Kidney Injury Score Research Articles

Necrotizing soft tissue infections - a multicentre, prospective observational study (INFECT): protocol and statistical analysis plan.

The INFECT project aims to advance our understanding of the pathophysiological mechanisms in necrotizing soft tissue infections (NSTIs). The INFECT observational study is part of the INFECT project with the aim of studying the clinical profile of patients with NSTIs and correlating these to patient-important outcomes. With this protocol and statistical analysis plan we describe the methods used to obtain data and the details of the planned analyses. The INFECT study is a multicentre, prospective observational cohort study. Patients with NSTIs are enrolled in five Scandinavian hospitals, which are all referral centres for NSTIs. The primary outcomes are the descriptive variables of the patients. Secondary outcomes include identification of factors associated with 90-day mortality and amputation; associations between affected body part, maximum skin defect and Laboratory Risk Indicator for Necrotizing Fasciitis (LRINEC) score and 90-day mortality; 90-day mortality in patients with and without acute kidney injury (AKI) and LRINEC score of six and above or below six; and association between affected body part at arrival and microbiological findings. Exploratory outcomes include univariate analyses of baseline characteristics associations with 90-day mortality. The statistical analyses will be conducted in accordance with the predefined statistical analysis plan. Necrotizing soft tissue infections result in severe morbidity and mortality. The INFECT study will be the largest prospective study in patients with NSTIs to date and will provide important data for clinicians, researchers and policy makers on the characteristics and outcomes of these patients.

Combination therapy of exendin-4 and allogenic adipose-derived mesenchymal stem cell preserved renal function in a chronic kidney disease and sepsis syndrome setting in rats.

Combined therapy with exendin-4 (Ex4) and allogenic adipose-derived mesenchymal stem cells (ADMSC) was tested against either therapy alone for protecting kidney function against chronic kidney disease (CKD) complicated by sepsis syndrome (SS) [i.e., by intraperitoneal injection of cecal-derived bacteria (1.0 × 104) cells/milliliter/total 5.0 cc].Adult-male-Sprague Dawley rats (n=36) were equally divided into group 1 (sham-control), group 2 (CKD), group 3 (CKD-SS), group 4 (CKD-SS-Ex4), group 5 (CKD-SS-ADMSC) and group 6 (CKD-SS-Ex4-ADMSC). At day 42 after CKD induction SS was induced. Thirty-minutes after SS induction, ADMSCs (2.0 ×106 cells) were intravenously administered to groups 5 and 6. Ex4 (10 μg/kg) was intraperitoneally administered groups 4 and 6 at 30 min and days 1 to 5 after SS induction. Animals were euthanized at day 47 after CKD induction. Kidney-injury score, collagen-deposition area, and creatinine/BUN levels were lowest in group 1, highest in group 3 and significantly higher in group 2 than in groups 4 to 6 in a progressively increasing manner (all P<0.0001). Protein expressions of inflammatory (MMP-9/TNF-α/NF-κB/IL-1ß/ICAM-1), oxidative-stress (NOX-1/NOX-2/oxidized protein), apoptotic (mitochondrial-Bax/cleaved-caspase-3/cleaved-PARP) and fibrotic/DNA-damaged (Smad3/TGF-ß/γ-H2AX) biomarkers showed an identical pattern, whereas anti-fibrotic (BMP-2/Smad1/5), anti-apoptotic/endothelial-integrity (Bcl-2/eNOS) and podocyte-integrity (ZO-1/p-cadherin) biomarkers exhibited an opposite pattern of kidney-injury score among the six groups (all P>0.0001). Cellular expressions of inflammatory (CD14/CD68) and glomerulus/tubular-injury (WT-1/KIM-1) biomarkers displayed an identical pattern, whereas glomerulus/podocyte-component (dystroglycan/nephrin/ZO-1/fibronectin/p-cadherin) biomarkers showed an opposite kidney-injury score among the six groups (all P<0.0001). In conclusion, Ex4-ADMSC therapy effectively preserved renal function in the CKD-SS setting.

Abstract 049: Prevention of Glomerular Hyperfiltration by Enhancement of Tubuloglomerular Feedback Response Induces Hypertension and Exacerbates Diabetic Kidney Injury

