Sarah Faubel

University of Colorado, Denver, Colorado, United States

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Publications (55)259.09 Total impact

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    ABSTRACT: Caspase-1, IL-1α, and IL-1β are known to be activated in the NLRP3 inflammasome. The inflammasome is activated mostly in inflammatory cells. The presence of inflammasome proteins in proximal tubules (PTs) and the effect of cisplatin-treatment or caspase inhibition on inflammasome proteins in PTs are not known. The aim of this study was to investigate the effect of cisplatin on inflammasome proteins in freshly isolated PTs and also to determine the effect of caspase inhibition on inflammasome proteins and PT injury. PTs were isolated using collagenase digestion and Percoll centrifugation. After recovery period, freshly isolated PTs were incubated with vehicle, 50 µM cisplatin or 50 µM cisplatin plus 50 µM pan caspase inhibitor, QVD-OPH. PTs treated with 50 µM cisplatin showed Propidium Iodide staining indicative of necrosis. Necrotic cells (%) were 2.2 in Vehicle-treated, 37.7 in Cisplatin-treated (p < 0.05 vs. Vehicle), and 3.3 in QVD-treated (p < 0.05 vs. Cisplatin). LDH release (%), a marker of cell membrane damage seen in necrosis was 7.1 in Vehicle-treated, 39.7 in Cisplatin-treated (p < 0.05 vs. Vehicle), and 13.5 in QVD-treated (p < 0.05 vs. Cisplatin). Caspase-1 activity and active caspase-1 protein (10 kDa) were significantly increased in Cisplatin-treated PTs. NLRP3 was strongly expressed in PTs, but there were no significant changes between groups. Pro-apoptotic BID (22 kDa) was unchanged between groups. IL-1α and IL-1β activity was increased in Cisplatin-treated PTs. QVD-OPH co-treatment decreased caspase-1, IL-1α, and IL-1β. In summary, caspase inhibition decreases caspase-1, IL-1α, and IL-1β but not NLRP3 or BID protein and protects against necrosis in cisplatin-treated freshly isolated PTs.
    Renal Failure 10/2014; · 0.94 Impact Factor
  • Kenneth W Hung, Judith Blaine, Sarah Faubel
    JAMA Internal Medicine 08/2014; · 13.25 Impact Factor
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    ABSTRACT: Patients with acute kidney injury (AKI) have increased mortality; data suggest that the duration, not just severity, of AKI predicts increased mortality. Animal models suggest that AKI is a multisystem disease that deleteriously affects the lungs, heart, brain, intestine, and liver; notably, these effects have only been examined within 48 h, and longer term effects are unknown. In this study, we examined the longer term systemic effects of AKI, with a focus on lung injury. Mice were studied 7 days after an episode of ischemic AKI (22 min of renal pedicle clamping and then reperfusion) and numerous derangements were present including (1) lung inflammation; (2) increased serum proinflammatory cytokines; (3) liver injury; and (4) increased muscle catabolism. Since fluid overload may cause respiratory complications post-AKI and fluid management is a critical component of post-AKI care, we investigated various fluid administration strategies in the development of lung inflammation post-AKI. Four different fluid strategies were tested – 100, 500, 1000, or 2000 μL of saline administered subcutaneously daily for 7 days. Interestingly, at 7 days post-AKI, the 1000 and 2000 μL fluid groups had less severe AKI and less severe lung inflammation versus the 100 and 500 μL groups. In summary, our data demonstrate that appropriate fluid management after an episode of ischemic AKI led to both (1) faster recovery of kidney function and (2) significantly reduced lung inflammation, consistent with the notion that interventions to shorten AKI duration have the potential to reduce complications and improve patient outcomes.
    Physiological Reports. 07/2014; 2(7).
