubiquitination of FSP1 in acute kidney injury

Reactive oxidative species(ROos)production-driven ferroptosis plays a role in acute kidney injury(Akl).However,its exact molecular mechanism is poorly understood.Scavenger receptor CD36 has important roles in oxidizing lipids,lipid accumulation,metabolic syndrome,and insulin resistance in chronic kidney disease,but its roles remain unexplored in AKl.The present study investigated the role and mechanism of CD36 in regulating proximal tubular cell ferroptosis and AKl.The expression of CD36 was found to be significantly up-regulated in AKI renal tissues and correlated with renal function,which might serve as an independent biomarker for AKl patients.Moreover,in adult mice subjected to AKl,deletion of CD36(CD36-/-)induced tubular cell Ros accumulation,ferroptosis activation,and renal injury.Mechanistically,combining LC-MS/MS,co-IP,and ubiquitination analyses revealed that CD36 could specifically bind to ferroptosis suppressor protein 1(FSP1)and regulate its ubiquitination at sites K16 and K24,leading to FSP1 degradation and progression of ferroptosis in AKl.The present results emphasize a novel mechanism of CD36 in cisplatin-induced AKl.The discovery of the special CD36 roles in promoting ferroptosis and AKI development by regulating the ubiquitination of FSP1 in proximal tubular cells may be potential therapeutic targets for AKl.Moreover,CD36 may play a key role in the progression of AKl.Therefore,targeting CD36 may provide a promising treatment option for AKI.

A novel marine-derived anti-acute kidney injury agent targeting peroxiredoxin 1 and its nanodelivery strategy based on ADME optimization

Insufficient therapeutic strategies for acute kidney injury(AKI)necessitate precision therapy targeting its pathogenesis.This study reveals the new mechanism of the marine-derived anti-AKI agent,piericidin glycoside S14,targeting peroxiredoxin 1(PRDX1).By binding to Cys83 of PRDX1 and augmenting its peroxidase activity,S14 alleviates kidney injury efficiently in Prdx1-overexpression(Prdx1-OE)mice.Besides,S14 also increases PRDX1 nuclear translocation and directly activates the Nrf2/HO-1/NQO1 pathway to inhibit ROS production.Due to the limited druggability of S14 with low bioavailability(2.6%)and poor renal distribution,a pH-sensitive kidney-targeting dodecanaminechitosan nanoparticle system is constructed to load S14 for precise treatment of AKI.L-Serine conjugation to chitosan imparts specificity to kidney injury molecule-1(Kim-1)-overexpressed cells.The developed S14-nanodrug exhibits higher therapeutic efficiency by improving the in vivo behavior of S14 significantly.By encapsulation with micelles,the AUC_(0-t),half-life time,and renal distribution of S14 increase 2.5-,1.8-,and 3.1-fold,respectively.The main factors contributing to the improved druggability of S14 nanodrugs include the lower metabolic elimination rate and UDPglycosyltransferase(UGT)-mediated biotransformation.In summary,this study identifies a new therapeutic target for the marine-derived anti-AKI agent while enhancing its ADME properties and druggability through nanotechnology,thereby driving advancements in marine drug development for AKI.

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.

Value of urine IL-8, NGAL and KIM-1 for the early diagnosis of acute kidney injury in patients with ureteroscopic lithotripsy related urosepsis

Purpose::To investigate the clinical value of urine interleukin-18(IL-8),neutrophil gelatinase-associated lipocalin(NGAL)and kidney injury molecule-1(KIM-1)for the early diagnosis of acute kidney injury(AKI)in patients with ureteroscopic lithotripsy(URL)related urosepsis.Methods::A retrospective study was carried out in 157 patients with urosepsis after URL.The patients were divided into AKI group and non-AKI group according to the Kidigo guideline and urine IL-8,NGAL and KIM-1 levels were detected by enzyme-linked immunosorbent assay at 0,4,12,24 and 48 h after the surgery.Receiver operating characteristic curve(ROC)was used to evaluate the diagnostic value of these three biomarkers for postoperative AKI.Results::The level of urine IL-8,NGAL and KIM-1 in AKI group was significantly higher than that in non-AKI group at 4,12,24 and 48 h(p<0.01).The ROC analysis showed the combined detection of urine IL-8,NGAL and KIM-1 at 12 h had a larger area under curve(AUC)than a single marker(0.997,95%CI:0.991-0.998),and the sensitivity and specificity were 98.2%and 96.7%,respectively.Pearson correlation analysis showed that the levels of urine NGAL at 4,12,24 and 48 h in AKI patients were positively correlated with the levels of urine KIM-1 and IL-18(p<0.01).Conclusion::AKI could be quickly recognized by the elevated level of urine IL-8,NGAL and KIM-1 in patients with URL-related urosepsis.Combined detection of the three urine biomarkers at 12 h after surgery had a better diagnostic performance,which may be an important reference for the early diagnosis of AKI.

