Kidney Injury Molecule-1 Research Articles

The effect of piezo-lithotripsy with 2-and 8-mm focus sizes on stone disintegration and renal injury.

To compare the efficacy and safety of shock-wave lithotripsy (SWL) using a narrow-focus and wide-focus for renal stones. A double-blind randomized trial included adult patients with solitary radio-opaque renal pelvic stone 1-2 cm. Patients were randomized into two groups; narrow-focus (2 mm) SWL and wide-focus (8mm) SWL. The stone-free rate (SFR) and presence of complications such as hematuria, fever, pain, and peri-renal hematoma were evaluated. Preoperative and postoperative urinary markers (NGAL and KIM-1) levels were compared to assess the renal injury. A total of 135 patients were recruited for this study. The SFR after the first SWL session was 79.2% and 69.1% in narrow- and wide-focus groups, respectively. There was a comparable rise in the median (IQR) 2-hour NGAL level in both groups (p= 0.62). However, the rise in the median (IQR) 2-hour KIM-1 level was significantly higher in the narrow-focus 4.9 (4.6, 5.8) ng/mL compared with the wide-focus group 4.4 (3.2, 5.7) ng/mL; (p=0.02). Nevertheless, 3-day urinary markers were significantly improved in NGAL and in KIM-1 (p= 0.263 and 0.963), respectively. The overall SFR after three sessions was 86.6% and 86.8% in narrow- and wide-focus groups, respectively (p=0.77). Both groups were comparable in complications, apart from the median (IQR) pain score and the percentage of high-grade hematuria which were significantly higher in the narrow-focus group (p<0.001and p=0.03), respectively. Narrow-focus and wide-focus SWL were associated with comparable outcomes and re-treatment rates. However, narrow-focus lithotripsy was associated with significantly higher morbidity in terms of pain and hematuria.

Predicting the incidence of chronic kidney disease in patients with myocardial infarction and acute kidney injury

Aim. To estimate the incidence of chronic kidney disease (CKD) and develop a calculator to estimate the CKD probability in patients with myocardial infarction (MI) and acute kidney injury (AKI).Material and methods. A total of 193 patients with MI aged 34-79 years were examined: 123 patients with MI and signs of AKI, 70 patients without AKI. In all patients, the levels of C-reactive protein, troponin I, N-terminal pro-brain natriuretic peptide (NT-proBNP), microalbuminuria (MA), creatinine, and glomerular filtration rate (GFR) were determined. In the presence of AKI criteria on the 3rd day and at discharge, the level of kidney injury molecule-1 (KIM-1) molecule and interleukin-18 was examined in the urine. Six months after discharge, GFR was assessed over time. Patients of both groups underwent coronary angiography with stenting of infarct-related artery.Results. The GFR at admission in patients with AKI was lower than in the group without AKI with normal creatinine levels. Following correlations between AKI and markers of cardiovascular events were revealed: KIM-1 and NT-proBNP (r=0,29 p=0,031), GFR and NT-proBNP (r=-0,22 p=0,015), NT-proBNP and IL-18 (r=0,18 p=0,045), MA with troponin I and CRP (r=0,20 p=0,048 and r=0,29 p=0,001). After six months, persistent renal function decline was more frequently diagnosed in patients with acute MI and AKI on index hospitalization. An equation for a multifactorial model for CKD risk was created: P(CKD)=exp(z)/(1+exp(z)), z=-1,113092e+01 — 4,082006e-02 * troponin I + 8,553826e-04 * NT-proBNP (discharge) + 1,620188e-01 * age + 3,411724e-02 * systolic blood pressure -7,753111e-03 * MA. ROC analysis revealed the most reliable sensitivity of 83% and specificity of 88,2% for the threshold value of CKD probability of 86,1%.Conclusion. Patients with MI and AKI have a significant risk of CKD within 6 months after ACS. The created mathematical model and calculator determine the likelihood of CKD.

Iohexol-Measured Glomerular Filtration Rate and Urinary Biomarker Changes between Vancomycin and Vancomycin Plus Piperacillin-Tazobactam in a Translational Rat Model.

Recent clinical studies have reported additive nephrotoxicity with the combination of vancomycin and piperacillin-tazobactam. However, preclinical models have failed to replicate this finding. This study assessed differences in iohexol-measured glomerular filtration rate (GFR) and urinary injury biomarkers among rats receiving this antibiotic combination. Male Sprague-Dawley rats received either intravenous vancomycin, intraperitoneal piperacillin-tazobactam, or both for 96 h. Iohexol-measured GFR was used to quantify real-time kidney function changes. Kidney injury was evaluated with the urinary biomarkers kidney injury molecule-1 (KIM-1), clusterin, and osteopontin. Compared to the control, rats that received vancomycin had numerically lower GFRs after drug dosing on day 3. Rats in this group also had elevations in urinary KIM-1 on experimental days 2 and 4. Increasing urinary KIM-1 was found to correlate with decreasing GFR on experimental days 1 and 3. Rats that received vancomycin plus piperacillin-tazobactam (vancomycin+piperacillin-tazobactam) did not exhibit worse kidney function or injury biomarkers than rats receiving vancomycin alone. The combination of vancomycin and piperacillin-tazobactam does not cause additive nephrotoxicity in a translational rat model. Future clinical studies investigating this antibiotic combination should employ more sensitive biomarkers of kidney function and injury, similar to those utilized in this study.