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    ABSTRACT: World Kidney Day 2013 focused on raising awareness of the impact and consequences of acute kidney injury (AKI). Although many studies have examined rates of AKI in hospitalized patients, we were interested in the impact of AKI on the workload of nephrologists. Cross-sectional forced-choice internet-based survey. 598 survey respondents who were US-based nephrologist members of the American Society of Nephrology. Numbers of inpatients and outpatients seen on World Kidney Day 2013 for the management of AKI or other conditions (and specifically in-hospital renal replacement therapies [RRTs]), based on self-report of number/percentage of patients seen on World Kidney Day and in the prior year. Of 598 physician respondents (response rate, 12%), 310 saw patients in the hospital on World Kidney Day. Of 3,285 patients seen by respondents, 1,500 were seen for AKI (46%); 1,233, for end-stage renal disease (37%); and 552, for non-AKI/end-stage renal disease-related problems (17%). Of patients with AKI, 688 (46%) were in the intensive care unit and 415 (28%) received RRT. Intermittent hemodialysis was performed in 315 patients (76%) who received RRT. Delivered dialysis dose was quantified in only 48 (15%) of those receiving intermittent hemodialysis. 260 respondents saw 2,380 patients in the ambulatory setting, of whom 207 (9%) were seen for follow-up of AKI. There was a low response rate to the survey. Numbers of patients were self-reported. This is the first physician survey examining the care of patients and impact of AKI on current in-hospital and ambulatory nephrology practices. In our sample, AKI was the most common reason for in-hospital nephrology consultation. Furthermore, our findings point to significant areas in which improvement is needed, including inadequate quantification of dialysis delivered dose. Finally, our survey highlights that AKI is a major public health issue.
    American Journal of Kidney Diseases 05/2014; · 5.29 Impact Factor
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    ABSTRACT: Background World Kidney Day 2013 focused on raising awareness of the impact and consequences of acute kidney injury (AKI). Although many studies have examined rates of AKI in hospitalized patients, we were interested in the impact of AKI on the workload of nephrologists. Study Design Cross-sectional forced-choice internet-based survey. Setting & Participants 598 survey respondents who were US-based nephrologist members of the American Society of Nephrology. Outcomes Numbers of inpatients and outpatients seen on World Kidney Day 2013 for the management of AKI or other conditions (and specifically in-hospital renal replacement therapies [RRTs]), based on self-report of number/percentage of patients seen on World Kidney Day and in the prior year. Results Of 598 physician respondents (response rate, 12%), 310 saw patients in the hospital on World Kidney Day. Of 3,285 patients seen by respondents, 1,500 were seen for AKI (46%); 1,233, for end-stage renal disease (37%); and 552, for non−AKI/end-stage renal disease–related problems (17%). Of patients with AKI, 688 (46%) were in the intensive care unit and 415 (28%) received RRT. Intermittent hemodialysis was performed in 315 patients (76%) who received RRT. Delivered dialysis dose was quantified in only 48 (15%) of those receiving intermittent hemodialysis. 260 respondents saw 2,380 patients in the ambulatory setting, of whom 207 (9%) were seen for follow-up of AKI. Limitations There was a low response rate to the survey. Numbers of patients were self-reported. Conclusions This is the first physician survey examining the care of patients and impact of AKI on current in-hospital and ambulatory nephrology practices. In our sample, AKI was the most common reason for in-hospital nephrology consultation. Furthermore, our findings point to significant areas in which improvement is needed, including inadequate quantification of dialysis delivered dose. Finally, our survey highlights that AKI is a major public health issue.
    American Journal of Kidney Diseases 01/2014; · 5.29 Impact Factor
  • Sarah Faubel
    American Journal of Kidney Diseases 12/2013; 62(6):1030-1033. · 5.29 Impact Factor
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    ABSTRACT: As judged by the American College of Radiology Appropriateness Criteria, renal Doppler ultrasonography is the most appropriate imaging test in the evaluation of AKI and has the highest level of recommendation. Unfortunately, nephrologists are rarely specifically trained in ultrasonography technique and interpretation, and important clinical information obtained from renal ultrasonography may not be appreciated. In this review, the strengths and limitations of grayscale ultrasonography in the evaluation of patients with AKI will be discussed with attention to its use for (1) assessment of intrinsic causes of AKI, (2) distinguishing acute from chronic kidney diseases, and (3) detection of obstruction. The use of Doppler imaging and the resistive index in patients with AKI will be reviewed with attention to its use for (1) predicting the development of AKI, (2) predicting the prognosis of AKI, and (3) distinguishing prerenal azotemia from intrinsic AKI. Finally, pediatric considerations in the use of ultrasonography in AKI will be reviewed.