Resolvin D1 Protects Lipopolysaccharide-induced Acute Kidney Injury by Down-regulating Nuclear Factor-kappa B Signal and Inhibiting Apoptosis

Background： Resolvin D1 （RvD1） is a newly found anti-inflammatory bioactive compound derived from polyunsaturated fatty acids. The current study aimed to explore the protective effect of RvD1 on lipopolysaccharide （LPS）-induced acute kidney injury （AKI） and its possible mechanism. Methods： Both in vivo and in vitro studies were conducted. Male BALB/c mice were randomly divided into control group （saline）, LPS group （LPS 5 mg/kg）, RvD1 group （RvD1 5 μg/kg ＋ LPS 5 mg/kg）, and blockage group （Boc-MLP 5 gg/kg ＋ RvD1 5 gg/kg ＋ LPS 5 mg/kg）. Boc-MLP is a RvD 1 receptor blocker. The mice were intraperitoneally injected with these drugs and recorded for general condition for 48 h, while the blood and kidneys were harvested at 2, 6, 12, 24, and 48 h time points, respectively （n = 6 in each group at each time point）. Human proximal tubule epithelial cells （HK-2） were randomly divided into control group （medium only）, LPS group （LPS 5 μg/ml）, RvD1 group （RvD1 10 ng/ml ＋ LPS 5 μg/ml）, and blockage group （Boc-MLP 10 ng/ml ＋ RvD1 10 ng/ml ＋ LPS 5 μg/ml）. The cells were harvested for RNA at 2, 4, 6, 12, and 24 h time points, respectively （n = 6 in each group at each time point）. Blood creatinine was tested by using an Abbott i-STAT portable blood gas analyzer. Tumor necrosis factor-α （TNF-α level was detected by EL1SA. Kidney pathology was observed under hematoxylin and eosin （HE） staining and transmission electron microscope （TEM）. We hired immune-histological staining, Western blotting, and fluorescence quantitative polymerase chain reaction to detect the expression of RvD1 receptor ALX, nuclear factor-kappa B （NF-KB） signaling pathway as well as caspase-3. Kidney apoptosis was evaluated by TUNEL staining. Results： RvD 1 receptor ALX was detected on renal tubular epithelials. Kaplan-Meier analysis indicated that RvD 1 improved 48 h animal survival （80%） compared with LPS group （40%） and RvDI blockage group （60%）, while RvD1 also ameliorated kidney pathological injury in HE staining and TEM scan. After LPS stimulation, the mRNA expression of toll-like receptor 4, myeloid differentiation factor 88, and TNF-α in both mice kidneys and HK-2 cells were all up-regulated, while RvDI substantially inhibited the up-regulation of these genes. Western blotting showed that the phosphorylated-IKB/IKB ratio in LPS group was significantly higher than that in the control group, which was inhibited in the RvD1 group. RvD1 could inhibit the up-regulation of cleaved-caspase-3 protein stimulated by LPS, which was prohibited in RvD 1 blockage group. RvD 1 group also had a lower proportion of apoptotic nuclei in mice kidney by TUNEL staining compared with LPS group. Conclusion： In LPS-induced AKI, RvD1 could decrease TNF-α level, ameliorate kidney pathological injury, protect kidney function, and improve animal survival by down-regulating NF-KB inflammatory signal as well as inhibiting renal cell apoptosis.

Kidney injury molecule-1 is a potential receptor for SARS-CoV-2

COVID-19 patients present high incidence of kidney abnormalities,which are associated with poor prognosis and mortality.The identification of SARS-CoV-2 in the kidney of COVID-19 patients suggests renal tropism of SARS-CoV-2.However,whether there is a specific target of SARS-CoV-2 in the kidney remains unclear.Herein,by using in silico simulation,coimmunoprecipitation,fluorescence resonance energy transfer,fluorescein isothiocyanate labeling,and rational design of antagonist peptides,we demonstrate that kidney injury molecule-1(KIM1),a molecule dramatically upregulated upon kidney injury,binds with the receptor-binding domain(RBD)of SARS-CoV-2 and facilitates its attachment to cell membrane,with the immunoglobulin variable Ig-like(Ig V)domain of KIM1 playing a key role in this recognition.The interaction between SARS-CoV-2 RBD and KIM1 is potently blockaded by a rationally designed KIM1-derived polypeptide AP2.In addition,our results also suggest interactions between KIM1 Ig V domain and the RBDs of SARS-CoV and MERS-CoV,pathogens of two severe infectious respiratory diseases.Together,these findings suggest KIM1 as a novel receptor for SARS-CoV-2 and other coronaviruses.We propose that KIM1 may thus mediate and exacerbate the renal infection of SARS-CoV-2 in a‘vicious cycle’,and KIM1 could be further explored as a therapeutic target.

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.