Evaluation of serum leptin and adiponectin and their associations with obesity-related renal injury among Egyptian adolescents

Background/aim Childhood obesity has come to be a worldwide epidemic. Current epidemiological data advocate that obesity is linked with an increased threat of renal injury in children. Early markers will be beneficial in the prevention of renal injury. The present study aimed to assess serum levels of leptin and adiponectin and their associations with comorbidities of obesity to examine their potential effects on obesity-related renal injury among Egyptian overweight/obese adolescents. In addition, the study aimed an analysis of the kidney injury molecule-1(KIM-1) to identify the early renal effect of obesity. Subjects and methods A case–control study was conducted on 45 Egyptian overweight/obese adolescents aged 10–18 years of both sexes and 44 age- and Sex-matched healthy individuals. Serum fasting glucose and insulin were analyzed, and a homeostasis model assessment of insulin resistance was calculated. Serum leptin, adiponectin, and KIM-1 were measured using ELISA techniques. Results The overweight/obese group had significantly higher KIM-1 and leptin levels, and lower adiponectin levels in comparison to the control group (P=&lt;0.05). Serum adiponectin levels had significant negative correlations, with both systolic (r=−0.480, P=0.013) and diastolic (r=−0.491, P=0.011) blood pressure, while serum leptin levels did not correlate with BMI, systolic blood pressure, diastolic blood pressure, HOMA- IR, eGFR, or KIM-1 in the study group (P&gt;0.05). Conclusion Leptin and adiponectin are the main pathogenic factors for renal injury in obese adolescents.

Effect and Mechanism of CircPTPN4 Expression in Carboxylated Single-Walled Carbon Nanotubes on Renal Fibrosis

This research was aimed to investigate the effect of circPTPN4 overexpression in carboxylated single-walled carbon nanotubes (SWCNT-COOH) on renal fibrosis (RF) in mice. SWCNT was oxidized to SWCNT-COOH by concentrated sulfuric acid and nitric acid (3:1, v/v). After characterization and analysis, the effect of SWCNT-COOH on erythrocyte status was detected. The RF mice (RFM) model was induced by SWCNT-COOH, normal mice as normal control (NC), and 1×108 TU/mL lenti-NC was injected into the tail vein as negative control, and 1×108 TU/mL lenti-circPTPN4 was injected for circPTPN4 overexpression. The expression of circPTPN4 was tested by qRT-PCR. Serum creatinine (Cr), blood urea nitrogen (BUN), interleukin 1β (IL-1β), IL-6, transforming growth factor β1 (TGF-β1), kidney injury molecule 1 (KIM-1), and neutrophil gelatinase-associated lipocalin (NGAL) were tested by ELISA. HE, Masson, and immunohistochemistry were used to detect the pathological changes of kidney tissue. The protein expressions of collagen I (COL1), fibronectin (Fn), α-SMA, TGF-β1, Smad3, p-Smad3, and Smad7 were tested by Western blot (WB). It presented SWCNT-COOH was successfully prepared by chemical oxidation method, with an average particle size of 98.1 nm and an average Zeta potential of −38.91 mV. SWCNT-COOH had good hydrophilicity, and did not cause aggregation and morphology changes of red blood cells. As against NC, the expression of circPTPN4 in RFM and lenti-NC groups was decreased; the kidney coefficient was increased, and the normal structure of the kidney was abnormal, accompanied by inflammatory cell infiltration and collagen microformation; serum Cr, BUN, IL-1β, IL-6, and TGF-β1 were increased, and KIM-1 and NGAL in renal cortex were decreased; the protein expressions of COL1, Fn, α-SMA, TGF-β1, and p-Smad3 in the kidney were increased, and the protein expression of Smad7 was decreased (P &lt;0.05). As against RFM, the expression of circPTPN4 in lenti-circPTPN4 group was increased; the kidney coefficient decreased and the kidney structure returned to normal; COL1, Fn, α-SMA, TGF-β1, and p-Smad3 in the kidney were decreased, and that of Smad7 was increased (P &lt;0.05). SWCNT-COOH has good blood compatibility characteristics and can induce RF in mice. The expression of circPTPN4 was down-regulated in the RFM. Overexpression of circPTPN4 can restore the normal renal function of RFM, inhibiting the inflammatory response and RF process.

Protective effect of citronellol in rhabdomyolysis-induced acute kidney injury in mice.

Acute kidney injury (AKI) is a serious pathophysiological event consequent to rhabdomyolysis. Inflammatory mechanisms play a role in the development of rhabdomyolysis-induced AKI. Citronellol (CT) is a naturally occurring monoterpene in essential oils of aromatic plant species. In this study, we explored the protective effects of citronellol on AKI resulting from glycerol-induced rhabdomyolysis. Rhabdomyolysis was induced by a single intramuscular injection of glycerol 50% (10mg/kg) in the thigh caudal muscle. Four groups of mice were assigned, including a control group, a group administered with glycerol to induce AKI as a model, a group treated with glycerol plus 50mg/kg CT, and a group treated with glycerol plus 100mg/kg CT. The renal function of mice from all groups was evaluated using kidney histopathological changes and kidney injury molecule-1 (KIM-1). Myoglobin levels were measured to detect rhabdomyolysis. Apoptosis was evaluated by renal cleaved caspase-3 and BAX levels. Both doses of citronellol (50mg/kg and 100mg/kg) significantly reduced KIM-1 mRNA expression and myoglobin levels compared to the glycerol group. In addition, citronellol resulted in lower cleaved caspase-3 and BAX in the renal tissue, indicating that citronellol exerted an anti-apoptotic effect in AKI. Citronellol showed a reno-protective effect against rhabdomyolysis-induced AKI, which may be attributed to its anti-apoptotic effects.