    Clinical Journal of the American Society of Nephrology 11/2013; · 5.07 Impact Factor
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    ABSTRACT: Heparanase, a heparan sulfate-specific glucuronidase, mediates the onset of pulmonary neutrophil adhesion and inflammatory lung injury during early sepsis. We hypothesized that glomerular heparanase is similarly activated during sepsis and contributes to septic acute kidney injury (AKI). We induced polymicrobial sepsis in mice using cecal ligation and puncture (CLP) in the presence or absence of competitive heparanase inhibitors (heparin or nonanticoagulant N-desulfated re-N-acetylated heparin [NAH]). Four hours after surgery, we collected serum and urine for measurement of renal function and systemic inflammation, invasively determined systemic hemodynamics, harvested kidneys for histology/protein/mRNA, and/or measured glomerular filtration by inulin clearance. CLP-treated mice demonstrated early activation of glomerular heparanase with coincident loss of glomerular filtration, as indicated by a >twofold increase in blood urea nitrogen (BUN) and a >50% decrease in inulin clearance (P < 0.05) in comparison to sham mice. Administration of heparanase inhibitors 2 h prior to CLP attenuated sepsis-induced loss of glomerular filtration rate, demonstrating that heparanase activation contributes to early septic renal dysfunction. Glomerular heparanase activation was not associated with renal neutrophil influx or altered vascular permeability, in marked contrast to previously described effects of pulmonary heparanase on neutrophilic lung injury during sepsis. CLP induction of renal inflammatory gene (IL-6, TNF-α, IL-1β) expression was attenuated by NAH pretreatment. While serum inflammatory indices (KC, IL-6, TNF-α, IL-1β) were not impacted by NAH pretreatment, heparanase inhibition attenuated the CLP-induced increase in serum IL-10. These findings demonstrate that glomerular heparanase is active during sepsis and contributes to septic renal dysfunction via mechanisms disparate from heparanase-mediated lung injury.
    Physiological reports. 11/2013; 1(6):e00153.
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    ABSTRACT: The incidence rate of AKI is increasing across the spectrum of hospitalized children and adults. Given the increased morbidity and mortality associated with AKI, significant research effort has been appropriately focused on standardizing AKI definitions, identifying risk factors, and discovering and validating novel, earlier structural biomarkers of kidney injury. In addition, a growing body of evidence demonstrates that AKI is a risk factor for the future development or accelerated progression of CKD. Unfortunately, prospective observational studies have not consistently followed survivors of episodes of AKI for longitudinal outcomes after hospital discharge, which could lead to ascertainment bias in terms of over- or underestimation of CKD development. Furthermore, data show that clinical follow-up of AKI survivors is low. This lack of systematic study and clinical follow-up represents a potential missed opportunity to prevent chronic disease after an acute illness and improve outcomes. Therefore, prospective study of transitions of care after episodes of AKI is needed to identify which patients are at risk for CKD development and to optimally target therapeutic interventions.
    Clinical Journal of the American Society of Nephrology 03/2013; 8(3):476-83. · 5.07 Impact Factor
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    ABSTRACT: BACKGROUND: AKI is common following liver transplantation and is associated with significant morbidity and mortality. Biomarkers of AKI have not been well established in this setting but are needed to help guide patient care and facilitate development of novel therapeutics. METHODS: Serum creatinine, cystatin C, IL-6, and IL-8 and urine IL-18, NGAL, IL-6, and IL-8 were measured before and within 24 hours after liver transplantation in 40 patients. AKI was defined as a >=50% sustained increase in creatinine above pre-operative values occurring within 24 hours of transplantation and persisting for at least 24 hours. RESULTS: Seven patients met criteria for AKI (17.5%), with mean creatinines of 0.81 mg/dL pre-operatively and 1.75 mg/dL post-operatively. While pre-operative biomarker levels in patients with AKI were similar to those in patients without AKI, differences were seen between the groups with regard to median post-operative serum IL-8 (pg/mL) (242.48 vs. 82.37, p = 0.0463) and urine NGAL (ng/mL) (386.86 vs. 24.31, p = 0.0039), IL-6 (pg/mL) (52 vs. 7.29, p=0.0532), IL-8 (pg/mL) (14.3 vs. 0, p = 0.0224), and IL-18 (pg/mL) (883.09 vs. 0, p = 0.0449). The areas under receiver operating characteristic (ROC) curves were 0.749 for urine IL-18, 0.833 for urine NGAL, 0.745 for urine IL-6, 0.682 for serum IL-6, 0.773 for urine IL-8, and 0.742 for serum IL-8. Post-operative cystatin C was not significantly different between AKI and no AKI groups. CONCLUSION: Serum IL-8 and urine IL-18, NGAL, IL-6, and IL-8 are elevated in AKI within the first 24 hours following liver transplantation.