The mechanism underlying the higher prevalence of hypertension in diabetes remains unclear. We hypothesized that blunted tubuloglomerular feedback (TGF) mediated by the neuronal nitric oxide synthesis (NOS1) β in the macula densa promotes glomerular hyperfiltration in diabetes, whereas inadequate NOS1β in the macula densa restricts glomerular hyperfiltration, induces hypertension and exacerbates diabetic kidney injury. First, we measured the protein levels of NOS1β in the renal cortex, which was 6.5±1.2 fold higher in db/db mice than in db/+ mice (n=5, p&lt;0.01). Then, in isolated and perfused juxtaglomerular apparatus, we measured TGF-induced NO generation by the macula densa, which was 115.4±9.8 Units/min in db/+ mice and 161.5±12.7 Units/min in db/db mice (n=5, p&lt;0.01). We next measured TGF in vivo using micropuncture, which was 3.7±0.4 mmHg in db/db mice and 5.3±0.3 mmHg in db/+ mice (n=5, p&lt;0.05). Then we developed a macula densa specific NOS1 knockout db/db mouse line (KO) (Lepr db/db ; NKCC2 cre ; NOS1 flox/flox ). Littermate db/db (Lepr db/db ; NOS1 flox/flox ) and db/+ (Lepr db/+ ; NOS1 flox/flox ) mice serve as diabetic and non-diabetic controls. Glomerular filtration rate (GFR) was 236±18 μl/min in db/+ mice, and significantly increased to 375±12 and 284±11 μl/min in the db/db and KO mice (n=4-5, p&lt;0.01). Telemetric mean arterial pressure (MAP) was 97.1±3.5 and 103.6±5.2 mmHg in db/+ and db/db mice, and significantly raised to 124.4±8.1 mmHg in the KO mice (n=4-5, p&lt;0.01). Proteinuria increased by 70 and 120 folds in the db/db and KO mice compared with db/+ mice (n=4, p&lt;0.01). The kidney histology was assessed with light and transmission electron microscopy in the mice at age of 24 weeks. The diabetic kidney injury score was 0.37±0.16 in the db/+ mice, and significantly increased to 1.14±0.2 and 2.37±0.67 in the db/db and KO mice (n=5, p&lt;0.01). In conclusion, upregulation of the macula densa NOS1 blunts TGF response and promotes elevation of GFR in diabetes. Contrary to popular belief about glomerular hyperfiltration in diabetes, our data suggest that directly limiting the increase in GFR by enhancement of TGF response is detrimental, which induces hypertension and exacerbates diabetic kidney injury.

Xenogeneic human umbilical cord-derived mesenchymal stem cells reduce mortality in rats with acute respiratory distress syndrome complicated by sepsis.

This study tested the hypothesis that xenogeneic human umbilical cord-derived mesenchymal stem cell (HUCDMSC) therapy would improve survival rates in rats with acute respiratory distress-syndrome (ARDS, induction by 48 h inhalation of 100% oxygen) and sepsis-syndrome (SS, induction by cecal-ligation and puncture) (ARDS-SS). Adult-male Sprague-Dawley rats were categorized into group 1 (sham-controls), group 2 (ARDS-SS), group 3 [ARDS-SS+HUCDMSC (1.2 ×106 cells administered 1 h after SS-induction)], and group 4 [ARDS-SS+HUCDMSC (1.2 ×106 cells administered 24 h after SS-induction)]. The mortality rate was higher in groups 2 and 4 than in groups 1 and 3 (all p<0.0001). The blood pressure after 28 h was lower in groups 2, 3 and 4 (p<0.0001) than in group 1. Albumin levels and percentages of inflammatory cells in broncho-alveolar lavage fluid, and the percentages of inflammatory and immune cells in circulation, were lowest in group 1, highest in group 2, and higher in group 3 than group 4 (all p<0.0001). The percentages of inflammatory cells in ascites and kidney parenchyma showed identical patterns, as did kidney injury scores (all p<0.0001). EarlyHUCDMSC therapy reduced rodent mortality after induced ARDS-SS.

Fluid Overload and Kidney Injury Score: A multidimensional real-time assessment of renal disease burden in the critically ill patient

目的 据报道，对间歇急性肾损伤(acute kidney injury，AKI)进行预警可降低成人AKI相关病死率。危重症儿童AKI风险因子较多；尽管已通过标准化定义提高了对此病的认识，血清肌酐微小变化增加了AKI识别难度。年龄及体型的可变性导致肌酐阈值不统一，肾毒性药物暴露很常见，但并未列入肾损伤评分。现有疾病危重度测量法并不包括液体超负荷(fluid overload，FO)，而其为一项描述良好的病死率风险因子。本研究假定在维持或改善不良预后相关度测量时，相比于传统AKI分期，多维肾脏情况测量可更好描述疾病的肾脏受累严重度。 对象及场所 一家独立儿童医院四级PICU 18个月收治的所有患儿。 设计 新制定一项联合AKI，FO≥15%及肾毒性暴露情况的实时多维肾脏情况测量法，即液体超负荷肾损伤评分(fluid overload kidney injury score，FOKIS)且前瞻性用于所有患儿。出院或病死前FOKIS峰值被用于评估预后相关性。 干预措施 无 结果 2 830例PICU患儿(中位年龄5.5年，IQR 1.3～12.9，男性55%)FOKIS峰值波动于0～14分，66%患儿FOKIS≥1分。控制年龄、儿童病死率风险评分-3(pediatric risk of mortality-3，PRISM-3)、呼吸机、升压药及肾替代治疗后，FOKIS与PICU病死率及PICU/总住院时长独立相关(P＝0.047)。FOKIS由0到8＋，病死率由1.5%升至40%。除外尿量因素后，FOKIS与病死率相关性强于FO或AKI。 结论 该肾脏疾病负担多维评分与PICU不良预后显著相关。进一步研究将评估FOKIS能否作为一项预警及决策支持工具影响以患者为中心的预后。

Enhanced protection against renal ischemia-reperfusion injury with combined melatonin and exendin-4 in a rodent model.