Notoginsenoside R_1 interferes with renal oxidative stress and Nrf2/HO-1 signaling pathway to alleviate kidney injury in mice with IgA nephropathy and its mechanism

The purpose of this study was to investigate the effect of notoginsenoside R_1(NGR_1) on alleviating kidney injury by regulating renal oxidative stress and the Nrf2/HO-1 signaling pathway in mice with IgA nephropathy(IgAN) and its mechanism. The mouse model of IgAN was established using a variety of techniques, including continuous bovine serum albumin(BSA) gavage, subcutaneous injections of carbon tetrachloride(CCl_4) castor oil, and tail vein injections of lipopolysaccharide(LPS). After successful modeling, mice with IgAN were randomly separated into a model group, low, medium, and high-dose NGR_1 groups, and a losartan group, and C57BL6 mice were utilized as normal controls. The model and normal groups were given phosphate buffered saline(PBS) by gavage, the NGR_1 groups were given varying dosages of NGR_1 by gavage, and the losartan group was given losartan by gavage for 4 weeks. The 24-hour urine of mice was collected after the last administration, and serum and kidney tissues of mice were taken at the end of the animal experiment. Then urine red blood cell count(URBCC), 24-hour urine protein(24 h protein), serum creatinine(Scr), and blood urea nitrogen(BUN) levels were measured. The enzyme-linked immunosorbent assay(ELISA) was used to detect the levels of galactose-deficient IgA1(Gd-IgA1), kidney injury molecule 1(Kim-1), and neutropil gelatinase-associated lipocalin(NGAL) in the mouse serum. The assay kits were used to detect the levels of malondialdehyde(MDA) and superoxide dismutase(SOD), and immunofluorescence(IF) was used to detect the expression level of glutathione peroxidase 4(GPX4) in the mesangial region. Western blot was used to detect the protein expression of nuclear transcription factor E2 related factor 2(Nrf2)/heme oxygenase 1(HO-1) signaling pathway in the renal tissue. Hematoxylin-eosin(HE) staining was used to observe pathological alterations in the glomerulus of mice. The results revealed that, as compared with the model group, the serum Gd-IgA1 level, URBCC, 24 h protein level, renal damage markers(Kim-1 and NGAL) in the high-dose NGR_1 group decreased obviously and renal function indicators(BUN, Scr) improved significantly. The activity of SOD activity and expression level of GPX4 increased significantly in the high-dose NGR_1 group, whereas the expression level of MDA reduced and protein expression levels of Nrf2 and HO-1 increased. Simultaneously, HE staining of the renal tissue indicated that glomerular damage was greatly decreased in the high-dose NGR_1 group. In conclusion, this study has clarified that NGR_1 may alleviate the kidney injury of mice with IgAN by activating the Nrf2/HO-1 signaling pathway, improving antioxidant capacity, and reducing the level of renal oxidative stress.

Value of Serum Kidney Injury Molecule-1 in Early Prediction of Kidney Injury in Patient with Ascites and Spontaneous Bacterial Peritonitis

Value of Serum Kidney Injury Molecule-1 in Early Prediction of Kidney Injury in Patient with Ascites and Spontaneous Bacterial Peritonitis

Новые биомаркеры повреждения почек и их использование при малоинвазивном лечении мочекаменной болезни.

Introduction. The effect of various minimally invasive treatment for kidney stones on renal function has not been sufficiently studied. To assess the specificity, severity, and prognostic significance of renal injury of urolithiasis and its minimally invasive treatment, it is necessary to search for «biomarkers of injury». The concentration of serum urea and creatinine used in routine clinical practice, the glomerular filtration rate change in the later stages of the disease and are functional parameters. Materials and methods. The data were searched in the PubMed, Web of Science, Google Scholar, еLibrary.ru using the following keywords: «acute kidney injury», «KIM-1», «kidney injury molecule 1», «NGAL», «neutrophil gelatinase- associated lipocalin», «L-FABP», «liver-type fatty acid binding protein», «cystatin C», «retrograde intrarenal surgery», «percutaneous nephrolithotomy», «kidney injury urolithiasis», «kidney injury nephrolithiasis». Results. Today new biomarkers have been proposed to detect renal injury at the initial stages. These are neutrophil gelatinase-associated lipocalin (NGAL), cystatin C, kidney injury molecule-1 (KIM-1) and liver-type fatty acid binding protein (L-FABP). The level of NGAL and KIM-1 increases until the serum creatinine level increases and the corresponding histological changes in the renal parenchyma develop. In percutaneous nephrolithotomy, multiple punctures and postoperative bleeding are independent risk factors for deterioration of renal function in the long term, and the large size and high density of stones, staghorn stones, and long duration of intervention are largely associated with the development of acute renal injury in the early postoperative period. Obstructive uropathy affects kidney damage in the postoperative period. The elimination of obstruction leads to a decrease in KIM-1 in urine already in the early postoperative period. The dynamics of biomarker levels suggests that percutaneous nephrolithotomy causes more renal injury than retrograde intrarenal surgery (RIRS). Conclusion. Аny minimally invasive treatment for kidney stones may lead to renal injury, which is not always accompanied by impaired function. The mechanisms of renal injury in various variants of minimally invasive treatment for kidney stones have specific features, and the short-term and long-term consequences are currently not fully determined. Further research evaluating the effect of various minimally invasive methods of urolithiasis treatment on the condition of the renal tubules using modern biomarkers is needed.

