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Item Acute Kidney Injury Results in Long-Term Diastolic Dysfunction That Is Prevented by Histone Deacetylase Inhibition(Elsevier, 2021-02-22) Soranno, Danielle E.; Kirkbride-Romeo, Lara; Wennersten, Sara A.; Ding, Kathy; Cavasin, Maria A.; Baker, Peter; Altmann, Christopher; Bagchi, Rushita A.; Haefner, Korey R.; Steinkühler, Christian; Montford, John R.; Keith, Brysen; Gist, Katja M.; McKinsey, Timothy A.; Faubel, Sarah; Pediatrics, School of MedicineGrowing epidemiological data demonstrate that acute kidney injury (AKI) is associated with long-term cardiovascular morbidity and mortality. Here, the authors present a 1-year study of cardiorenal outcomes following bilateral ischemia-reperfusion injury in male mice. These data suggest that AKI causes long-term dysfunction in the cardiac metabolome, which is associated with diastolic dysfunction and hypertension. Mice treated with the histone deacetylase inhibitor, ITF2357, had preservation of cardiac function and remained normotensive throughout the study. ITF2357 did not protect against the development of kidney fibrosis after AKI.Item Delivery of interleukin-10 via injectable hydrogels improves renal outcomes and reduces systemic inflammation following ischemic acute kidney injury in mice(American Physiological Society, 2016-08) Soranno, Danielle E.; Rodell, Christopher B.; Altmann, Christopher; Duplantis, Jane; Andres-Hernando, Ana; Burdick, Jason A.; Faubel, Sarah; Pediatrics, School of MedicineInjectable hydrogels can be used to deliver drugs in situ over a sustained period of time. We hypothesized that sustained delivery of interleukin-10 (IL-10) following acute kidney injury (AKI) would mitigate the local and systemic proinflammatory cascade induced by AKI and reduce subsequent fibrosis. Wild-type C57BL/6 mice underwent ischemia-reperfusion AKI with avertin anesthesia. Three days later, mice were treated with either hyaluronic acid injectable hydrogel with or without IL-10, or IL-10 suspended in saline, injected under the capsule of the left kidney, or hydrogel with IL-10 injected subcutaneously. Untreated AKI served as controls. Serial in vivo optical imaging tracked the location and degradation of the hydrogel over time. Kidney function was assessed serially. Animals were killed 28 days following AKI and the following were evaluated: serum IL-6, lung inflammation, urine neutrophil gelatinase-associated lipocalin, and renal histology for fibroblast activity, collagen type III deposition and fibrosis via Picrosirius Red staining and second harmonic imaging. Our model shows persistent systemic inflammation, and renal inflammation and fibrosis 28 days following AKI. The hydrogels are biocompatible and reduced serum IL-6 and renal collagen type III 28 days following AKI even when delivered without IL-10. Treatment with IL-10 reduced renal and systemic inflammation, regardless of whether the IL-10 was delivered in a sustained manner via the injectable hydrogel under the left kidney capsule, as a bolus injection via saline under the left kidney capsule, or via the injectable hydrogel subcutaneously. Injectable hydrogels are suitable for local drug delivery following renal injury, are biocompatible, and help mitigate local and systemic inflammation.Item Female and male mice have differential longterm cardiorenal outcomes following a matched degree of ischemia–reperfusion acute kidney injury(Springer Nature, 2022-01-12) Soranno, Danielle E.; Baker, Peter, II.; Kirkbride-Romeo, Lara; Wennersten, Sara A.; Ding, Kathy; Keith, Brysen; Cavasin, Maria A.; Altmann, Christopher; Bagchi, Rushita A.; Haefner, Korey R.; Montford, John; Gist, Katja M.; Vergnes, Laurent; Reue, Karen; He, Zhibin; Elajaili, Hanan; Okamura, Kayo; Nozik, Eva; McKinsey, Timothy A.; Faubel, Sarah; Pediatrics, School of MedicineAcute kidney injury (AKI) is common in patients, causes systemic sequelae, and predisposes patients to long-term cardiovascular disease. To date, studies of the effects of AKI on cardiovascular outcomes have only been performed in male mice. We recently demonstrated that male mice developed diastolic dysfunction, hypertension and reduced cardiac ATP levels versus sham 1 year after AKI. The effects of female sex on long-term cardiac outcomes after AKI are unknown. Therefore, we examined the 1-year cardiorenal outcomes following a single episode of bilateral renal ischemia–reperfusion injury in female C57BL/6 mice using a model with similar severity of AKI and performed concomitantly to recently published male cohorts. To match the severity of AKI between male and female mice, females received 34 min of ischemia time compared to 25 min in males. Serial renal function, echocardiograms and blood pressure assessments were performed throughout the 1-year study. Renal histology, and cardiac and plasma metabolomics and mitochondrial function in the heart and kidney were evaluated at 1 year. Measured glomerular filtration rates (GFR) were similar between male and female mice throughout the 1-year study period. One year after AKI, female mice had preserved diastolic function, normal blood pressure, and preserved levels of cardiac ATP. Compared to males, females demonstrated pathway enrichment in arginine metabolism and amino acid related energy production in both the heart and plasma, and glutathione in the plasma. Cardiac mitochondrial respiration in Complex I of the electron transport chain demonstrated improved mitochondrial function in females compared to males, regardless of AKI or sham. This is the first study to examine the long-term cardiac effects of AKI on female mice and indicate that there are important sex-related cardiorenal differences. The role of female sex in cardiovascular outcomes after AKI merits further investigation.Item Matching Human Unilateral AKI, a Reverse Translational Approach to Investigate Kidney Recovery after Ischemia(American Society of Nephrology, 2019-06) Soranno, Danielle