We tested the hypothesis that combined treatment with melatonin, an anti-oxidant, and exendin-4, an anti-inflammatory agent, was superior to either alone for protecting the kidney from ischemia-reperfusion (IR) injury. Male adult Sprague-Dawley rats (n=40) were equally divided into group 1 (sham-operated control), group 2 (IR only, IR=1h/72h), group 3 (IR-exendin-4, 10 µg/kg at 30 min, 24 h, 48 h after IR procedure), group 4 (IR-melatonin, i.p. 50 mg at 30 min, then 20 mg at 6 and 18 h after IR procedure), and group 5 (combined IR-exendin-4-melatonin). All animals were sacrificed by 72 h after IR/sham procedure. The results showed that the kidney injury score, plasma creatinine, and blood urea nitrogen (BUN) levels were highest in group 2 and lowest in group 1, significantly higher in groups 3 and 4 than those in group 5 and significantly higher in group 3 than those in group 4 (all p < 0.001). The protein expressions of inflammatory (toll-like receptor 4, inducible nitric oxide synthase, interleukin-1β), apoptotic (mitochondrial Bax, cleaved caspase-3 and poly(ADP-ribose) polymerase, p53), podocyte integrity (E-cadherin, P-cadherin), and cell survival (phosphatidylinositol-3-kinase/AKT/mammalian target of rapamycin) biomarkers, as well the podocyte dysfunction biomarkers (Wnt1/Wnt4/β-catenin) displayed a pattern identical to that of creatinine level among the five groups (all p < 0.001). Microscopic findings demonstrated that podocyte dysfunction (Wnt1/Wnt4/β-catenin expression) and inflammatory (CD14 and F4/80-positively stained cells) biomarkers exhibited an identical pattern, whereas that of antioxidant (HO-1(+), NQO-1(+) cells) biomarkers showed an opposite pattern compared to that of creatinine level among the five groups (all p < 0.001). Combined melatonin-exendin-4 therapy offered an additional benefit in protecting the kidney from acute IR injury.

Combination of adipose-derived mesenchymal stem cells (ADMSC) and ADMSC-derived exosomes for protecting kidney from acute ischemia–reperfusion injury

BackgroundIn this study, we tested the hypothesis that a combined adipose-derived mesenchymal stem cell (ADMSC) and ADMSC-derived exosome therapy protected rat kidney from acute ischemia–reperfusion (IR) injury (i.e., ligation of both renal arteries for 1h and reperfusion for 72h prior to euthanization). Methods and resultsAdult-male SD rats (n=40) were equally categorized into group 1 (sham control), group 2 (IR), group 3 [IR+exosome (100μg)], group 4 [IR+ADMSC (1.2×106 cells)], and group 5 (IR-exosome-ADMSC). All therapies were performed at 3h after IR procedure from venous administration. By 72h, the creatinine level and kidney injury score were the lowest in group 1 and the highest in group 2, significantly higher in group 3 than in groups 4 and 5, and significantly higher in group 4 than in group 5 (all P<0.0001). The protein expression of inflammatory (TNF-α/NF-κB/IL-1β/MIF/PAI-1/Cox-2), oxidative-stress (NOX-1/NOX-2/oxidized protein), apoptotic (Bax/caspase-3/PARP), and fibrotic (Smad3/TGF-β) biomarkers showed an identical pattern, whereas the anti-apoptotic (Smad1/5, BMP-2) and angiogenesis (CD31/vWF/angiopoietin) biomarkers and mitochondrial cytochrome-C showed an opposite pattern of creatinine level among the five groups (all P<0.001). The microscopic findings of glomerular-damage (WT-1), renal tubular-damage (KIM-1), DNA-damage (γ-H2AX), inflammation (MPO/MIF/CD68) exhibited an identical pattern, whereas the podocyte components (podocin/p-cadherin/synaptopodin) displayed a reversed pattern of creatinine level (all P<0.0001). ConclusionCombined exosome–ADMSC therapy was superior to either one for protecting kidney from acute IR injury.

Combined Therapy With Adipose-Derived Mesenchymal Stem Cells and Ciprofloxacin Against Acute Urogenital Organ Damage in Rat Sepsis Syndrome Induced by Intrapelvic Injection of Cecal Bacteria.