Identification of cell division cycle protein 20 in various forms of acute and chronic kidney injury in mice.

Tubular epithelial cell fate following exposure to various types of injurious stimuli can be decided at distinct cell cycle checkpoints. One such checkpoint occurs during mitosis, known as the spindle assembly checkpoint, and is tightly regulated through the actions of cell division cycle protein 20 (CDC20). Due to our paucity of knowledge about the role of CDC20 in the kidney, the present study was designed to investigate the expression levels and distribution of CDC20 within the kidney and how pharmacological inhibition of CDC20 function affects kidney recovery using various rodent models of kidney injury. CDC20 is normally detected in distal tubules, but upon injury by either cisplatin administration or ureter obstruction, CDC20 accumulation is considerably elevated. Blockade of CDC20 activity using a selective pharmacological inhibitor, Apcin, lowered serum creatinine, tubular damage, and DNA injury following acute kidney injury compared with vehicle-treated mice. In unilateral ureteral obstruction, Apcin reduced tissue kidney injury molecule-1 levels, sirius red staining, and tubulointerstitial α-smooth muscle actin staining in the tissue. The findings in the present study demonstrated that elevations in CDC20 levels in the kidney are associated with kidney injury and that inhibition of CDC20 can alleviate and reverse some of the pathological effects on the architecture and function of kidney.NEW & NOTEWORTHY To our knowledge, this is the first study to characterize the expression and localization of cell division cycle 20 protein (CDC20) in normal and acute, and chronically injured kidneys. Tubular epithelial cell damage was markedly reduced through the administration of a selective inhibitor of CDC20, Apcin. This study provides new evidence that CDC20 can be induced in damaged kidney cells and negatively impact the recovery of the kidney following acute kidney injury.

399-P: Dapagliflozin Is Protective in a Murine Model of Balkan Nephropathy

Episodes of acute kidney injury (AKI) increase the risk of chronic kidney disease (CKD). Proximal tubular uptake of aristolochic acid (AA) induces aristolactam (AL)-DNA adducts, which induce a p53-mediated DNA damage response and acute tubular injury. Recurrent exposure to AA causes kidney function loss and fibrosis in humans (Balkan nephropathy), and is a model of AKI to CKD transition. SGLT2 inhibitors protect against CKD progression regardless of the presence of diabetes, however, the underlying mechanism is still unclear. Here we elucidated the effects of SGLT2 inhibition on AA-induced kidney injury. 15-week-old C57BL/6J female and male mice were administered vehicle or AA every 3 days for 3 weeks at a dose of 10 and 3 mg/kg i.p., respectively. Application of dapagliflozin (dapa, 0.01 g/kg diet) or vehicle was initiated 7 days prior to AA injections. Urine/plasma were collected after completion of AA injections and 3 weeks later together with kidneys (n=7-11/group). AA-induced increases in plasma creatinine and urinary albumin excretion were robustly attenuated by dapa independent of sex. These effects of dapa were associated with lower urinary levels of kidney-injury molecule 1 (KIM1, normalized to creatinine) after injection and lower kidney mRNA expression of p53 and KIM1 at harvest. Renal up-regulation of pro-inflammatory and pro-fibrotic genes as well as collagen staining by AA were likewise significantly attenuated by dapa. Dapa caused a minor numerical reduction in kidney AL-DNA adduct formation when assessed one day after a single AA injection (by ~10%; P=0.084). In conclusion, dapa attenuated the AA-induced p53-mediated DNA damage response and subsequent nephropathy. SGLT2 inhibitors may protect the kidneys by improving the tubular response to nephrotoxins. Disclosure Y.Oe: None. Y.Kim: None. V.S.Sidorenko: None. S.Kanoo: None. N.Lopez: None. H.A.Goodluck: None. V.Vallon: Research Support; NIH - National Institutes of Health, Gilead Sciences, Inc., Merck Sharp &amp; Dohme Corp., Novo Nordisk, Maze Therapeutics, Boehringer-Ingelheim, Speaker's Bureau; AstraZeneca. Funding National Institutes of Health (R01DK112042, R01DK132690, R01AG061296, P30DK079337)

The effect of glycine on oxidative stress, inflammation and renin-angiotensin system in kidneys and aorta of cyclosporine-administered rats