    BMC Nephrology 01/2013; 14(1):17. · 1.64 Impact Factor
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    ABSTRACT: Acute kidney injury (AKI) and acute lung injury (ALI) are serious complications of sepsis. AKI is often viewed as a late complication of sepsis. Notably, the onset of AKI relative to ALI is unclear as routine measures of kidney function (BUN and creatinine) are insensitive and increase late. In this study, we hypothesized that AKI and ALI would occur simultaneously due to a shared pathophysiology (i.e., TNF-α mediated systemic inflammatory response syndrome [SIRS]), but that sensitive markers of kidney function would be required to identify AKI. Sepsis was induced in adult male C57B/6 mice with 5 different one time doses of intraperitoneal (IP) endotoxin (LPS) (0.00001, 0.0001, 0.001, 0.01, or 0.25 mg) or cecal ligation and puncture (CLP). SIRS was assessed by serum proinflammatory cytokines (TNF-α, IL-1β, CXCL1, IL-6), ALI was assessed by lung inflammation (lung myeloperoxidase [MPO] activity), and AKI was assessed by serum creatinine, BUN, and glomerular filtration rate (GFR) (by FITC-labeled inulin clearance) at 4 hours. 20 µgs of TNF-α antibody (Ab) or vehicle were injected IP 2 hours before or 2 hours after IP LPS. Serum cytokines increased with all 5 doses of LPS; AKI and ALI were detected within 4 hours of IP LPS or CLP, using sensitive markers of GFR and lung inflammation, respectively. Notably, creatinine did not increase with any dose; BUN increased with 0.01 and 0.25 mg. Remarkably, GFR was reduced 50% in the 0.001 mg LPS dose, demonstrating that dramatic loss of kidney function can occur in sepsis without a change in BUN or creatinine. Prophylactic TNF-α Ab reduced serum cytokines, lung MPO activity, and BUN; however, post-sepsis administration had no effect. ALI and AKI occur together early in the course of sepsis and TNF-α plays a role in the early pathogenesis of both.
    PLoS ONE 01/2013; 8(11):e79037. · 3.53 Impact Factor
  • Sarah Faubel
    American Journal of Kidney Diseases 01/2013; 62(6):1030–1033. · 5.29 Impact Factor
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    ABSTRACT: The presence of albuminuria is strongly associated with progression of chronic kidney disease. While albuminuria has been shown to injure renal proximal tubular cells, the effects of albumin on podocytes have been less well studied. We have addressed the hypothesis that exposure of podocytes to albumin initiates an injury response. We studied transformed human-urine derived podocytes-like epithelial cells (HUPECS, or podocytes). Upon differentiation, these cells retain certain characteristics of differentiated podocytes, including expression of synaptopodin, CD2AP, and nestin. We exposed podocytes to recombinant human albumin, which lacks lipids and proteins that bind serum albumin; this reagent allowed a direct examination of the effects of albumin. Podocytes endocytosed fluoresceinated albumin and this process was inhibited at 4°C, suggesting an energy-dependent process. Exposure to albumin at concentrations of 5 and 10 mg/ml was associated with increased cell death in a dose-dependent manner. The mechanism of cell death may involve apoptosis, as caspase 3/7 were activated and the pan-caspase inhibitor z-VAD reduced cell death. Albumin exposure also increased nuclear factor (NF)-κB activation and increased transcription and release of interleukin (IL-) 1β, tumor necrosis factor (TNF), and IL-6. We extended these findings to an in vivo model. Glomeruli isolated from mice with nephrotic syndrome also had increased expression of IL-1β and TNF RNA. These data suggest that while podocyte injury begets albuminuria, albumin in the glomerular ultrafiltrate may also beget podocyte injury. Thus, an additional mechanism by which anti-proteinuric therapies are beneficial in the treatment of glomerular diseases may be a reduction in injury to the podocyte by albumin.