We hypothesized that combined treatment with autologous adipose-derived mesenchymal stem cell (ADMSC) and ciprofloxacin is superior to ciprofloxacin only in reducing sepsis-induced urogenital organ damage and mortality in rat sepsis syndrome (SS) caused by intrapelvic injection of cecal bacteria (1.0 × 10(4) cells per milliliter; total, 5.0 ml). Male Sprague-Dawley rats (n = 60) equally divided into group 1 (sham-control), group 2 (SS), group 3 (SS-ADMSC [5.0 × 10(5) intravenously at 0.5, 6, and 18 hours after sepsis induction]), group 4 (SS-ciprofloxacin [3.0 mg/kg, b.i.d.] for 5 days), and group 5 (SS-ADMSC-ciprofloxacin) were sacrificed by day 5. Mortality rate and creatinine level were highest in group 2 and lowest in group 1 and significantly higher in groups 3 and 4 than those in group 5, but there was no difference between groups 3 and 4 (all p < .005). The kidney injury score, inflammatory biomarker expressions at protein (tumor necrosis factor-1α, nuclear factor-κB, matrix metallopeptidase-9, regulated on activation, normal T-cell expressed and secreted, interleukin-1β) and cellular (CD14+, migratory inhibitor factor positive, CD68+) levels in kidneys and urinary bladder were lowest in group 1 and highest in group 2, higher in group 4 than in groups 3 and 5, and higher in group 3 than in group 5 (all p < .001). Protein expressions of apoptosis (Bax, cleaved caspase 3 and poly[ADP-ribose] polymerase 1, p21 protein [Cdc42/Rac]-activated kinase 2) and oxidative stress (oxidized protein, NADPH oxidase (NOX)-1, NOX-2) in these organs showed an identical pattern compared with that of inflammation in all groups (all p < .001). In conclusion, ADMSC-assisted ciprofloxacin therapy offered an additional benefit by reducing acute urogenital organ damage in rat. Autologous adipose-derived mesenchymal stem cell-assisted ciprofloxacin therapy offered an additional benefit by reducing acute urogenital organ damage in rats.

A Score for Predicting Acute Kidney Injury After Coronary Artery Bypass Graft Surgery in an Asian Population.

To develop a scoring system to predict acute kidney injury in Asian patients after coronary artery bypass grafting. A retrospective analysis of data collected in an institutional cardiac database. A tertiary academic hospital in a large metropolitan city. The study comprised 954 patients with coronary artery disease. All patients underwent coronary artery bypass surgery with cardiopulmonary bypass but did not undergo any other concomitant procedures. The main outcome measured was acute kidney injury as defined by the Acute Kidney Injury Network criteria. The following 6 clinical variables were independent predictors of kidney injury: age>60 years, diabetes requiring insulin, estimated glomerular filtration rate<60 mL/min/1.73 m(2), ejection fraction<40%, cardiopulmonary bypass time>140 minutes, and aortic cross-clamp time>100 minutes. These variables were used to develop the Singapore Acute Kidney Injury score. The Singapore Acute Kidney Injury score is a simple way to predict, at the time of admission to the intensive care unit, an Asian patient's risk of developing acute kidney injury after coronary artery bypass surgery.

Effects of N-acetylcysteine and ethyl pyruvate on ischemia-reperfusion injury in experimental electrical burn model

ObjectivesThis study was planned as a histopathologic evaluation of the effectiveness of ethyl pyruvate (EP) and N-acetylcysteine (NAC) in reducing electric burn–related organ damage in an experimental model. MethodsFour groups of 7 female Wister rats were established. The first was a sham group, the second an electrical burn control group receiving 600 V, the third group received NAC therapy of 20 mg/kg 1 hour after 600 V electrical burn, and the fourth group received 50 mg/kg EP 1 hour after 600 V electrical burn. Heart, kidney, striated muscle, brain, and lung tissues obtained 24 hours postprocedurally were subjected to histopathologic examination, and injury scores were determined. The values determined were then subjected to statistical analysis. ResultsElectrical fire caused significant damage in heart, striated muscle, kidney, and brain tissues. A statistically significant decrease in injury scores in total striated muscle and heart tissue was observed in the 2 treatment groups administered NAC or EP compared to the control group (P= .001). Total kidney injury scores among the groups were significantly lower in the NAC and EP groups compared to the control group (P= .002 and P= .001, respectively). Brain injury examination revealed a significant decrease in injury scores with NAC and EP therapy, both antioxidant agents, in terms of neuron degeneration (P= .004 and P= .001, respectively). ConclusionsElectrical burn was observed to cause injury in heart, striated muscle, kidney, and brain tissue. This injury was reduced by the administration of NAC and EP.

Combined melatonin and exendin-4 therapy preserves renal ultrastructural integrity after ischemia-reperfusion injury in the male rat.