Cyclosporine A (CsA) is an immunosuppressive drug, used in organ transplantations. Oxidative stress, inflammation and renin-angiotensin system (RAS) activation play an important role in CsA-toxicity. Glycine (Gly) has antioxidant and anti-inflammatory effects. In this study, Gly was investigated for its protective role against CsA-induced toxicity. CsA (20 mg/kg/day; subcutaneously) was administered to rats along with Gly injection (250 or 1000 mg/kg; intraperitoneally) for 21 days. Renal function markers [serum urea and creatinine and urinary protein and kidney injury molecule levels and creatinine clearance values] together with histopathological examinations were performed. Oxidative stress (reactive oxygen species, thiobarbutiric acid reactive substances, advanced oxidation products of protein, glutathione, ferric reducing anti-oxidant power and 4-hydroxynonenal levels), and inflammation (myeloperoxidase activity) were determined in kidney tissue. The RAS system [angiotensin II (Ang II) levels, and mRNA expressions of angiotensin converting enzyme (ACE), angiotensin II type-I receptor (AT1R)] and NADPH-oxidase 4 (NOX4) were measured in kidney and aorta. CsA caused significant disturbances in renal function markers, increases in oxidative stress and inflammation parameters and renal damage. Serum angiotensin II levels and mRNA expressions of ACE, AT1R and NOX4 elevated in the aorta and kidney of CsA-rats. Gly, especially its high-dose, alleviated renal function markers, oxidative stress, inflammation and renal damage in CsA-rats. Moreover, serum Ang II levels and mRNA expressions of ACE, AT1R and NOX4 decreased significantly in aorta and kidney in CsA-rats due to Gly treatment. Our results indicate that Gly may be useful for the prevention of CsA-induced renal and vascular toxicity.

#5436 CHARACTERIZATION OF KIDNEY FUNCTIONAL DAMAGE ASSOCIATED TO CO-TREATMENT WITH IMMUNE CHECKPOINT INHIBITORS AND CISPLATIN

Abstract Background and Aims Advances in the knowledge of the immune response against tumors and the evasion mechanisms of these have led to develop new cancer therapies focused on improving the immune response and thus increasing patient survival. This is the case of immunotherapeutic treatment based on immune checkpoint inhibitors (ICI). However, treatment based on these antibodies is associated with autoimmune side effects, in most of the body organs, that limit their use. Although nephrotoxicity is rare, renal effects have been shown to worsen the prognosis of cancer patients. Recently, therapies based on the combination of immuno and chemotherapy have been approved. They have improved efficacy but have increased the risk of suffering nephrotoxic adverse effects. Our hypothesis is that kidney damage associated with ICIs could be subclinical and not evidenced by the parameters used in clinical practice (mainly plasma creatinine). The aim of this work was to characterize functional kidney damage associated with ICI (anti-CTLA-4) in combination with chemotherapy (cisplatin) in a murine model. Method C57BL/6 mice were treated with combined therapy of cisplatin (10 mg/kg, single dose) and anti-CTLA-4 (10 or 15 mg/kg/day, for 6 days) administrated by intraperitoneal injection. In addition, groups treated with drug monotherapies and a control group were included. Urine and blood samples were collected at baseline, on day 3 and on day 6 (sacrifice). Biomarkers of subclinical kidney damage were determined by ELISA in urine samples. There were albumin, neutrophil gelatinase-associated lipocalin (NGAL) and kidney injury molecule 1 (KIM-1). Blood samples were centrifuged to obtain plasma, in which creatinine and urea were measured using colorimetric techniques. Data were analyzed with the statistical software SPSS®. Results Plasma creatinine and urea were elevated in the combined therapy groups with respect to the monotherapies. However, these parameters were similar to the normal range, so they do not reflect obvious kidney injury. It was evidenced a statistically significant elevation of biomarkers of subclinical kidney damage in the combined therapy groups with respect to monotherapies and control group. Conclusion This study suggests that the combination of anti-CTLA-4 with cisplatin could cause a potenciation effect on subclinical kidney damage compared to monotherapies. This experimental model would make possible to study the nephrotoxicity mechanisms of ICI. Moreover, it could have a potential diagnostic utility through the identification of biomarkers of subclinical kidney damage, that would avoid biopsy.