    PLoS ONE 01/2013; 8(1):e54817. · 3.53 Impact Factor
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    ABSTRACT: Serum and bronchoalveolar fluid IL-6 are increased in patients with acute respiratory distress syndrome (ARDS) and predict prolonged mechanical ventilation and poor outcomes, although the role of intra-alveolar IL-6 in indirect lung injury is unknown. We investigated the role of endogenous and exogenous intra-alveolar IL-6 in AKI-mediated lung injury (indirect lung injury), intraperitoneal (IP) endotoxin administration (indirect lung injury) and, for comparison, intratracheal (IT) endotoxin administration (direct lung injury) with the hypothesis that IL-6 would exert a pro-inflammatory effect in these causes of acute lung inflammation. Bronchoalveolar cytokines (IL-6, CXCL1, TNF-α, IL-1β, and IL-10), BAL fluid neutrophils, lung inflammation (lung cytokines, MPO activity [a biochemical marker of neutrophil infiltration]), and serum cytokines were determined in adult male C57Bl/6 mice with no intervention or 4 hours after ischemic AKI (22 minutes of renal pedicle clamping), IP endotoxin (10 µg), or IT endotoxin (80 µg) with and without intratracheal (IT) IL-6 (25 ng or 200 ng) treatment. Lung inflammation was similar after AKI, IP endotoxin, and IT endotoxin. BAL fluid IL-6 was markedly increased after IT endotoxin, and not increased after AKI or IP endotoxin. Unexpectedly, IT IL-6 exerted an anti-inflammatory effect in healthy mice characterized by reduced BAL fluid cytokines. IT IL-6 also exerted an anti-inflammatory effect in IT endotoxin characterized by reduced BAL fluid cytokines and lung inflammation; IT IL-6 had no effect on lung inflammation in AKI or IP endotoxin. IL-6 exerts an anti-inflammatory effect in direct lung injury from IT endotoxin, yet has no role in the pathogenesis or treatment of indirect lung injury from AKI or IP endotoxin. Since intra-alveolar inflammation is important in the pathogenesis of direct, but not indirect, causes of lung inflammation, IT anti-inflammatory treatments may have a role in direct, but not indirect, causes of ARDS.
    PLoS ONE 01/2013; 8(5):e61405. · 3.53 Impact Factor
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    ABSTRACT: Serum IL-6 is increased in patients with acute kidney injury (AKI) and is associated with prolonged mechanical ventilation and increased mortality. Inhibition of IL-6 in mice with AKI reduces lung injury associated with a reduction in the chemokine CXCL1 and lung neutrophils. Whether circulating IL-6 or locally produced lung IL-6 mediates lung injury after AKI is unknown. We hypothesized that circulating IL-6 mediates lung injury after AKI by increasing lung endothelial CXCL1 production and subsequent neutrophil infiltration. To test the role of circulating IL-6 in AKI-mediated lung injury, recombinant murine IL-6 was administered to IL-6-deficient mice. To test the role of CXCL1 in AKI-mediated lung injury, CXCL1 was inhibited by use of CXCR2-deficient mice and anti-CXCL1 antibodies in mice with ischemic AKI or bilateral nephrectomy. Injection of recombinant IL-6 to IL-6-deficient mice with AKI increased lung CXCL1 and lung neutrophils. Lung endothelial CXCL1 was increased after AKI. CXCR2-deficient and CXCL1 antibody-treated mice with ischemic AKI or bilateral nephrectomy had reduced lung neutrophil content. In summary, we demonstrate for the first time that circulating IL-6 is a mediator of lung inflammation and injury after AKI. Since serum IL-6 is increased in patients with either AKI or acute lung injury and predicts prolonged mechanical ventilation and increased mortality in both conditions, our data suggest that serum IL-6 is not simply a biomarker of poor outcomes but a pathogenic mediator of lung injury.