We tested whether combined melatonin (Mel) and exendin-4 (Ex4) treatment can better preserve glomerular structural integrity after ischemia-reperfusion (IR) injury compared with either alone. Adult male Sprague Dawley rats (n = 50) were equally divided into sham control (SC), IR, IR-Ex4 (10 μg/kg subcutaneously 30 min after reperfusion and daily for 5 days), IR-Mel (20 mg/kg intraperitoneally at 30 min postreperfusion and 50 mg/kg at 6 and 18 hr), and IR-Ex4-Mel were euthanized at day 14. Serum creatinine level and urine protein-to-creatinine ratio at days 3 and 14 were highest in IR group and lowest in SC, significantly higher in IR-Ex4 and IR-Mel groups than in IR-Ex4-Mel group (all P < 0.001) without significant difference between IR-Ex4 and IR-Mel groups. Changes in podocyte injury score (PIS) and kidney injury score were highest in IR group and lowest in SC, significantly higher in IR-Ex4 and IR-Mel groups than in IR-Ex4-Mel, and significantly higher in IR-Mel group than in IR-Ex4 group (all P < 0.001). Immunohistochemical microscopic findings of the expressions of FSP-1 and WT-1 (two glomerular damage indicators) and KIM-1 and snail (two renal tubular-damaged indicators) showed an identical pattern, whereas the expressions of ZO-1, p-cadherin, podocin, dystroglycan, fibronectin, and synaptopodin (six indices of glomerular integrity) demonstrated an opposite pattern compared to that of PIS among five groups (all P < 0.001). Protein expressions of inflammatory (TNF-α/NF-κB/MMP-9) and oxidative stress (NOX-1, NOX-2, oxidized protein) biomarkers exhibited an identical pattern to that of PIS among five groups (all P < 0.001). Combined melatonin-exednin-4 therapy further protected glomerulus from IR injury.

The Effect of Autophagy on Inflammation Cytokines in Renal Ischemia/Reperfusion Injury.

Acute kidney injury (AKI) is characterized by a rapid loss of kidney function and an antigen-independent inflammatory process that causes tissue damage, which was one of the main manifestations of kidney ischemia/reperfusion (I/R). Recent studies have demonstrated autophagy participated in the pathological process of acute kidney injury. In this study, we discuss how autophagy regulated inflammation response in the kidney I/R. AKI was performed by renal I/R. Autophagy activator rapamycin (Rap) and inhibitor 3-methyladenine (MA) were used to investigate the role of autophagy on kidney function and inflammation response. After the experiment, kidney tissues were obtained for the detection of autophagy-related protein microtubule-associated protein light chain 3(LC3)II, Beclin1, and Rab7 and lysosome-associated membrane protein type (LAMP)2 protein by reverse transcription-polymerase chain reaction (PT-PCR) and Western blotting, and histopathology and tissue injury scores also. The blood was harvested to measure kidney function (creatinine (Cr) and blood urea nitrogen (BUN) levels) after I/R. Cytokines TNF-α, IL-6, HMGB1, and IL-10 were measured after I/R. I/R induced the expression of LC3II, Beclin1, LAMP2, and Rab7. The activation and inhibition of autophagy by rapamycin and 3-MA were promoted and attenuated histological and renal function in renal I/R rats, respectively. Cytokines TNF-α, IL-6, and HMGB1 were decreased, and IL-10 was further increased after activation of autophagy treated in I/R rats, while 3-MA exacerbated the pro-inflammatory cytokines TNF-α, IL-6, HMGB1, and anti-inflammatory cytokine IL-10 in renal I/R. I/R can activated the autophagy, and autophagy increase mitigated the renal injury by decreasing kidney injury score, levels of Cr and BUN after renal I/R, and inflammation response via regulating the balance of pro-inflammation and anti-inflammation cytokines.

Neutrophil gelatinase-associated lipocalin attenuates injury in the rat cecal ligation and puncture model of sepsis via apoptosis inhibition.

The aim of this study was to investigate the effect of neutrophil gelatinase-associated lipocalin (NGAL) on the rat cecal ligation and puncture (CLP)-induced sepsis and the possible mechanism. Thirty male Sprague-Dawley rats underwent CLP as sepsis models and were randomized into three groups including the sham-operated group (sham, n = 10), which only underwent a laparotomy; the sepsis group (sepsis, n = 10), which underwent CLP and subcutaneous injection of normal saline; and the sepsis + NGAL group (sepsis + NGAL, n = 10), which underwent CLP and subcutaneous injection of NGAL. Urine, blood and kidney tissue samples were collected for the determination of urine NGAL (uNGAL), plasma NGAL (pNGAL), serum creatinine (Scr), blood urea nitrogen (BUN), histomorphological and immunohistochemical examination, lipid peroxidation product malondialdehyde (MDA) and superoxide dismutase (SOD), and expression of heme oxygenase-1 (HO)-1. The levels of uNGAL, pNGAL, Scr, BUN, kidney injury score, positive TUNEL staining, activated Caspase-3 and Bax, and kidney tissue MDA levels in the sepsis group were significantly increased compared with those in the sham-operated group and the sepsis + NGAL group (P < 0.05). SOD level and HO-1 expression in sepsis + NGAL group were significantly higher than those in the sham-operated group and the sepsis group (P < 0.05). NGAL can attenuate kidney injury and apoptosis in the rat CLP model of sepsis. And the protective effect of NGAL was probably due to the inhibition of apoptosis and lipid peroxidation, and increased expression of HO-1.