#6546 RENAL TUBULAR TOXICITY OF ORGANOPHOSPHATE FLAME RETARDANTS IN PATIENTS WITH CHRONIC KIDNEY DISEASE

Abstract Background and Aims Organophosphate flame retardants (OPFRs) are widely utilized flame retardants and considered less harmful than legacy brominated flame retardants. However, owing to their widespread utilization, OPFRs have led to extensive and persistent human exposure, with potentially hazardous effects on human health such as nephrotoxicity. Experimental and clinical studies have revealed that OPFR exposure is associated with renal tubular toxicity and renal impairment. However, the nephrotoxic mechanisms of OPFRs have not yet been clarified, and their impact on renal tubular injury has less been evaluated in patients with chronic kidney disease (CKD). In this cross-sectional observational study, we assessed the urinary OPFR concentrations in CKD patients to evaluate the associations between OPFR exposure and renal tubular injury in this population. Method Adult CKD patients in Taiwan (≥ 20 years of age and with non-dialysis-dependent CKD stage 3–5) were recruited from the Kaohsiung Chang Gung Memorial Hospital between January 2020 and May 2021. The first-void urine samples in the morning were collected to measure the concentrations of 10 common OPFR compounds using an ultra-performance liquid chromatography-tandem mass spectrometry (Waters, Milford, MA, USA). The urinary novel renal biomarkers were also measured using enzyme-linked immunosorbent assays (kidney injury molecule-1 [KIM1] and 8-hydroxy-2-deoxyguanosine [8-OHdG]; Abcam, Trumpington, Cambridge, UK). OPFRs with concentrations below a limit of quantitation (LOQ) were considered undetectable, and LOQ/√2 was assigned to the non-detected samples for analysis. The associations between urinary renal biomarkers and ΣOPFR concentrations (i.e., the sum of 10 OPFR compounds) were assessed via Spearman's correlation analysis. Simple linear regression analyses were conducted to evaluate the correlations between urinary renal biomarkers, ΣOPFR concentrations, and baseline patient characteristics. The effects of OPFR exposure on the urinary concentrations of KIM-1 and 8-OHdG in the enrolled CKD patients were examined in multiple linear regression analyses, adjusting for age, sex, body mass index, diabetes, hypertension, renal function, proteinuria, and covariates with a p-value &amp;lt; 0.1 in univariate analyses via the enter method. Results In this study, 163 CKD patients were enrolled for analysis (stage 3: n = 79 [49.47%]; stage 4: n = 48 [29.45%]; stage 5: n = 36 [22.08%]). The overall detection frequency of urinary OPFRs was 98.77% in the study cohort, with a median ΣOPFR of 2.04 μg/g Cr (interquartile range [IQR], 0.84–4.27). The median urinary KIM-1 and 8-OHdG concentrations were 185.89 ng/g Cr (IQR, 83.05–441.60) and 71.23 μg/g Cr (IQR, 37.87–149.73), respectively. In our analysis, urinary ΣOPFR concentrations were positively correlated with urinary KIM-1 and 8-OHdG concentrations (rs = 0.267 for KIM-1, p = 0.001; rs = 0.281 for 8-OHdG, p &amp;lt; 0.001) (Figure 1). In the multiple linear regression analyses, urinary ΣOPFR concentration was identified as an independent predictor positively associated with urinary renal biomarkers in the enrolled patients, with a 0.260 log ng/g Cr (95% confidence interval [CI], 0.140–0.380, p &amp;lt; 0.001) increase in urinary KIM1 and a 0.227 log μg/g Cr elevation (95% CI, 0.124–0.330, p &amp;lt; 0.001) in urinary 8-OHdG by per log μg/g Cr ΣOPFR (Figure 2). Conclusion OPFR exposure is common and associated with renal tubular injury as well as increased oxidative stress in CKD patients, which highlights its nephrotoxic potential in this vulnerable population.

#5826 NEPHROPROTECTIVE EFFECTS OF SEMAGLUTIDE IN A MOUSE MODEL OF HYPERTENSION-ACCELERATED DIABETIC KIDNEY DISEASE

Abstract Background and Aims Obesity, hyperglycemia and hypertension are critical risk factors for development of diabetic kidney disease (DKD). Emerging evidence suggests that glucagon-like peptide-1 receptor (GLP-1R) agonists improve cardiovascular and renal outcomes in type 2 diabetes patients. Here, we characterized the effect of long-acting GLP-1R agonist semaglutide alone and in combination with an ACE inhibitor in a model of hypertension-accelerated, advanced DKD facilitated by adeno-associated virus-mediated renin overexpression (ReninAAV) in uninephrectomized (UNx) female db/db mice. Method Seven weeks after ReninAAV administration and six weeks post-UNx, db/db UNx-ReninAAV mice were administered (q.d.) vehicle, semaglutide (30 nmol/kg, s.c.) or semaglutide (30 nmol/kg, s.c.) + lisinopril (30 mg/kg, p.o.) for 11 weeks. Endpoints included tail-cuff blood pressure evaluation at week 1 and 10, plasma/urine biochemistry, kidney histopathology as well as RNA sequencing. Results Semaglutide robustly reduced hyperglycemia, hypertension and albuminuria concurrent with notable improvements in glomerulosclerosis severity, urine/renal kidney injury molecule-1 (KIM-1) levels. Furthermore, semaglutide suppressed gene expression markers of extracellular matrix modelling and immune system activation. Co-administration of lisinopril further ameliorated hypertension, glomerulosclerosis as well as markers of fibrogenesis and inflammation. Conclusion Semaglutide improves disease hallmarks in the db/db UNx-ReninAAV mouse model of advanced DKD. Renal outcomes were further improved by combined antihypertensive standard-of-care. These data display the translatability of the db/db UNx-ReninAAV mouse model of DKD.

#4479 KIM-1, IL-18 AND NGAL IN MACHINE LEARNING PREDICTION OF KIDNEY INJURY AMONG CHILDREN UNDERGOING HEMATOPOIETIC STEM CELL TRANSPLANTATION