    AJP Renal Physiology 07/2012; 303(6):F864-72. · 4.42 Impact Factor
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    ABSTRACT: Background Serum cytokines are increased in patients with acute kidney injury (AKI) and predict increased mortality. It is widely assumed that increased renal production of cytokines is the source of increased serum cytokines; the role of extra-renal cytokine production and impaired renal cytokine clearance is less well studied. We hypothesized that cytokine production in AKI was mononuclear phagocyte dependent, independent of production by the kidneys, and that serum cytokine clearance would be impaired in AKI.Methods Bilateral nephrectomy was used as a model of AKI to assess cytokine production independent of kidney cytokine production. Mononuclear phagocytes were depleted utilizing intravenous (IV) administration of liposome-encapsulated clodronate (LEC). Twenty-three serum cytokines were determined utilizing a multiplex cytokine kit. Proteins for cytokines were determined in the spleen and liver by enzyme-linked immunosorbent assay. Recombinant cytokines were injected by IV into mice with bilateral nephrectomy to determine the effect of absent kidney function on serum cytokine clearance.ResultsSerum interleukin (IL)-6, chemokine (C-X-C motif) ligand 1 (CXCL1), IL-10, IL-1β, monocyte chemotactic protein 1 (MCP-1), IL-5 and eotaxin were increased in the serum of mice after bilateral nephrectomy and were reduced with LEC. Serum IL-12p40 and regulated upon activation, normal T-cell expressed, and secreted (RANTES) were increased after bilateral nephrectomy and were further increased with LEC. Spleen IL-6, CXCL1, IL-10 and IL-1β and liver IL-6 and IL-10 were increased after bilateral nephrectomy. After IV injection, IL-6, CXCL1, IL-10 and IL-1β had a prolonged serum cytokine appearance in mice with bilateral nephrectomy versus sham operation.Conclusions Increased mononuclear phagocyte production and impaired renal clearance contribute to serum cytokine accumulation in AKI, independent of kidney injury. The effect of AKI on cytokine production and clearance may contribute to the increased mortality of patients with AKI.
    Nephrology Dialysis Transplantation 07/2012; · 3.37 Impact Factor
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    ABSTRACT: The innate immune system causes tissue inflammation and injury after renal ischemia/reperfusion (I/R). The complement system is activated on ischemic tubular epithelial cells (TECs) and induces the cells to produce pro-inflammatory chemokines. TECs also express toll-like receptors (TLRs)-2 and -4. Signaling through the TLRs induces TECs to produce a variety of chemokines, some of which can also be induced by complement activation fragments. We sought to determine whether the effects of complement activation and TLR signaling in TECs are redundant, or whether additive protection can be achieved by blocking both of these innate immune systems. To confirm that the complement system, TLR-2 signaling, and TLR-4 signaling induce production of a similar repertoire of inflammatory chemokines, we stimulated TECs with complement sufficient serum or with TLR-2 and TLR-4 ligands in vitro. We found that all three of these stimuli induce TECs to produce KC, MIP-2, IL-6, and TNF-α, and that there was a trend toward greater production of KC in cells exposed to two stimuli. Based upon these results, we hypothesized that mice deficient in both complement activation and TLR-2 signaling would demonstrate greater protection from I/R than mice deficient only in the complement system. To test this hypothesis we induced ischemic acute kidney injury (AKI) in wild-type mice, mice with targeted deletion of complement factor B (fB(-/-) mice), or mice with targeted deletion of factor B and TLR-2 (fB(-/-)TLR2(-/-) mice). Surprisingly, we found that fB(-/-)TLR2(-/-) mice developed more severe injury than those with single deficiency of factor B. Our results indicate that blockade of the complement system may be more protective than simultaneous blockade of both the complement system and TLR-2 in ischemic AKI.
    Molecular Immunology 06/2012; 52(3-4):249-57. · 2.65 Impact Factor
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    ABSTRACT: Acute kidney injury (AKI) remains a complex clinical problem associated with significant short-term morbidity and mortality and lacking effective pharmacologic interventions. Patients with AKI experience longer-term risks for progressive chronic ESRD, which diminish patients' health-related quality of life and create a larger burden on the healthcare system. Although experimental models have yielded numerous promising agents, translation into clinical practice has been unsuccessful, possibly because of issues in clinical trial design, such as delayed drug administration, masking of therapeutic benefit by adverse events, and inadequate sample size. To address issues of clinical trial design, the National Institute of Diabetes and Digestive and Kidney Diseases sponsored a workshop titled "Clinical Trials in Acute Kidney Injury: Current Opportunities and Barriers" in December 2010. Workshop participants included representatives from academia, industry, and government agencies whose areas of expertise spanned basic science, clinical nephrology, critical care medicine, biostatistics, pharmacology, and drug development. This document summarizes the discussions of collaborative workgroups that addressed issues related to patient selection, study endpoints, the role of novel biomarkers, sample size and power calculations, and adverse events and pilot/feasibility studies in prevention and treatment of AKI. Companion articles outline the discussions of workgroups for model trials related to prevention or treatment of established AKI in different clinical settings, such as in patients with sepsis.