Endothelial Progenitor Cells Derived From Wharton's Jelly of Human Umbilical Cord Attenuate Ischemic Acute Kidney Injury by Increasing Vascularization and Decreasing Apoptosis, Inflammation, and Fibrosis.

Ischemia-reperfusion (I/R) injury to the kidney, a major cause of acute renal failure in humans, is associated with a high mortality, and the development of a new therapeutic strategy is therefore highly desirable. In this study, we examined the therapeutic potential of implantation of endothelial progenitor cells (EPCs) isolated from Wharton's jelly of human umbilical cords in the treatment of renal I/R injury in mice. To visualize the localization of the transplanted EPCs, the cells were labeled with Q-tracker before injection into the renal capsule. Mice with renal I/R injury showed a significant increase in blood urea nitrogen and creatinine levels, and these effects were decreased by EPC transplantation. The kidney injury score in the mice with I/R injury was also significantly decreased by EPC transplantation. EPC transplantation increased the microvascular density, and some of the EPCs surrounded and were incorporated into microvessels. In addition, EPC transplantation inhibited the I/R-induced cell apoptosis of endothelial, glomerular, and renal tubular cells, as demonstrated by TUNEL staining, and significantly reduced reactive oxygen species production and the expression of the inflammatory chemokines macrophage inflammatory protein-2 and keratinocyte-derived cytokine, as shown by immunostaining and ELISA. Moreover, EPC transplantation reduced I/R-induced fibrosis, as demonstrated by immunostaining for S100A4, a fibroblast marker, and by Jones silver staining. To our knowledge, this is the first report that transplantation of EPCs from Wharton's jelly of human umbilical cords might provide a novel therapy for ischemic acute kidney injury by promoting angiogenesis and inhibiting apoptosis, inflammation, and fibrosis.

Hydrogen sulfide improves resuscitation via non-hibernatory mechanisms in a porcine shock model

BackgroundHydrogen sulfide (H2S) has been demonstrated to induce a “suspended animation-like” state in rodent models by reversible inhibition of cellular respiration and marked metabolic suppression and has been proposed as a potential pharmacologic adjunct to resuscitation from shock states. There are few data currently available about the mechanisms and efficacy of H2S in larger animals or humans. We examined H2S as a pharmacologic adjunct to resuscitation in a porcine model of severe traumatic shock. MethodsTwenty-one adult swine were assigned to three study arms: sham, H2S, and saline vehicle controls (SC). All pigs underwent laparotomy and instrumentation, and the two study arms then underwent a 35% controlled hemorrhage followed by 50 min of truncal ischemia via aortic cross-clamp. H2S (5 mg/kg) or saline was administered immediately before reperfusion, followed by 6 h of resuscitation. Resuscitation requirements, laboratory parameters, end-organ histology, and inflammatory product gene expression (by reverse transcription–polymerase chain reaction) were measured and compared between groups. ResultsAll animals survived to the 6-h postresuscitation time point. Both treatment arms demonstrated severe shock characterized by fluid and vasopressor requirements, metabolic acidosis, and hypotension compared with sham animals. Animals treated with H2S demonstrated significantly lower resuscitative requirements (total epinephrine 727 versus 3052 μg; P < 0.05), decreased fluid requirements, and lower serum lactate levels (7 versus 10 mmol/L) versus SC. Cardiac output was slightly decreased with H2S treatment but all other hemodynamic and metabolic parameters were equivalent between H2S and C groups. Serum liver and kidney biomarkers were unchanged, but administration of H2S was associated with a significant improvement in histopathologic liver and kidney injury scores compared with SC (both P < 0.05). Both study groups demonstrated significantly increased gene expression of hypoxia-inducible factor 1α and nitric oxide synthase (endogenous nitric oxide synthase, inducible nitric oxide synthase [iNOS]2, iNOS3) relative to sham animals. However, H2S was associated with increased expression of hypoxia-inducible factor 1α and decreased iNOS2 levels compared with SC. ConclusionsAdministration of H2S in a large-animal model of severe traumatic shock resulted in a significant decrease in resuscitative requirements, decreased metabolic acidosis, and less end-organ histologic injury compared with standard resuscitation. H2S did not induce profound metabolic suppression as seen in rodents, and appears to have alternative mechanisms of action in large animals.