Abstract Background and Aims Children undergoing allogeneic hematopoietic stem cell transplantation (alloHSCT) are particularly vulnerable to acute kidney injury (AKI), especially in the early post-transplantation period. The major risk factors of AKI development are aggressive immunosuppression and infectious complications. In the meantime, malnutrition and hypermetabolic state of the patient, together with the routine intensive hydration during first 3 weeks after HSCT and subsequent forced diuresis, alter the serum creatinine concentration, modifying the estimated glomerular filtration rate (eGFR) value too. Therefore, the risk of underrating serum creatinine and overrating eGFR values is high, making the assessment of the degree of kidney damage during the first month after HSCT a challenge. Therefore, markers of tubular dysfunction and damage, like kidney injury molecule (KIM)-1, neutrophil gelatinase-associated lipocalin (NGAL) or interleukin (IL)-18, may be of added value while assessing renal function and analyzing the risk of AKI in this population. The aim of study was to assess the serum concentrations of damage biomarkers (KIM-1, NGAL, IL-18) in children undergoing alloHSCT, in relation to another surrogate marker of renal dysfunction, hyperfiltration. Another aim was to analyze the potential value of KIM-1, NGAL, and IL-18 as predictors of kidney damage in children after alloHSCT, with the use of artificial intelligence tools. Method The study group contained 22 children undergoing alloHSCT, followed up for 4 weeks after transplantation. Serum concentrations of KIM-1, NGAL, and IL-18 were assessed by ELISA in fixed time points (before HSCT, 1 day after HSCT, 1, 2 3, 4 weeks after transplantation). eGFR values (counted based on Schwartz formula) and the rate of hyperfiltration (eGFR &amp;gt; 140ml/min/1.73sq.m.) were evaluated at the beginning (before HSCT) and at the end (4 weeks after HSCT) of observation, when neither hydration nor diuretics were used. Statistical analysis was performed with the use of package Statistica, the comparisons between paired data were evaluated by using nonparametric tests (Friedman, Wilcoxon). Additionally, the patients within the database were randomly divided into two groups. The training group allowed to build a Random Forest Classifier (RFC) with the highest possible predictive power, while the testing group allowed to assess the effectiveness of prediction on new data and the clinical utility. Moreover, the contribution of individual variables was evaluated by GINI importance. Results KIM-1, NGAL, and IL-18 serum concentrations increased systematically until the 3rd week after HSCT, with statistically significant differences between subsequent observation points, then remained elevated until the 4th week after HSCT. Median eGFR values before transplantation and 4 weeks after HSCT were comparable, although the rate of patients with hyperfiltration increased. The RFC model built on the basis of 3 input variables, KIM-1, NGAL, and IL-18 concentrations in serum of children before HSCT, was able to effectively assess the rate of patients with hyperfiltration 4 weeks after the procedure. RF Classifier achieved AUROC of 0.8333, accuracy of 80.00%, positive predictive value of 0.8667, and sensitivity of 0.8000. The contribution of KIM-1, IL-18 and NGAL to the prediction in this model was comparable (33.73%, 32.77%, and 33.5%, respectively). Conclusion KIM-1, NGAL, and IL-18 are useful in assessing acute tubular damage in children after HSCT. Their values before HSCT may also serve as markers of incipient renal dysfunction 4 weeks after alloHSCT. The developed model seems a clinically useful tool to target patients who are at risk of kidney injury after HSCT. The Random Forest Classifier seems a promising tool for such analysis, that should be tested on a larger group of patients.

Dihydromyricetin attenuates cisplatin-induced acute kidney injury by reducing oxidative stress, inflammation and ferroptosis

BackgroundCisplatin is effective against various types of cancers. However, its clinical application is limited owing to its adverse effects, especially acute kidney injury (AKI). Dihydromyricetin (DHM), a flavonoid derived from Ampelopsis grossedentata, has varied pharmacological activities. This research aimed to determine the molecular mechanism for cisplatin-induced AKI. MethodsA murine model of cisplatin-induced AKI (22 mg/kg, I.P.) and a HK-2 cell model of cisplatin-induced damage (30 μM) were established to evaluate the protective function of DHM. Renal dysfunction markers, renal morphology and potential signaling pathways were investigated. ResultsDHM decreased the levels of renal function biomarkers (blood urea nitrogen and serum creatinine), mitigated renal morphological damage, and downregulated the protein levels of kidney injury molecule-1 and neutrophil gelatinase-associated lipocalin. It upregulated the expression levels of antioxidant enzymes (superoxide dismutase and catalase expression), nuclear factor-erythroid-2-related factor 2 (Nrf2) and its downstream proteins, including heme oxygenase-1 (HO-1), glutamate-cysteine ligase catalytic (GCLC) and modulatory (GCLM) subunits, thus eventually reducing cisplatin-induced reactive oxygen species (ROS) production. Moreover, DHM partially inhibited the phosphorylation of the active fragments of caspase-8 and -3 and mitogen-activated protein kinase and restored glutathione peroxidase 4 expression, which attenuated renal apoptosis and ferroptosis in cisplatin-treated animals. DHM also mitigated the activation of NLRP3 inflammasome and nuclear factor (NF)-κB, attenuating the inflammatory response. In addition, it reduced cisplatin-induced HK-2 cell apoptosis and ROS production, both of which were blocked by the Nrf2 inhibitor ML385. ConclusionsDHM suppressed cisplatin-induced oxidative stress, inflammation and ferroptosis probably through regulating of Nrf2/HO-1, MAPK and NF-κB signaling pathways.

Geldanamycin ameliorates multiple organ dysfunction and microthrombosis in septic mice by inhibiting the formation of the neutrophil extracellular network by activating heat shock factor 1 HSF1.