    Clinical Journal of the American Society of Nephrology 03/2012; 7(5):844-50. · 5.07 Impact Factor
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    ABSTRACT: AKI remains an important clinical problem, with a high mortality rate, increasing incidence, and no Food and Drug Administration-approved therapeutics. Advances in addressing this clinical need require approaches for rapid diagnosis and stratification of injury, development of therapeutic agents based on precise understanding of key pathophysiological events, and implementation of well designed clinical trials. In the near future, AKI biomarkers may facilitate trial design. To address these issues, the National Institute of Diabetes and Digestive and Kidney Diseases sponsored a meeting, "Clinical Trials in Acute Kidney Injury: Current Opportunities and Barriers," in December of 2010 that brought together academic investigators, industry partners, and representatives from the National Institutes of Health and the Food and Drug Administration. Important issues in the design of clinical trials for interventions in AKI in patients with sepsis or AKI in the setting of critical illness after surgery or trauma were discussed. The sepsis working group discussed use of severity of illness scores and focus on patients with specific etiologies to enhance homogeneity of trial participants. The group also discussed endpoints congruent with those endpoints used in critical care studies. The second workgroup emphasized difficulties in obtaining consent before admission and collaboration among interdisciplinary healthcare groups. Despite the difficult trial design issues, these clinical situations represent a clinical opportunity because of the high event rates, severity of AKI, and poor outcomes. The groups considered trial design issues and discussed advantages and disadvantages of several short- and long-term primary endpoints in these patients.
    Clinical Journal of the American Society of Nephrology 03/2012; 7(5):856-60. · 5.07 Impact Factor
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    ABSTRACT: AKI is an important clinical problem that has become increasingly more common. Mortality rates associated with AKI remain high despite advances in supportive care. Patients surviving AKI have increased long-term mortality and appear to be at increased risk of developing CKD and progressing to ESRD. No proven effective pharmacologic therapies are currently available for the prevention or treatment of AKI. Advances in addressing this unmet need will require the development of novel therapeutic agents based on precise understanding of key pathophysiological events and the implementation of well designed clinical trials. To address this need, the National Institute of Diabetes and Digestive and Kidney Diseases sponsored the "Clinical Trials in Acute Kidney Injury: Current Opportunities and Barriers" workshop in December 2010. The event brought together representatives from academia, industry, the National Institutes of Health, and the US Food and Drug Administration. We report the discussions of workgroups that developed outlines of clinical trials for the prevention of AKI in two patient populations: patients undergoing elective surgery who are at risk for or who develop AKI, and patients who are at risk for contrast-induced AKI. In both of these populations, primary prevention or secondary therapy can be delivered at an optimal time relative to kidney injury. The workgroups detailed primary and secondary endpoints for studies in these groups, and explored the use of adaptive clinical trial designs for trials of novel preventive strategies to improve outcomes of patients with AKI.
    Clinical Journal of the American Society of Nephrology 03/2012; 7(5):851-5. · 5.07 Impact Factor

Publication Stats

1k Citations
259.09 Total Impact Points

Institutions

  • 2002–2014
    • University of Colorado
      • • Division of Renal Diseases and Hypertension
      • • Department of Medicine
      Denver, Colorado, United States
  • 2013
    • University of Alabama at Birmingham
      Birmingham, Alabama, United States
  • 2012
    • Indiana University-Purdue University Indianapolis
      • Department of Medicine
      Indianapolis, IN, United States
  • 2010
    • Denver Health and Hospital Authority
      Denver, Colorado, United States
  • 2009
    • University of California, San Francisco
      San Francisco, California, United States
  • 2008
    • Texas Tech University Health Sciences Center
      • Department of Internal Medicine
      Lubbock, TX, United States
  • 2007
    • Chang Gung Memorial Hospital
      T’ai-pei, Taipei, Taiwan
  • 2004
    • University of Colorado Hospital
      • Department of Medicine
      Denver, Colorado, United States