Impact of kidney injury on fluid overload and impaired oxygenation

Severity of acute kidney injury (AKI) and fluid overload (FO) are not incorporated into current severity of illness measures and are invisible to the practitioner. The causal relationship and timing between AKI and FO and oxygenation is not clear. The Fluid Overload Kidney Injury Score (FOKIS) is a daily score incorporating subscores for AKI (pRIFLE (creatinine (Cr) and urine output (UOP))), FO (total fluid (in - out) / ICU admission weight) >15% in five percentile increments, and exposure to nephrotoxic medications. We previously reported that FOKIS outperforms PRISM in mortality prediction in our pediatric intensive care unit (PICU). We hypothesized that patients with AKI on admission to the PICU developed worse fluid overload and in turn worse oxygenation.

Sitagliptin protects rat kidneys from acute ischemia-reperfusion injury via upregulation of GLP-1 and GLP-1 receptors.

Sitagliptin, an oral glucose-lowering agent, has been found to produce cardiovascular protection possibly via anti-inflammatory and anti-atherosclerotic activities of glucagon-like peptide-1 receptor (GLP-1). The aim of this study was to investigate whether sitagliptin protected the kidney function from acute ischemia-reperfusion (IR) injury in rats. Adult male SD rats were categorized into 4 groups: sham control, IR injury, IR+sitagliptin (300 mg/kg) and IR+sitagliptin (600 mg/kg). Acute renal IR injury of both kidneys was induced by clamping the renal pedicles for 1 h. The drug was orally administered at 1, 24 and 48 h after acute IR. Blood samples and 24-h urine were collected before and at 72 h after acute IR. Then the rats were sacrificed, and the kidneys were harvested for biochemical and immunohistochemical studies. Acute IR procedure markedly increased serum levels of creatinine and BUN and the ratio of urine protein to creatinine. The kidney injury score, inflammatory biomarkers (MMP-9, TNF-α and NF-κB) levels and CD68+ cells in IR kidneys were considerably increased. The expression of oxidized protein, reactive oxygen species (NOX-1, NOX-2) and apoptosis proteins (Bax, caspase-3, PARP) in IR kidneys was also significantly upregulated. All these pathological changes were suppressed by sitagliptin in a dose-dependent manner. Furthermore, the serum GLP-1 level, and the expression of GLP-1 receptor, anti-oxidant biomarkers (HO-1 and NQO-1 cells, as well as SOD-1, NQO-1 and HO-1 proteins), and angiogenesis markers (SDF-1α+ and CXCR4+ cells) in IR kidneys were significantly increased, and further upregulated by sitagliptin. Sitagliptin dose-dependently protects rat kidneys from acute IR injury via upregulation of serum GLP-1 and GLP-1 receptor expression in kidneys.

Haptoglobin Therapy Prevents Kidney Injury in Stored Blood Resuscitation of Murine Hemorrhagic Shock

Introduction: Extracellular hemoglobin (Hb) and free heme are major breakdown products of hemolyzing Red Blood Cells (RBC). Mammals have evolved scavenger systems to bind circulating Hb with haptoglobin (Hp) and free heme with hemopexin (Hx).During storage RBC undergo numerous morphological and biochemical changes. Transfusion of stored RBC (SRBC) increases plasma levels of heme and Hb. Increased plasma Hb levels are associated with kidney injury (KI). In prolonged hemorrhagic shock (HS) systemic hypotension and hypoperfusion impair kidney function. KI is an important complication of HS and is associated with a markedly increased mortality and morbidity rate.In this study we employed a murine model of 14-day blood storage mimicking 42-day human blood storage. We first determined that HS-induced KI is more severe in mice resuscitated with SRBC than in those transfused fresh RBC (FRBC). Then we studied whether treatment with either Hp or Hx during transfusion reduced KI after SRBC-resuscitation from HS.Methods: Leukoreduced, packed RBC obtained from WT C57BL6 mice were stored in CPDA-1 at 4°C for either <24 h (FRBC) or 2 weeks (SRBC). Anesthetized mice were bled approximately 50-60% of circulating blood volume over 10 min to maintain a constant mean arterial pressure of 35 mmHg and induce HS. After 120 min of HS, mice were resuscitated with either FRBC or SRBC. Sham operated mice that did not undergo hemorrhagic shock or resuscitation served as a control group. Furthermore, some mice receiving SRBC were given a co-infusion of 7.5 mg of either Hp, or Hx or albumin (Alb) during transfusion. The Alb treated group of mice served as a control for the treatment protein loading. After recovery from anesthesia, urine was collected for 24 h in a metabolic chamber. Urine creatinine, hemoglobin, and Kidney Injury Molecule-1 (KIM-1) were measured. At 48 h post HS the mice were sacrificed and plasma markers of liver and kidney injury were measured. Kidney injury was quantified by a kidney pathology scoring system.Results: After HS and resuscitation hemoglobinuria was detected in 24 h urine samples collected from mice resuscitated with SRBC (see Table). Urine KIM-1 levels were increased after HS and resuscitation with either FRBC or SRBC (FRBC differs vs. Sham, p<0.01; SRBC differs vs. Sham, p<0.05). Plasma NGAL-levels and the kidney tubular injury score were greater in SRBC-transfused mice than in Sham operated mice or FRBC-resuscitated mice (KI score: SRBC differs vs. Sham and FRBC, p<0.01). Hemoglobinuria was present in SRBC-resuscitated mice treated with Alb or Hx but not SRBC transfused mice treated with Hp. Plasma NGAL levels at 48 h after shock did not differ in mice resuscitated with SRBC+Hp or FRBC but were greater in mice resuscitated with SRBC+Alb and SRBC+Hx. Plasma Hb levels at 48 h after resuscitation were less than 33.1±6.4 mg/ml and did not differ from Sham levels between all groups, but plasma Hb levels were 7-fold increased to 231.7±25.7 mg/ml in mice transfused with SRBC+Hp (SRBC+Hp differs vs. all other groups; p<0.001). Plasma levels of alanine aminotransferase (ALT) and aspartate aminotransferase (AST) were greater after resuscitation with SRBC and with all three treatments than after resuscitation with FRBC.Conclusion: In comparison to resuscitation from HS with FRBC, resuscitation with SRBC produced hemoglobinuria and greater KI. Treatment with exogenous Hp during transfusion but not treatment with Hx or Alb reduced SRBC-induced hemoglobinuria and prevented kidney injury after HS and resuscitation with SRBC. Treatment with exogenous Hp may prevent KI associated with high plasma Hb concentrations such as after massive transfusion of stored blood, prolonged cardiopulmonary bypass or in acute exacerbations of hemolytic disease. [Display omitted] DisclosuresNo relevant conflicts of interest to declare.