Sepsis and septic shock are common critical illnesses in the intensive care unit with a high mortality rate. Geldanamycin (GA) has a broad spectrum of antibacterial and antiviral activity and has inhibitory effects on various viruses. However, whether GA affects sepsis due to infections remains unknown. In this study, alanine aminotransferase, aspartate aminotransferase, blood urea nitrogen and creatinine in serum; neutrophil gelatinase-associated lipocalin and kidney injury molecule-1 in the urine, cytokines (tumour necrosis factor alpha, interleukin-1β and interleukin-6) in the bronchoalveolar lavage fluid and myeloperoxidase in the lung tissues were measured using enzyme-linked immunosorbent assay kits. Pathological injury was measured by hematoxylin and eosin staining and neutrophils were measured by flow cytometry analysis; related expressions were analysed by qPCR, western blot and immunofluorescence assay. The results showed that GA significantly ameliorated cecum ligation and puncture (CLP)-triggered liver, kidney and lung injury in septic mice. In addition, we found that GA dose-dependently inhibited microthrombosis and alleviated coagulopathy in septic mice. Further molecular mechanism analysis suggests that GA may act through upregulation of heat shock factor 1 and tissue-type plasminogen activator. In conclusion, our study elucidated the protective effects of GA in a mouse model established using CLP, and the results reveal that GA may be a promising agent for sepsis.

Mitochondrial DNA Changes in Blood and Urine Display a Specific Signature in Relation to Inflammation in Normoalbuminuric Diabetic Kidney Disease in Type 2 Diabetes Mellitus Patients.

Mitochondrial dysfunction is an important mechanism contributing to the development and progression of diabetic kidney disease (DKD). Mitochondrial DNA (mtDNA) levels in blood and urine were evaluated in relation to podocyte injury and proximal tubule (PT) dysfunction, as well as to a specific inflammatory response in normoalbuminuric DKD. A total of 150 type 2 diabetes mellitus (DM) patients (52 normoalbuminuric, 48 microalbuminuric, and 50 macroalbuminuric ones, respectively) and 30 healthy controls were assessed concerning the urinary albumin/creatinine ratio (UACR), biomarkers of podocyte damage (synaptopodin and podocalyxin), PT dysfunction (kidney injury molecule-1 (KIM-1) and N-acetyl-β-(D)-glucosaminidase (NAG)), and inflammation (serum and urinary interleukins (IL-17A, IL-18, and IL-10)). MtDNA-CN and nuclear DNA (nDNA) were quantified in peripheral blood and urine via qRT-PCR. MtDNA-CN was defined as the ratio of the number of mtDNA/nDNA copies via analysis of the CYTB/B2M and ND2/B2M ratio. Multivariable regression analysis provided models in which serum mtDNA directly correlated with IL-10 and indirectly correlated with UACR, IL-17A, and KIM-1 (R2 = 0.626; p < 0.0001). Urinary mtDNA directly correlated with UACR, podocalyxin, IL-18, and NAG, and negatively correlated with eGFR and IL-10 (R2 = 0.631; p < 0.0001). Mitochondrial DNA changes in serum and urine display a specific signature in relation to inflammation both at the podocyte and tubular levels in normoalbuminuric type 2 DM patients.

Urinary Kidney Injury Biomarkers Are Associated with Ischemia-Reperfusion Injury Severity in Kidney Allograft Recipients.

We explored the potential of emerging and conventional urinary kidney injury biomarkers in recipients of living donor (LD) or donation after circulatory death (DCD) kidney transplantation, patients with chronic kidney disease (CKD), and individuals from the general population. Urine samples from kidney allograft recipients with mild (LD; n = 199) or severe (DCD; n = 71) ischemia-reperfusion injury (IRI) were analyzed for neutrophil gelatinase-associated lipocalin (NGAL), insulin-like growth factor-binding protein 7 (IGFBP7), tissue inhibitor of metalloproteinases 2 (TIMP2), kidney injury molecule-1 (KIM-1), chemokine C-X-C motif (CXCL9), solute carrier family 22 member 2 (SLC22A2), nephrin, and uromodulin (UMOD) by quantitative multiplex LC-MS/MS analysis. The fold-change in biomarker levels was determined in mild and severe IRI and in patients with CKD stage 1-2 (n = 127) or stage ≥3 (n = 132) in comparison to the general population (n = 1438). Relationships between the biomarkers and total protein, β2-microglobulin (B2M), creatinine, and osmolality were assessed. NGAL, IGFBP7, TIMP2, KIM-1, CXCL9, and UMOD were quantifiable, whereas nephrin and SLC22A2 were below the limit of detection. Kidney injury biomarkers were increased up to 6.2-fold in allograft recipients with mild IRI and 8.3-fold in recipients with severe IRI, compared to the reference population, with the strongest response observed for NGAL and B2M. In CKD stage 1-2, B2M, NGAL, IGFBP7, TIMP2, KIM-1, UMOD, and CXCL9 were not altered, but in individuals with CKD stage ≥3, B2M, NGAL, and KIM-1 were increased up to 1.3-fold. IGFBP7, TIMP2, NGAL, and CXCL9 were strongly correlated (all r ≥ 0.8); correlations with B2M and TP were smaller (all r ≤ 0.6). IRI, but not stable CKD, was associated with increased urinary levels of kidney injury biomarkers determined by LC-MS/MS. Absolute and multiplexed protein quantitation by LC-MS/MS is an effective strategy for biomarker panel evaluation for translation toward the clinical laboratory.