E.; Gil, Hyo-Wook; Kirkbride-Romeo, Lara; Altmann, Christopher; Montford, John R.; Yang, Haichun; Levine, Ani; Buchanan, Jane; Faubel, Sarah; Pediatrics, School of MedicineBackground: The duration of renal ischemia that is associated with (or leads to) renal injury in patients is uncertain, and a reverse translational research approach has been proposed to improve animal models of AKI to facilitate clinical translatability. We developed a two murine models of unilateral renal ischemia to match a recently published human study that investigated renal injury after unilateral renal ischemia during partial nephrectomy. Methods: Eight 10-week-old C57BL/6 male mice underwent left UiAKI or sham procedure, with or without intra-operative ice packs. Functional, histological, and biomarker outcomes were followed at 2, 6 and 24 hours, or 14 or 28 days later. The 14 and 28 day cohorts were duplicated such that contralateral nephrectomy could be performed 3 days prior to sacrifice with functional measurements obtained to isolate the glomerular filtration rate of the injured kidney. Results: The short-term outcomes correlated with the human study findings with urine and serum biomarkers of injury peaking around 24 hours and then normalizing, and reassuring immediate histological outcomes. Functional and histological outcomes at the later time-points (14 and 28 days) demonstrate an increase in fibrosis markers, and a reduction in glomerular filtration rate in the injured kidney, corresponding to the duration of ischemia, while serum and urine biomarkers remained reassuring. Conclusions: Our findings suggest that clinically available biomarkers of renal function are falsely reassuring against long-term injury following UiAKI, and that the duration of ischemia correlates with impaired function and increased fibrosis.Item Measurement of glomerular filtration rate reveals that subcapsular injection of shear‐thinning hyaluronic acid hydrogels does not impair kidney function in mice(Wiley, 2022-03) Soranno, Danielle E.; Kirkbride-Romeo, Lara; Han, Daniel; Altmann, Christopher; Rodell, Christopher B.; Pediatrics, School of MedicineThe continued development of minimally invasive therapeutic implants, such as injectable hydrogels, necessitates the concurrent advancement of methods to best assess their biocompatibility via functional outcomes in vivo. Biomaterial implants have been studied to treat kidney disease; however, assessment of biocompatibility has been limited to biomarker and histological assessments. Techniques now exist to measure kidney function serially in vivo in murine studies via transcutaneous measurements of glomerular filtration rate (tGFR). In this study, adult male and female wild-type BalbC mice underwent right unilateral nephrectomy. The remaining solitary left kidney was allowed 4 weeks to recover via compensatory hypertrophy, after which subcapsular injection of either saline or shear-thinning hyaluronic acid hydrogel was performed. Serial tGFR measurements before and after treatment were used to assess the effect of hydrogel injection on kidney filtration. Urine and serum biomarkers of kidney function, and kidney histology were also quantified. Hydrogel injection did not affect kidney function, as assessed by tGFR. Results were in agreement with standard metrics of serum and urine biomarkers of injury as well as histological assessment of inflammation. The model developed provides a direct functional assessment of implant compatibility for the treatment of kidney disease and impact on kidney function.Item Metabolomics assessment reveals oxidative stress and altered energy production in the heart after ischemic acute kidney injury in mice(Elsevier, 2019-03) Fox, Benjamin M.; Gil, Hyo-Wook; Kirkbride-Romeo, Lara; Bagchi, Rushita A.; Wennersten, Sara A.; Haefner, Korey R.; Skrypnyk, Nataliya I.; Brown, Carolyn N.; Soranno, Danielle E.; Gist, Katja M.; Griffin, Benjamin R.; Jovanovich, Anna; Reisz, Julie A.; Wither, Matthew J.; D'Alessandro, Angelo; Edelstein, Charles L.; Clendenen, Nathan; McKinsey, Timothy A.; Altmann, Christopher; Pediatrics, School of MedicineAcute kidney injury (AKI) is a systemic disease associated with widespread effects on distant organs, including the heart. Normal cardiac function is dependent on constant ATP generation, and the preferred method of energy production is via oxidative phosphorylation. Following direct ischemic cardiac injury, the cardiac metabolome is characterized by inadequate oxidative phosphorylation, increased oxidative stress, and increased alternate energy utilization. We assessed the impact of ischemic AKI on the metabolomics profile in the heart. Ischemic AKI was induced by 22 minutes of renal pedicle clamping, and 124 metabolites were measured in the heart at 4 hours, 24 hours, and 7 days post-procedure. 41% of measured metabolites were affected, with the most prominent changes observed 24 hours post-AKI. The post-AKI cardiac metabolome was characterized by amino acid depletion, increased oxidative stress, and evidence of alternative energy production, including a shift to anaerobic forms of energy production. These metabolomic effects were associated with significant cardiac ATP depletion and with echocardiographic evidence of diastolic dysfunction. In the kidney, metabolomics analysis revealed shifts suggestive of energy depletion and oxidative stress, which were reflected systemically in the plasma. This is the first study to examine the cardiac metabolome after AKI, and demonstrates that effects of ischemic AKI on the heart are akin to the effects of direct ischemic cardiac injury.Item Prolonged acute kidney injury exacerbates lung inflammation at 7 days post‐acute kidney injury(Wiley, 2014-07-22) Andres-Hernando, Ana; Altmann, Christopher; Bhargava, Rhea; Okamura, Kayo; Bacalja, Jasna; Hunter, Brandi; Ahuja, Nilesh; Soranno, Danielle; Faubel, Sarah; Pediatrics, School of MedicinePatients 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.