Post-Transplant Glomerulonephritis Has a Molecular Behavior of Antibody Mediated Rejection.

Post-transplant glomerulonephritis (GN) is a common cause of kidney transplant failure. We studied conventional and molecular features in 69 biopsies diagnosed as GN from 62 patients, identified in prospective studies of 703 unselected indication biopsies from 562 kidney transplants. We grouped these biopsies as 19 IgAN, seven FSGS, four MGN, seven MPGN, 10 proliferative GN, and 22 that were not considered classifiable by the pathologist. Using the microarray-based molecular microscope system, we studied transcript sets and molecular scores, particularly the Acute Kidney Injury (AKI) Score and the Antibody-Mediated Rejection (ABMR) Score. GN biopsies had molecular abnormalities, generally intermediate between ABMR and normal transplants, and were not related to the GN type. In biopsies with GN, the AKI and ABMR Scores in multivariable analysis were independent predictors of failure, and both correlated with histologic scarring and reduced GFR. High ABMR Scores in GN also correlated with cg and g lesions. Positive ABMR Scores in some biopsies with a histologic diagnosis of GN could reflect two diseases (ABMR plus GN), ABMR-like mechanisms in some GN, or mistaken diagnosis of GN in ABMR. GN biopsies with high ABMR score had a worse graft survival than the others.Figure: No Caption available.The strong association of molecular scores such as the AKI Score with outcomes in post transplant GN provides new prognostic insight, and suggests potential for application of molecular methods in primary GN. DISCLOSURE:Halloran, P.: Speaker’s Bureau, Astellas, Novartis, OneLamba.

Critical blood pressure threshold dependence of hypertensive injury and repair in a malignant nephrosclerosis model.

Most patients with essential hypertension do not exhibit substantial renal damage. Renal autoregulation by preventing glomerular transmission of systemic pressures has been postulated to mediate this resistance. Conversely, malignant nephrosclerosis (MN) has been postulated to develop when severe hypertension exceeds a critical ceiling. If the concept is valid, even modest blood pressure (BP) reductions to below this threshold regardless of antihypertensive class (1) should prevent MN and (2) lead to the healing of the already developed MN lesions. Both predicates were tested using BP radiotelemetry in the stroke-prone spontaneously hypertensive rats receiving 1% NaCl as drinking fluid for 4 weeks. Severe hypertension (final 2 weeks average systolic BP, >200 mm Hg) and MN (histological damage score 36±5; n=27) developed in the untreated stroke-prone spontaneously hypertensive rats but were prevented by all antihypertensive classes (enalapril [n=15], amlodipine [n=13], or a hydralazine/hydrochlorothiazide combination [n=15]) if the final 2-week systolic BP remained <190 mm Hg. More impressively, modest systolic BP reductions to 160 to 180 mm Hg (hydralazine/hydrochlorothiazide regimen) initiated at ≈4 weeks in additional untreated rats after MN had already developed (injury score 35±4 in the right kidney removed before therapy) led to a striking resolution of the vascular and glomerular MN injury over 2 to 3 weeks (post-therapy left kidney injury score 9±2, P<0.0001; n=27). Proteinuria also declined rapidly from 122±9.5 mg/24 hours before therapy to 20.5±3.6 mg 1 week later. These data clearly demonstrate the barotrauma-mediated pathogenesis of MN and the striking capacity for spontaneous and rapid repair of hypertensive kidney damage if new injury is prevented.